Ketosis and Athletic Performance: More Than Fat Loss

The above video is a presentation by Peter Attia, M.D.

His talk is somewhat technical, but I always write blog posts hoping 20,000 people will *love* them, not that 1,000,000 will *like* them.

In this presentation, you will learn (in my words, not Pete’s):

– More about nutrition than most MDs learn in med school.

– How ketosis-adapted performance can aid fat loss and high-altitude resilience.

– Why the calorie estimates on treadmills and stationary bikes are complete BS.

– The three primary systems of energy production and basic organic chemistry, both of which aid understanding of all athletics.

Even if you struggle a little with vocabulary, the first 30 minutes are well worth watching a few times.

This talk made me immediately want to jump back on the Cyclical (or “Cyclic”) Ketogenic Diet (CKD), which was conceptually introduced to me in 1996-1998 by the writing of Lyle McDonald, Dr. Mauro Di Pasquale, and the late Dan Duchaine. It’s incredible for simultaneous fat loss and lean muscle gain, though perhaps needlessly complicated for non-athletes.

I usually limited the carb-reloading period to 12-18 hours after a glycogen depletion workout on Saturdays, though I experimented with moderate Wed night carb-ups while training for sports like kickboxing.

If you’ve experimented with ketosis, what was your approach and experience? Pros and cons?

For additional reading, I suggest the following posts by Dr. Attia:


Odds and Ends:

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219 Replies to “Ketosis and Athletic Performance: More Than Fat Loss”

  1. I did Kiefer’s Carb Nite protocol for six months last year. I’m 50 lbs overweight, and have been Crossfitting for almost three years. Down 50 lbs from pre-Crossfit days and figured I’d try Carb Nite after seeing Mark Bell’s results from 2012. The problem with ketogenesis and Crossfit is maintaining energy levels that support metcon performance. Some days in the gym were fine, but others were horrible in terms of strength and energy. If I do Carb Nite again I’ll take six months off from metcons and take on more of a strength-only focus. I lost 20 lbs on Carb Nite but once I returned to eating carbs regularly 10 lbs came right back. No big deal though…so did my performance in the gym. Might try carb nite with two refeeds during the week (exclusively rice & sweet potatoes) to maintain glycogen levels.

    1. I find 2 carb nites a week work the best. Especially when doing crossfit style workouts. Usually my carb nites are rice dishes. I love rice.

      1. I’m currently also following CarbNite, currently at 9% BF at 210lb, 6′. It’s a solid program, and hits the reward/sacrifice schedule with the yummy carb re-feeds. I keep the ULC days paleo, and the carb re-feeds GF. Lift 5 days a week (shockwave) 2 days of HIIT post re-feed, working great! feel awesome

      1. To put my comment in context, I only know Kiefer through his direct work with the Supertraining Gym team and athletes like Mark Bell. He and I have spoken in person a few times, and his results with powerlifters have been impressive. I am not very familiar with his writing.

      2. Perhaps, but he has been exposed multiple times for citation abusing – nicotine, creatine, the running article I mentioned, etc etc.

        It’s systematic and a gross appeal to “look at all my citations.”

      3. Kiefer has a background in physics not physiology. This much is obvious from the free chapters of CarbNite available on his site.

        At PaleoFX he actually claimed that women metabolize carbs differently than men and shouldn’t even have them after a workout. Oh and don’t run bitches cuz it will give you a flat ass. Hardcore Dangerous Kiefer 🙂

      4. Tim Sol has an excellent guide at all things supplements, check it out at www. examine DOT COM.

        He knows his stuff.

      5. Yeah Sol is correct. I wouldn’t follow Kiefer if you want to understand true physiology and not hype/citation abuse/misuse.

    2. I’ve heard going back to full carbs gradually can stop the post keto weight gain.

      Haven’t personally tried it yet as I still tolerate carbs well.

  2. I’ve messed with extremely low carb all week, refeed post workout saturday, 11am until 8pm-ish. Ive also tried adding a carb night on wed (100g of carbs for dinner). Havent had great success with either. My goal is to always be under 7-8% BF.

    I do a lot of olympic lifting and hypertrophy after, 5 days a week. All of my carbs come from, white rice, sweet potatoes, a little fruit (berries).

    So my question is, what am I doing wrong?

    Thanks Tim

    1. You have tried for 1 week, and you ask what you are doing wrong? Give it a go for a longer period a month or two. White rice, You don’t know about insulin, or Tim’s and most people in general trying to drop weight. Don’t eat anything (carbs) that are white. I don’t know you, but you say you do Olympic lifting followed by Hypertrophy ( training I assume ). After Olympic lifting then training to build muscle after (same day?). That is Ridiculous. There is not enough time (are you in a ketogenic state/ 1 week), and the amount of information you give, nobody could tell you what you’re doing wrong…. Just to kindly point that out.

  3. I tend to aim for a protein filled dinner and intermittent fast until 2pm next day, which is sufficient to reach a state of ketosis (as checked by ketostix). Coupled with a work out c. 12 hours post last meal, it really kicks off ketones in the body! Have been using this technique for fat loss post a heavy weekend of eating/ drinking, but clearly not daily. 1-2 days of that shows strong results on fat stores for me.

  4. I am in ketosis now!!! I go between a 4hr body and a strict Keto diet depending on my mood and how bored I get with the keto. The one thing that makes it easy to keep going is using ketostix to see if I am in ketosis, that and losing weight of course. I am less likely to break my diet or even come close to cheating if I am in a dark maroon zone of the stix and when I am not I tend to diet harder to get there. I have lost 27lbs in three months and that is with 8 days of hardcore cheating in Hawaii where i put back on 7lbs that I had lost. They came off pretty fast when I got back into the swing of things of course. I am shooting for another 20-30lbs. Thank you for your book, you put me on the right path.

  5. I’ve done Keto for the last four months. I love it. Went from 198 lbs to 178 lbs and feel like I’ve added a little muscle doing a lot of compound movement weight lifting.

    I’ve followed a simple Keto diet most of the time, keeping carbs to 5%, protein 20%, and fats around 70%. Tried a cyclical keto for a few weekends but wasn’t disciplined enough not to have fats with carbs.

    I started reading Peter Attia’s website,, a month ago. The guy is like Keto Superman. So much great information from a very reputable source, not only with medical knowledge, but athletic application data.

    Definitely recommend following a Keto diet if looking to drop fat.

  6. After watching Dr. Attia’s TED Med talk and checking out his website, I tweaked my Paleo diet to incorporate some dairy. It hasn’t hurt my fat loss and has given me more options. I enjoy ketosis; I have a clearer head, more energy, less food cravings, and I am losing a couple of pounds a week without any real training.

  7. Hi Tim,

    I first experimented with ketosis after reading 4HB nearly one year ago. I lost about 8,5 kg in 8 weeks but I probably gained 2 kg of muscle in that time too. I still live on the slow carb diet since then with influences of John Romaniello´s advices of intermittent fasting and Dave Asprey´s Bulletproof Coffee which is my breakfast. I am feeling very well and I am on track to reach my phsyical goals. I recommended the slow carb diet to a colleague of mine who lost 10 kg of fat in 5 weeks – she loves me now 😉 – thanks to you! The only con of being ketonic – bad breath. But if you know it you can work against it.

    Thx and all the best!

    1. What works very very well against bad breath is spirulina. Most of the standard supplements are rather expensive for the doses you’ll need but I’ve found one organic webshop in the Netherlands that sells a years supply for the price of one-two month with Now Foods and similar brands. It really works magic plus has several other positive side effects.

      1. Hi Floris,

        thx for the tip. It is a 4 hours drive from where I live to the netherlands so it shouldn´t be a problem to organise some of it. What is the name or URL of the webshop?

  8. I prefer to be in ketosis most of the time. I prefer it because I have more consistent energy and don’t feel as hungry as often. Also, as long as I’m eating grass fed meat, pastured eggs, organic bacon, ect. I find that I can eat like a fatty and stay at around 12% bodyfat, andI don’t just have a “fast metabolism”, i use to weight 300lbs. Only con for me is that I have to piss every hour while in ketosis.

  9. I have found using blood ketone monitors are a much more accurate way of measuring ketones than urine sticks, very easy to do too!

    An interesting read is ‘The Art & Science of Low Carb’ Performance’

    Dave Asprey also has really interesting views on exercise & ketosis in this video interview here

    Awesome topic!!! And thanks for sharing Tim… Guy

    1. The Dave Asprey link is a great resource filled with lots of useful bits of information. Just listened to the whole interview while on my morning run and was inspired.

      Thanks for this

  10. I’ve tried no-cabohydrate before and just felt really horrible, I.e. massive headaches, complete exhaustion, hunger, depression, haziness. I’m considering increasing portion sizes and waiting it out, to see if it improves but generally I’m actually kinda confused about diet these days. Everyone has their own idea about what’s right and the data is often misleading.

    Right now I’m on the slow carb diet but adding in some sweet potato, I’ve been losing weight, but put on a bit too much weight on cheat day that doesn’t go away fast enough. I have made progress, on my 2nd month, gonna go for another 30 days, maybe cut out the sweet potato, maybe include come no-carb meals but generally been finding the whole dieting thing confusing and frustrating. I find I get extremely hungry and kind exhausted and sick at night also.

    I’m sure people here will be pro SCD generally but any advice on how to clear up the fog and confusion on diet (could just be my own brain-fog) would be greatly appreciated, thanks.

    1. Alex, I have tried and failed at low carb diets several times and I think I’ve figured out how to make them manageable. I first tried slow carb and paleo with dismal results. It wasn’t that they were too strict. On the contrary: They weren’t strict enough. Also I just found out I am hypothyroid, so beans are some of the worst foods I can eat. Had no idea…

      Apart from not feeling well if you are experiencing fat loss, I’d continue to tweak the diet. Tim lists the common mistakes people make in the 4HB. I was frustrated when it wasn’t working for me, but as it turns out it was the beans. The number 1 mistake with low carb diets is not eating enough. Another is exercising too much. Not drinking enough water. Eat very generous portions. Someone I just had dinner with looked at me like I was committing slow suicide when I had 2 bun-less Double Doubles (no cheese) from In-N-Out burger for dinner tonight. Sure enough the ketostix say I have a “moderate” amount of ketones in my system, which is great compared to none, which is what I had a few days ago. In particular, eat more fat. It will help with energy and satiety. It has for me. Good luck.

      1. Best keto meal is a 4×4 from in n out, protein style and mustard-fried. 56g fat 60g protein and only 3g carbs.

  11. Mostly utter nonsense;

    1. N=1 experiments mean NOTHING.

    2. NUSi has more inherent bias than any medical journal ever could.

    3. There is no difference in fat loss between low carb keto and low carb non-keto diets.

    4. Lyle would go bugsh*t if he found his name alongside Kiefers. And would probably lose his sh*t if he knew how much his work has been bastardized here.

    5. 5 words: Metabolic ward studies – see them.

    1. I’m not claiming Lyle’s work is reflected in anything in this post. I’m trying to give credit where credit is due for piquing my interested in ketogenic diets, generally speaking.

    2. You need to go to Attia’s blog and read it. I paid the $50.00 for Lyles book and it’s amazing but Attia takes it to a new level – and so he should it’s ten years plus after Lyle’s publication.

    3. Who cares if “Lyle would lose his shit” or not. Let him do that and spread his childish, arrogant antics on even more message boards, so more people can be exposed to his questionable character.

      In fact, why don’t you direct him to this blog post, I’m sure it would rile him up good.

      Thanks for posting the video Tim, I’ll brew a pot of Maté and watch it before bed 😉

  12. Ive been on a 60 day test of MCT oil supplementation. I stopped all coconut oil intake. Resumed animal fat [butter intake]. I de-loaded my training for the period, did only 5 metcons, no lifting, but than maintained my normal regimen of surfing. I 90% paleo , and tried not create a fair base line, and try to get my body into ketosis. Very low carb intake which I actually bummed up especially prior of Intermittent Fasting. Been feeling over trained so Ive been using carbs to promote a food coma and get to sleep. Its helped. Were talking a small portion of white rice or corn flakes. I followed Nate Miyakis recommended approach here

    5 days on 2 off. 5000mgs a day was the regimen

    I gone from 223lbs to 212. Per skin fold test Im 8.06 [21 pinch, 7 site test] and from the same person I was 10.24

    Only thing I bumped up was hydration after review I not hydrating enough.

    Side effects, have been a curious heart flutter which at first was weird. After some looking into it it is a small but obvious side effect.

    I anticipate blood work soon to assess lipid panel and triglyceride levels. I get most of my panel see if there are any weird correlates from the MCT’s.

    1. Palpitations are fairly common when first entering a ketogenic state. This goes away for most people fairly quickly. I had this problem initially as well.

  13. This is awesome Tim! Are you still on the SCD or do you switch around? I’m a big fan of SCD + KB training…really good way to look good with minimal time investment. What kind of workouts and diet are you currently doing?

    1. Totally 100% SCD, though I often omit the beans or lentils, as I am consuming a high % of calories from fat. For training, I’m doing mostly KB swings, 2-5 rep compound movements (a la “Effortless Superhuman” chapter in 4HB), and sport (e.g. rock climbing).

      SCD + swings is a great minimal effective dose, for sure. Few things beat it for minutes invested.

      Keep it up!


  14. I’ve experimented with one before and concluded it a losing proposition when competing in athletics (demanding anyways), mainly because you will require CHOs if using a mix of power and endurance modalities. If a sport required less dynamics, a more steady-state, then I can see how a ketogenic approach may be undertaken. To me, it would depend on the quality and quantity of all-out efforts required by your undertaking. On a side note, one thing that gets lost in the macronutrient wars is food reward theory. Instead of thinking about diets from a typical macro-perspective, it is important begin to understand the organ that probably mediates all diets effects, the brain. I experimented with keto-dieting when “revisiting” competitive tennis (an ex-college player) and I feel it limited my efforts in significant ways.

  15. Ketosis has worked very well for fat loss, better than slow carb but harder to sustain. My body seems to sustain on slow carb not lose, but ketosis definitely gets the needle to move.

    Thanks for posting this resource, and for all the excellent discussion that’s bound to follow.

  16. With true ketosis, you can’t really even eat protein, because your body will fight ketosis *so* hard that it will take all available protein and convert it desperately into carbs.

    If you really want to box your body into a metabolic corner, then sure, go for ketosis, but you’re really limited to eating just fat. Otherwise, you’ll pop right out of ketosis.

    A high protein diet without carbs is essentially still a high carbohydrate diet, it’s just going to put a ton of stress on your liver in the process.

    And, think about this: If you don’t eat anything, what are you living on after your glycogen stores are depleted? You’re living on *yourself* when you are starving, and you are made of protein, and fat.

    So if you *eat* only protein and fat, aren’t you just “simulating” starvation, on a metabolic level?

    Ketosis is a fad unless you’ve got a real medical reason to use it, it’s probably a good idea to not mess with your metabolic function to that level. You’ll probably be kicking yourself in a few years when you start wondering why you can’t eat carbs, or higher calories anymore without packing on fat.

    1. Have you done keto?

      You *can* eat protein on keto, as long as you stay within your personal needs. It is not a fad, and it works for some people (I’m not saying that it will work for anybody).

      Also, some people might have better results by doing any other diet.

      It works for me, and a lot other people. Look up /r/ketogains and /r/keto in reddit for lots of success stories. 😉

      1. FWIW the science isn’t settled on this either – AFAIK. The accepted dogma is that GNG drives blood sugar up with excess protein, but mostly it’s extrapolation of noticing that blood sugar rises on a meal of protein. Especially in the arena of ketosis which is even less researched, GNG on anything but an infintessimal scale doesn’t seem logical – if there’s enough fat available (which produces glycerol and ketones as a by-product) then the reason for the body to use a very metabolically expensive process to rip apart structural proteins for it’s glucose seems absent.

        Very few people question it – even fewer studies and journals – it’s just accepted that GNG is the fate of “excess” protein, but we’re relying on a theory mostly:


        This blog post includes a graphic of all the places different amino acids can feed into the Kreb’s cycle, etc.

        There is no evidence that gluconeogenesis is substrate driven, and it is certainly false that excess protein must be converted to glucose to be used for energy (or stored as fat).

        Also some AA are ketogenic, notably the BCAA’s. Dairy and beef would be good choices for protein sources then …

    2. You obviously don’t know what you’re talking about. I consume 100-150 grams of protein and about 30 grams of carbs a day but still remain in ketosis with little to no exercise. I don’t use ketostix. I test via blood using the Precision Xtra 2x a day.

    3. There must be something off in your assumptions, because for the past few years I have typically eaten < 30 g of digestible carbohydrates (i.e. not including fiber) per day and my strength is not all that bad, nor have my muscles atrophied to the extreme, as your analysis implies they should have.

    1. The slow carb as described in 4HB does not lead to ketosis. Probably only 1 big serving of beans/lentils per day is enough carbs to keep you out.

      To dip into ketosis, your diet pretty much must consist only of meat and veggies – maybe with some nuts or something. Eat plenty of fat. Always buy organic.

  17. I’m a relatively competitive powerlifter and I’ve been training 4 times a week for the past 7 months pretty much always in ketosis and almost always semi-fasted. When I started in January I was 200lbs and I just competed in a powerlifting meet at 183lbs after a 2lbs water cut. I unfortunately didn’t take measurements but I’m almost certain I’ve gained some muscle while losing fat on this diet.

    The only problem that I have with ketosis is that I don’t sleep as well. Using my fitbit track my sleep efficiency is always below 50%. I’m wondering if anyone has any tips on improving sleep quality while on a ketogenic diet?

    1. Some people fare well with Raw Honey in small amounts before bed. Also, some people have used Trehelose before bed as well. This is to give you body just enough glucose for the brain while sleeping. I don’t have personal experience with this but I can share sources of information on this. Also, many have tried non-denatured grass-fed whey protein concentrate, collagen protein, and/or mct oil before bed as well as certain peptides.

      Are you supplementing magnesium? Magnesium glycinate helps my sleep tremendously, as does cold thermogenesis. Also, sleeping in a completely pitch black room with limited EMFs nearby you, and possibly eliminating blue-light frequencies prior to bed (i.e. use blue light blockers, f.lux, and turn lights off unless using amber bulbs or candles).

      Hope this helps!

  18. Years ago I was annoyed by the constant “meat and fat will kill you bro” rhetoric so went in search of proof that would tell me either way that I couldn’t eat steak every day.

    Took a while, but eventually I stumbled upon an article by Stefansson from 1935 about life on an all-meat diet, and subsequent clinical tests on all this stuff. Changed my life.

    The article could be written today – it’s full of the same feelings of incredulity toward the established dogma of “eat a balanced diet” and all that BS, at least back then people weren’t yet exposed to many of the frankenfoods we’ve got the population running fat and sick on nowadays.

    From there I went head-long into research (he also wrote a couple books) and the more I read the more I realised that steak wasn’t just something I *can* have now and then – it’s something that *should* be a staple. I immediately cut sugar and processed starches, then over time slowly reducing my veggie intake to settle where I’ve been for the last couple years – 95% carnivore (I eat broccoli and pumpkin once every week or so) and ketogenic.

    The original article available here:

  19. I have followed a ketogenic diet before.

    The good stuff: I was never hungry. Literally no cravings or slumps ever. Lost lots of fat. Got cut without effort.

    The bad stuff: pretty bad breath. More expensive to get quality fats (organic saturated fats).

  20. I did a leangains type IF with low to no carbs for about 6 months. It was terrible. I gained weight, was terribly depressed, etc. Once I embraced simple sugars, I lost weight and depression lifted. I think aiming for ketosis is absurd and will eventually damage metabolism.

    1. I don’t think Tim or anyone advocates for no to low carbs for that long. Most people recommend at least one re-feed per week, oftentimes more. Martin of leangains cycles b/t low carb and high carb days depending on training, did you do that?

    2. Leangains is not “low to no carbs”… It’s more about intermittent fasting, carb and calorie cycling. On non training days it can be around 70 grams of carbs in a caloric deficit, and 350 grams on training days in a caloric surplus (I’m using myself as an example, cutting).

      1. I should have been more clear, when I said lean gains I was referring to the timing of the IF. Refeeds didn’t solve my issues either.

  21. Holy shit that was interesting. Thanks so much for sharing! Definitely one who loves this, will have to research more & try the state myself.. 😀

    1. Homocysteine levels will rise due to dysfunctional protein metabolism via inadequate protein intake (resulting in hypocysteinemia) and inadequate B12 absorption, which meat- especially red meat carries. The Clinton diet will lead to stroke if not careful.

      Also, researching fats and their effect on health in a cutting edge facility, I can vow for isolated fats made into oils (unrefined, that is), that they are critical for hormonal signaling, insulin sensitivity, and epigenetic expression- although I entirely agree with removing the oils with high Arachidonic Acid content, such as corn oil, yet Dihomogamma linoleic acid interconverts to GLA to produce counteractive eicosanoids that prevent proinflammatory arachidonic acid. In addition, anti-arachidonic acid stems from EPA and DHA, and EPA and DHA bind to GPCR 120 to recruit glucose transporters to the surface of GPCR 120 expressing cells. These transporters take glucose out of the bloodstream into cells- preventing hyperglycaemia and hyperinsulinaemia which both cases are highly inflammatory and cause oxidation of lipoprotein particles, shrinking LDL lipoproteins into their “bad” state. These “bad” LDLs are then able to get caught in lesions and become unable to repair tissue and deliver fats and cholesterol- which is their designed purpose- and cause plaque formation, and start atherosclerosis.

      Sorry to rain on your biased opinion, but knowing doctors (my boss/PI, my father, and I work with them), they often (some still do, this doesn’t pertain to all) don’t care for the science and would rather learn how to just treat the condition, and it seems these two men have that mindset and would rather just get money for their “input”. The diet may be beneficial, however, to people who have highly dysfunctional LDL receptors, though.

      1. “Homocysteine levels will rise due to dysfunctional protein metabolism via inadequate protein intake”

        Inadequate protein intake is what exactly? The WHO recommends 6% of calories from protein is more than sufficient. Most fruits and vegetables contain more than that. There isn’t even a medical term for protein deficiency. Malnourishment, yes, but not protein deficiency. Homocysteine levels are typically higher in high-protein type diets.

        B12 deficiency is just as common in high animal protein diet eaters as it is plant based diets. If eating red meat is a good source of B12 for us, this wouldn’t be the case. B12 is also present on the surface of unwashed, organic fruits and vegetables. All the pubmed links you posted support the reasoning behind a “Clinton-type diet”(a wholefoods, plant based diet) as healthier than a high fat/ high protein type diet.

  22. Tim (and everyone else), I highly suggest looking into the work of Dr. Jack Kruse – very few (if anyone) has really looked into the implications for performance that ketosis can offer in the PROPER context. He has a blog and has done podcasts with Ben Greenfield – he also has an extensive cold thermogenesis protocol. To be brief, ketosis+cold thermogenesis (Dr. Kruse style, not Ray Cronise style)+an ‘epi-paleo’ diet would be the way to go. The deep cold thermogenesis would drive up thyroid production and knock down rT3 and increase fatty acid utilization, RER, and VO2 max; the seafood heavy diet provides iodine, selenium, and the fatty acids needed – also in a ‘cold adpated’ state, according to Kruse’ work of course, the body uses PUFAs better in cells to maintain fluidity. Barry Ross, who Tim has spoken of in his books, frequents Dr. Kruse forums and speaks about the implications for sports performance.

    Other notable people/protocols to look into are that of Dave Asprey and Ben Greenfield. Here is Ben Greenfield’s current ongoing ketogenic experiment: He recently set a PR in Japan.

    The more I learn about epigenetics and nutrigenomics, the less I believe ketosis is ideal for EVERYONE, because certain alleles may actually create an environment for your body to be consuming less fat (ApoE4 allele I believe). Dr. Kruse speaks about this and his ‘epi-paleo’ diet is largely based around seasonality, personal genetics, goals, and labs, and georaphic location… i.e. someone in winter who doesn’t have some sort of pathology would be eating a strict keto-diet and doing deep CT (exposing yourself to the weather, ice baths, cold workouts) and in summer would be eating a lot more calories AND carbs through foods that are only grown locally (you wouldn’t be eating banana’s if only wild berries are the carbs in your area).

    I have been using some of these techniques myself with resistance training and martial arts (BJJ) and seeing improvements. If the circumstances weren’t as they are in my life right now, I would quantify everything much more intensely. I plan to blog about my “experiment” in the future, after I learn how to organize it a bit better and after I screw around with his tDCS device I found for $39;)

    Thanks for the great material Tim! I plan on using your language learning tips + tDCS (and bulletproof coffee after I get some money, lol) to speed learn Polish! Your blog/books are amazing, write another one, lol!

    1. Thanks for the thoughtful comment, Jacob! Kruse’s work is interesting, to be sure. On the tDCS front, I’d be careful there. I’m actually funding and participating in tDCS studies at a top university in SF. Done improperly, it can hurt performance, and no one knows the long-term implications. Not trying to stop you, but I’d encourage a lot of research and perhaps waiting 6-12 months for more data. I know it’s coming, as I’m quite involved.

      All the best,


      1. Jack Kruse is the biggest bullshitter you have ever come across. I think he suffers from some mental issues as the tripe he comes out with has to signify some deeper problem.

      2. I have. Great stuff. His CT protocol rocks, and his emphasis on getting our circadian clocks working right to engage the PPP deep fat burning pathway is a huge missing puzzle piece in most people’s perception of fuel and performance.

        I’m still working on getting my clock reset (sleep quality and hormone labs are the key indicators), so I can access that pathway efficiently, but I’ll get there. The changes in perceived fule needs, so far, are stunning. But still a long way to go.

    2. Thanks for the info about Jack Kruse,[this is why i love the 4hww comments section! awesome people in here] looked up his website and 3 hours later was very impressed. Especially CT-6 which even Doug Mcguff praised [see the comments section]

      I know thats a little bit Argument from Authority but if you know someone who knows more than you in a particular area of study, may indeed have a better method of evaluation for data collected, and conclusions drawn

  23. I’ve been doing the ketogenic diet since about late 2001.

    I was introduced to it by searching the web and found out about Dan Duchaine, Maurio Di Pascuale and eventually Lyle McDonald.

    I’ve been doing CKD all this time and about a year ago I switched to TKD with great success. I body build for hobby, and only with these approaches have I been able to stay between 10-8% body fat all year long, while increasing my muscles.

    We have a small space on reddit devoted to this, (/r/ketogains) where our main goal is to help other people excel in the sport of their choosing, while using a ketogenic protocol.

    So far, we’ve had lot of success stories and we look forward for even more 😉

  24. I’ve been experimenting with doing a bit of carb cycling lately, eating brown rice on the days where I do heavy lifting and then staying totally paleo the days that I don’t. It’s worked extremely well so far, we’ll see how it goes from here.

  25. Great video. Thanks for sharing it Tim.

    Most recently, I’ve been doing a keto-focused, intermittent fasting regime with a CKD perspective. For energy and concentration, and recovery, it has been phenomenal, but not so good for fat loss.

    Peter Attia also did a more accessible talk about insulin resistance at a Ted conference:

    I absolutely love what he’s doing with, and hope that the message propagates out through every channel possible.

    Just read today that the average Canadian doctor is grossing $370k/yr – I struggle to understand what service they’re providing for their millions of overweight patients. Kudos to Peter and his mission!

    Cheers, Luke

    1. To be fair I really doubt fat people go to the doctor to lose weight, they go for other maladies.

      As a doctor (GP) mate of mine who does a ketogenic told me – “Doctors are experts in illness, not health.”, and said that out of his near decade of study he was never taught more than 20 hours of nutrition, and most of it was just “eat less, move more”.

      1. That’s a great way to put it. Excellent expression… and not necessarily a knock on doctors. One can’t be expert in everything.

  26. Tim, you should check out my Great Ketogenic Ironman Experiment…google it. You’d get a kick out of the biohack.

  27. I believe that some of the smarted people on the planet on this topic are Truly Natural Competitive Bodybuilders and Physique Artist. I being one have studied how far I can go into Ketosis and then implement a “Starchy Carb Reload” to keep and even build muscle mass going into a show and get down to 2.5% – 4% body fat. Every Natural bodybuilder eventually realizes that Starch Carbs is the Anabolic factor that allows us to get “Intense Work outs” in while still getting lean at the same time… Call it experimentation or Bro Science.. Carb Cycling strategy is def the key for athletic performance.. Great Post Tim..

  28. I find 2 carb ups during the week works best, one small one Wednesday night, one large one throughout Saturday. This is with a training schedule Mon, Tue, Thu, Fri. I’ll do an upper body workout one day followed by lower body workout the next, preferring compound movements like squats and chin ups, and glycogen deplete in these workouts as much as possible, stacking weights for pyramid style training. The break comes in on Wednesday, where I don’t workout, but I have a small carb up in the evening to better perform in Thursday’s and Friday’s workouts. My metabolism/genetics are quite carb sensitive, so my carb ups involve low GI beans or sweet potato- if I hit pasta or rice I can’t shed fat (I might even put fat on!). I also fast 16/8 as per Martin Berkhan, although I don’t think it’s necessary to also fast in order to lose fat on the CKD. A few times I have done a fat fast, Atkins style, which I have found very effective, but a challenge psychologically the first few times! Pesto is a good food for that.

  29. Keto is not optimal for high-intensity training performance. Nor is it optimal for the best possible experiences in Italian restaurants.

  30. I have tried a ketogenic diet and intermittent fasting and never had a good experience with either. I know it some situations and I think with the right genetics it may be worth.It always made me feel terrible. I do have a number of mutations which affect me methylation and detoxifaction which cause a plethora of health problems.

    That being said I do tend to have a lower carbohydrate diet but I think different people need different amounts of carbohydrates based on health status (blood sugar problems, thyroid problems, genetic issues such as myself), levels of activity/exercise and how it makes them feel on a day to day basis. Some do better with lower carbohydrates and some with more. Generally though if you have blood sugar issues (many people do) its best to go lower carbohydrates to stabilize blood sugar.

  31. I have been a strict adherent to the slow carb diet since Tim’s original “How To Lose 20 Pounds In 30 Days” post. The SCD helped me go from 245 pounds to 160 pounds within the first year. Unfortunately after that initial weight loss, I plateaued at around 160-165 pounds and was never able to lose any more body fat. I am only 5’6 and at 160 pounds I have a considerable amount of belly fat that manifests itself as a spare tire and love handles.

    I have tried everything to lose this excess fat. I tried the diet plan in “The Last Mile” presented in The Four Hour Body for over 2 months and saw no changes in body composition (weight or inches using the body measurement techniques outlined in 4HB). I tried cardio for 6 months, building up to distance running of 55 minutes every other day which culminated in an Achilles injury. This created no body composition changes either.

    I started weight lifting using Tim’s workout plan from 4HB 9 weeks ago and have made significant strength increases. Unfortunately the scale has stayed in the 163-165 pound range throughout. The tape measurerer shows minor gains around my biceps and thighs, but my navel measurement has remained consistent throughout and my before pictures show a striking resemblance to my current pictures… It should also be noted that I began intermittent fasting with 8 hour feeding windows – still adhering to the SCD – at the same time I started weight training.

    I guess my question is, would ketosis be a good option for me to break through this 2 year + fat loss plateau and help me get from the mid 20s body fat % to the low teens?

    1. Hi Jonathan

      I’ve used the Effortless Superman and also a version of Hypertrophy recently while hardly changing my diet to get bigger. Slow reps under tension helped build me up (10 lbs in around 6 weeks – aided by a month of 1 teaspoon of creatine in the morning). I don’t eat beans (just brown rice) and carb cycle (just a bit) but follow the SCD ideas fairly well. I have noticed more definition even though I’m heavier due to a small amount of muscle growth. So looking at what you say the answer may be to change your workouts to lose fat rather than diet.

      Strength training doesn’t necessarily build size, you may need to spend more time under tension (hypertrophy) and maybe even do a few weeks of “pump” (the typical 3 sets of 8 to 12 at 50 to 60% of 1 RM). Now I know that this may not be strictly in keeping with 4HB but remember that you seem to have been training for a while and plateauing…so what worked before doesn’t necessarily work now.

      On the plus side if you build bigger muscles it should translate to more fat loss for the same diet. That is what I read about and it seems to work for me. But that’s something you need to test – like I said try changing your workouts to do more higher volume resistance training (not cardio) but don’t change your diet.

      Oh and for reference I went from 12 st to 12 st 10lbs (I’m still around 13 to 14% bodyfat). I actually look a bit more defined now than I did. Go figure!

    2. Jonathan,

      I agree entirely with what Mickey Said. You have to adapt to what works best for you. Another thing I would like to add to this is that you may consider Cold Therapy (CT) experimentation. Like mentioned in some of the comments above. I don’t know what your supplement regiment is but you should look into that for potential answers to your plateau issue. You might be deficient in something you are completely unaware of.


      Jonathan Reichel

    3. Hi Jonathan,

      You might want to give a try on Ketogentic diet. I was in similar situation you are and tried keto diet (Cyclic Ketogentic Diet, CKD) more than 12 yrs ago.

      I was 220 lb(@5-9 1/2) 12 yrs ago and started sort of moderate low carb + high protein diet (somewhat close to sears’ Zone diet at that time). With this diet and exercise, I was able to go down to around 185lb within 6-7 month time frame. During this time period my bf went from 30% to 19%. But, I hit the plateaued at that point. Actually, weigh loss itself wasn’t totally plateaued (slowed but not stopped). I wasn’t loosing much fat. My body composition was not changing anymore for more than 4 weeks.

      I switched to CKD at that point after reading the Lyle’s book. I stayed on that diet for another 5-6 month and was able to drop my bf to 14%. So it worked for me to break plateau. Since SCD is somewhat close to what my diet (difference was inclusion of low GI complex carb & moderate fruit) was before I switched to CKD, changing to keto diet might help you to break plateau.

  32. I spent 3 months last year in ketosis strictly following Jeff Voleks idea of a ‘well formulated low carbohydrate diet’ from his most recent books on the topic. Besides being ridiculed by my fellow Dietetic colleagues, I found I leaned out from around 17-18% down to 13-14% (confirmed by bodpod) despite over eating and not really trying. Didn’t lose any LBM either which was interesting.

    In terms of gym performance, I found that I maintained all of my strength but my ability to perform repetitive movements was severely limited. Reps went from 8-12 to 4-6 of course due to being severely glycogen depleted.

    Whilst I’m of the opinion a ketogenic diet has a therapeutic place in the world depending on the clinical context (especially in the case of epilepsy, insulin resistance etc), it is for most people not necessary if all that someone wants to do is lose fat. That can be achieved every simply by: eating plenty of protein/fat + timing carbohydrates around some form of training. Of course insulin resistant people will of course benefit from being on the lower end of the carbohydrate scale.

    1. Mike- This post made me so happy. Carbs are not bad. I love Tim’s work and think it has its place for sure. I had lots of success with it. Ketosis for me is more therapy than a performance boost. Volek and Phinney’s work is laughed at in the endurance community fyi.

    2. I am familiar with the ketogenic (or Modified-Atkins) diet solely because my son had epilepsy and we had discovered this as a treatment when searching for any non-pharmaceutical alternatives. For the year we’ve been doing it, it has been 100% effective in eliminating the seizures. I couldn’t begin to explain the science of it, all I know is that it has worked for him.

      I am curious now to research and possibly try this for myself for the fat loss and muscle-gain aspects of it.

  33. Totally non-scientific but remarkably powerful observation about the long term effects of ketogenic diets.

    I spent an afternoon about a year ago following the muse around YouTube watching the ketogenesis people speak their piece. I’ve done every diet known to man since losing 100 pounds on The Zone in 2002. My degree of obsessiveness does not match yours, Tim, but is sufficient enough to make everyone around me think I’m at least a little off.

    After about three hours of listening and observing the experts as they explained the benefits of their program my spidey sense began to fire. It took another half hour and a sudden dive back through every video that I had seen for a few moments each to realize this: the longer the presenter had been doing a ketogenic program the older they looked. To a man (or woman) they all looked OLDER than their age, not younger. Prematurely gray hair. Age lines. The whole package.

    I decided that was an important clue and that it trumped all the science ever written about the efficacy of the diet as no one has done a fifty year study of ketogenic diets while looking for aging markers.

    Here are my bona-fides. Last pair of images was a round of the SCD last year.

  34. Tim, thanks for beating this drum! I carb up every 5th night. It has been hugely effective for me… has allowed me to eat as much as I can while still getting down to ~7% bf. Mean while my strength continues to climb (400+ squat, 500+ DL, 385 bench).

    If anyone needs help with coaching or would like more info on how to put this type of program together feel free to contact me.


  35. Here’s something I’ll never get. Why are people so impressed by MDs who brag about learning nothing useful in medical school and then lecture folks on all the nutritional science they didn’t learn?

    On his website, Attia discusses his reduced performance in ketosis. He then began using superstarch (e.g. carbs is carbs) sometime late 2011 to improve his performance. So much for ketosis being some exalted advantaged metabolic state. I can’t help but point out that he has now extended his n=1 weight back to 2003 and included a low in 2012 to get his 40 lbs. In reality, doing the ketosis thing April to August 2011, he lost about 7 lbs — 4 fat, 3 lean.

    Misleading title for that video then …

  36. I’ve experimented with CKDs and the SCD and everything in between since Dipasquale was working with the Vince McMahon bodybuilding federation and the “High-Fat Diet” was being pushed by Leo Costa Jr. In the Serious Growth program (workouts not recommended:D ) and Lyle mcDonalds books.

    Anywho, after many “carb-in” years between I returned to low-carb dieting last after reading 4HB and rekindling my interest in losing fat and getting into better shape.

    By far the greatest adjunct to low-carb dieting I’ve found is Dave Aspreys Bulletproof Coffee.

    The current plan I’ve been following with superb results has been …

    Diet – 30 grams of protein within 30 minutes of waking a la Mr. Ferriss followed up by Bulletproof coffee about an hour later right before I leave for work.

    I usually have some sort of caffeine in the afternoon that prolongs the lack of hunger that starts to kick in around 230-3.

    I eat dinner which consists of meat and low-carb veggies.

    Occasionally I have a spoonful of natural peanut butter if I’m up late.

    That’s it six days a week. Seventh day (Sunday) is the cheat day. Noon to midnight usually. Anything goes.

    Workouts – twice a week ~ 20 weight workouts, every third week I do three and every fourth week off.

    Kettlebell swings one exercise each for shoulders, chest, bi’s and tri’s. all negative only 🙂 save the swings – which in essence are negative- accentuated hence their effectiveness.


  37. The talk by Peter Atria was fantastic! Thank you so much for posting. I usually lose interest in this kind of talk and don’t make it through, but he’s a great speaker, and I felt compelled to watch it all, and got a lot out of it. Really, good stuff. Cheers!

  38. Over the past 12 months I’ve lost over 75 pounds of fat, and gained 30 pounds of muscle, a 100+ pound turnaround, using a ketogenic diet, with a once a week carb load all you can eat junk fest. I’m so bloated by the end of my cheat day I can barely walk, and by the end of day 2 I’m back in ketosis ready to rock. My diet/workout plans are taken from a few different sources. Diet is taken from dave Palumbo. He recommends the fats come from eggs, peanut butter, nuts, and learn meat/fish, also the fat % isn’t as high as Duchane or McDonald recommended. I get around 130 grams a day and I’m 195 pounds 10% bodyfat. I keep protein at 300 grams. I stole my work outs from Lyles Ultimate Diet 2.0, where he has you do a full body workout Monday and Tuesday to deplete glycogen and rapidly establish ketosis. People don’t realize all the body holders of old ate ketogenic diets, including Arnold himself. Just YouTube Pumping Iron and look for the restaurant scene and pay attention to what they ate. It’s all there, there’s no better way to get and stay shredded while gaining and retaining muscle. Email me and I can give you my full story and workout diet regimine.

  39. Having used ketogenesis before in the cyclic form, I completely agree with the doctor’s statements about the “feeling” you get when your brain is on ketones. Thinking of going back!

  40. Wow! What an interesting and informative presentation! (Even though I didn’t understand much of it). 🙂

  41. I’ve done keto on and off for the past year or so. I haven’t done the carb-loading portion of it because I’m not exactly athletic, but I do have designated cheat days. I have trouble coming back from those cheat days though sometimes (mentally) so I try not to have them at all unless I hit a plateau. Best “diet” there is if you ask me, you’re never hungry without carbs, they truly are addictive.

  42. Ketosis rarely works for people that are very fit. It works wonders for the obese that have to lose 50 or more lbs. We need carbs at some point to facilitate weight loss. Not to mention ketosis all the time just makes your muscles flabby and hurts strength gains. Once in a while I think it might be therapeutic to dip into ketosis but definitely not all the time.

  43. I have dealt with a lot of keto diets in my day both personally and with my patients.

    I have a broad spectrum of patients from extremely obese to bodybuilders. I have seen it help the most metabolically diseased folks and also help a handful of athletes.

    I have also seen it destroy the metabolisms of healthy patients as well causing some of my obese patients to have major thyroid issues and women to lose their periods. Many of my athletes lose muscle and strength as well.

    It is a powerful too but should be used as needed. Folks should be very careful and be in tune with their bodies.

    1. Thanks for sharing that. I continue to be impressed at the variability of human function. Each body is different – with a limited continuum of possible choices. You are persuasive. Perhaps it’s the white coat in the picture. LOL

      1. hehe thanks I should have put the stethoscope on my shoulders to add effect 🙂

  44. I am fairly familiar with a ketogenic diet as I train and support physicians to implement a ketogenic protocol for weight loss, but primarily to address metabolic syndrome.

    I’ve been living an extremely low carb ketogenic diet for the past 4 months that I have been combining with a daily intermittent fast of typically 18 hrs up to 21. I am loving living in ketosis. I have yet to experience a downside.

  45. I’m a marathon runner and this video really piqued my curiosity. I’ve hit the wall (bonked) so many times and would love to somehow avoid it – or at the very least put it off till mile 25 🙂 Gonna incorporate this into my current training cycle.

    Dr. Attia mentioned on his blog that ketones could also be increased via supplements (not raspberry). Which supplements help to increase ketones?

    1. Medium chain triglycerides – they don’t digest like normal fats, they basically slip straight through to the liver and quickly metabolise to ketones and stuff.

      Coconut oil is full of them, or you can buy MCT oil which is a concentrate and without the coconut flavour – actually as far as I can tell it’s completely odourless and tasteless.

      I’ve been intermittent ketogenic for a couple years now and never really noticed MCT oil doing much for me even when shotting a few tablespoons of it, however coconut oil gives me digestive issues – oddly enough it’s the other way around for most folk as far as I can tell.

  46. I think everyone should be skeptical just from a quick defense protocol. My GF is constantly (every week) tossing new “diets” over to me to evaluate, so sad.

    However, having said that, if you have read Timothy’s books 4HR WW, 4HR Body, and 4HR Chef, and watched Diggnation, and watched Foundation, and watched the “Random” podcast, then you can gain a far bit more contrast to what Timothy is blogging about.

    I am always skeptical of anyone’s claims about anything remotely related to diet, exercises, or even health in general. I’ve personally lost more than 150 lbs, not even using Tim’s methods. Does it mean my program was right, or even portable to everyone, of course not. Be skeptical and question everything, please.

    This is a great post, and Tim, thanks for adding this video. (I watched the whole thing and it was valuable to me).

    I have done experimentation with supplements and their behavior for years, and was more than accepting when I read 4HR Body and saw what Tim was doing. Simply incredible, and I was jealous to say the least.

    This info in this video is not only relevant, it truly is ground breaking. If i had a 100K to spare I would be investing in Peter’s foundation right now.

    Timothy F, thank you for everything you have done so far and all that you continue to do.

  47. Very interesting presentation! He left me with several questions:

    -what was his fat breakdown? What is his percentage saturated/unsaturated/etc?

    -As per my experience, ketosis leaves you HUNGRY. 4000 kcal/day sounds about right. How did he deal with the immense amount of kcal required?

    -Ketosis also leaves you with an intense desire to binge cheat (bonk). How did he deal with that without blowing his diet?

    1. I’m never hungry on keto, nor do I ever have a desire to binge or eat a cheat meal. 100lbs lost in a year of keto + caloric restriction, now on keto at caloric maintenance since (i.e. staying on keto, possibly for life). Anecdotes are not data.

  48. Big fan of high fat diets, fat is brain fuel so therefore low fat diets are for dumbasses 🙂

    Great article!

    1. Roddy says “Besides carrots and salsa, I never eat vegetables, mainly because I’m lazy and I can’t think of any reason why I would want to include them in my meal.”

      As a carnivore I agree with the that, but he outlines a typical day’ish of eating which includes 1-2L of milk, 1-2L of orange juice, some white sugar, 1-2 Mexicokes (whatever they are)? The rest sounds like actual food.

      To think a ketogenic diet interferes with cellular respiration compared to up to a gallon of milk and OJ and sugar and soft drinks (?) is kinda bananas innit?

  49. Disappointed I’m reading this late. I met you at Google and asked about intermittent fasting if you recall.

    I’m curious how fasting affects body composition. From personal experience have been doing intermittent fasting with low-moderate exercise for well over a year with paleo. Recently, as soon as I switched to a full day fast after my cheat day I noticed my body changing composition, not weight, but I felt I developed less abdominal fat.

    I’m curious on trying different fasting methods (many here in bbc documentary) and their effect on myself and others. Would be a great crowdsource project Tim if you gathered groups of folks and tried fasting methods with those folks and then based on feedback had them try another method. Questions I have developed for myself based on my recent fasting experiments:

    -Does when I eat/fast matter more than what I eat?

    -Is a method where I fast for full days more effective than intermittent fasting?

    -How does all the above affect my biometrics?

    I have genes, per 23andme, that lend themselves to high triglycerides and carbohydrates and my number 1 disease I am subject to is coronary heart disease (56.7%).

  50. Hey Tim,

    not talking right now about this topic but…

    Are you in Recife – Brazil?!?!?

    I swear to God that I’ve seen a guy that looked so much like you last week in a steakhouse restaurant.

    I’m a BJJ fighter here in my city, so if you are really here for a time and want to train in our gym you are very welcomed! =D

    You have my email if that was really you! hahaha

    Anyway, your book changed my life! Thanks for sharing everything you do! 🙂

  51. I have experiemented with low carb diets. It takes some getting used to especially when you train hard. I usually workout 4-5 times a week, including endurance training and find I need the carbs just to fuel my workouts. I guess if I was less active than I wouldn’t struggle so much.

    I now follow a modified ‘carbohydrate cycling’ diet which enables me to focus on vitrtually no-carbs on non-training days and medium carb intake on training days. It works well for my needs and is sufficent to encourage ketosis. I’m down to 8% BF and energy levels are fine. I guess you have to experiement a little to find the right nutrient intake for your body type, size and energy needs.

  52. Admittedly, I do not suffer with excess body fat. I am an avid practitioner of mountain biking and hit the weights twice in an average week (slow movement, 9 lifts, whole body per work out). For the sake of full disclosure, I may have a genetic predisposition for low body fat and general health.

    While I do not argue against the short-term solutions offered by the high-protein, paleo-esque diet – I do believe it is worth asking a simple question: how do I weigh my long term health against my desire for immediate satisfaction? As an athlete, I have enough anecdotal evidence to suggest that high-protein diets (Paleo, et al.) will produce phenomenal body alterations in the shortest amount of time. In our days roaming the sub-Saharan continent, access to high-protein foods would have been intermittent. These diets likely prey upon systemic frameworks targeted at taking advantage of these occurrences to generate growth and fuel the androgenic system. However, I do believe that there is continual evidence to suggest that diets aimed at utilizing these systems over long periods cause the body to deteriorate over the long term. Remember: evolution does not care about humans in their late 20’s or 30’s. Once you and your prospective mates produce 1.1 viable children, you are considered an evolutionary success.

    As Mr. Ferriss is sure to point out, time is our most precious resource. I agree whole-heatedly with his sentiment. Therefore the question of health and diet must be re contextualized: how do I weigh my desire for immediate results against my goal of “useful longevity”. I would suggest that unless you are a professional athlete, you consider our unnatural access to raw “superfoods” from around the world. By leaning toward a nutrient rich, raw food diet you may see a marked delay in immediate muscle building or fat loss – however I plan on using this plan to continue athletic performance into my 90’s and beyond.

  53. 2 questions regarding athletic performance & ketosis.

    I follow SCD, Effortless Superhuman and play a crazy, crazy sport called underwater hockey ( , the first 2 min should give an idea of the intensity and game play) and I suspect ketosis might solve one of my biggest problems.

    A weighted puck is pushed along the bottom of the pool by people wearing fins, masks & snorkels. No scuba gear allowed. One of the keys to great play is an excellent breath hold. Being able to stay under 20 sec is good. 30 secs? Never mind 80-20, it’s more a 98-2 kinda situation. The pay-off in a 10 sec breath hold at max intensity would be huge (and so would being able to do it again after 5 breaths). So I’m really keen to sort that out.

    Would a state of ketosis help me get that extra 10 secs? From what I understood in the talk, it might but all Dr Attia’s cases were for 60% intensity over longer periods of time or for high intensity with constant access to air (plyo stuff). In underwater hockey the effort to propel yourself (+ puck) at speed makes for high intensity without O2. Sometimes you stay under for 20 sec working as close to max, come up for 5 breaths (sometimes there’s only time for 1) and down again. On perceived exertion scale: Often not able to talk (even if it hadn’t been underwater I’d be too out of breath). If I manage to talk, it’s hard to do so.

    Typical game time (tournaments): 20 – 30 min

    Game time (weekday practices): 60 – 90 min

    My second question is am I understanding him correctly if I say that ketosis helps with post exercise recovery? Weekday practices are Mon, Wed & Thurs nights. On Thursdays my in-game performance is down (subjective observation: I feel tired, can’t out-swim poeple as often and bottom time is shockingly bad) and on Friday mornings I struggle to get out of bed. Would ketosis improve the kind of recovery? I’m currently playing around with when I cheat but so far no noticeable improvements.

  54. Awsome video tim, thank you for sharing. I honestly enjoy learning more about the impact of nutrition on my body. I recently started a routine to change the way I eat to fuel my body. I got your 4hB (& 4HC) and planning to change and tweak my diet, in addition i am also interesting to follow the concept behind Dave Asprey´s Bullet proof diet. Though I must admit I get overwhelmed sometimes with the information there is.

  55. How can you guys stay in ketosis if you load with carbs at all? It’s taken me almost 14 days to switch over to burning fat not carbs, during which time I felt so rough, I’m actually too scared to go near a carb. But, seriously, why do you need to reload if you’re not using glycogen in the first place? I’m doing just fine, Crossfitting 4 times a week, in full ketosis, not a carb in site! And now I’m fully keto-adapted I feel tremendous. I’m doing this for performance, not for fat loss. Female, 49, 120lbs.

    1. If I’m in Ketosis and carboload and then STOP CARBS, I usually find I’m back in ketosis within 24 hours, maybe 30 at most

  56. Awesome video, THANK YOU TIM! Now I finally have a (reasonably) bite-size and credible bit of info to send friends and family who think my diet is insane.

    I’ve been doing intermittent fasting that has me in ketosis for most of the day, with a 4-6 eating window. Like some others on here, I use Asprey’s Bulletproof Coffee with butter and MCT oil as a breakfast that doesn’t break the fast, but then eat SCD foods for two big meals in my eating window. I’m vegetarian, so that’s basically beans, eggs, and veggies. Another commenter mentioned the price of coffee beans for BP coffee: Asprey’s beans are supposedly free of mold toxins, and they DO make me perform better on Lumosity brain games than regular beans… but you could get the ketosis effects with regular coffee beans, grass-fed butter, and MCT oil for cheaper.

    For anyone interested in getting most of the benefits of ketosis without an extremely restrictive diet, intermittent fasting with buttered coffee in the morning has been a great middle ground for me.

    Like Peter Attia, I LOVE the way ketones make my brain work, I’m never hungry, and I have consistent energy throughout the day. I had more cravings during the day when I had 30g of protein within 30 minutes of waking following strict SCD. Plus, now I can do sprints, lift weights, or do KB swings while fasting, just running on glycogen and ketones.

  57. Awesome Stuff Peter – Thank Tim for this awesome post. I always learn something new to help my weight loss.

  58. Hello Tim and support team.

    My question is pretty straight forward, can I take PAGG during the CKD. I competed in Bodybuilding for years and I knew the late Dan Duchaine and have read his book. With the CKD. do you differ on the Carb loading phase. Lastly, what do you think of Garcinia Cambogia. I tend to use supplements that have stood the test of time, but I made an exception with Garcinia because of the claims that have been made. If the claims are true, would you recommend taking it during CKD?

  59. Got some new insights, thanks a lot! I made the experience that “playing” with carbohydrates’ share in my nutrition has an immediate effect on well being, performance and body fat. “All or nothing” doesn’t apply. Whether it is shape, performance or health – there’s nothing else to do but to try and error to find out the best long term carb – equilibrium to support the personal goals.

  60. Dr Attia has named primal flora his probiotics of choice, for those with frequent stomach issues. says he knows and trusts the guy who makes it.

  61. Ketogenic diet worked for me very well but I didn’t strictly keep the 12-18 hours time after the glycogen depletion. Maybe it didn’t work that well, but it’s still a pretty fast weight loss plan. Especially when you train a lot

  62. Hi. I love the fourhourbody-diet. I feel really well in every aspect besides having palpitations. I have read about this and it seems many who start this diets gets them. I never had those in my life before so it must relate to the diet, and it seems that many gets them. Of course this is a matter for a doctor. But since so many experience the same problems could you give your opinion on the matter? It worries me a lot. I would love to continue eating like this for a long time since I like it, but palpitations are kind of scary…. Best, Anna

  63. I’m a bit of a latecomer to this post. I did ketosis for a couple months when I couldn’t go to the gym after a surgery. Some observations:

    * There’s a definite adaption period. You feel better 1-2 weeks in.

    * Once I was keto-adapted, it became my new “state”. If I had a bunch of carbs, I re-entered ketosis much more easily (as measured by ketostix)

    * Electrolyte balance was more difficult. I was occasionally lightheaded and had to pay conscious attention to salts. I probably should have eaten more avocado

    * Energy was pretty constant. Hunger far less pressing than on a regular diet, could go long stretches without food (and I’m already used to intermittent fasting)

    * I have IBS-like symptoms, which makes ketosis more difficult. Certain carbs, such as blueberries, seem to work miracles for my gut. On ketosis I had no idea how to fix things if digestion went awry.

    * When I went back to the gym (barbells), I experienced a crash. I went back to my usual carbs post workout diet. If I were sticking with ketosis, I’d have to pay much more attention to how to manage carbs

    * Intermitten fasting appears to have helped with keto-adaptation. I only took a few days to enter it the first time.

    Overall, a very useful diet for certain purposes. I was already lean, so no real weight loss need, but it would be very useful for anyone trying to lose fat. No hunger or cravings once you’re on it.

    Also an excellent option if for some reason you can’t do heavy lifting for a period (injury, traveling). Likewise great if you have to keep an irregular schedule.

  64. Keto was the best 3 weeks I ever had. I felt more energetic, alert, and stronger than before. I dropped 16 lbs while still gaining strength.

    It’s an incredibly difficult routine to follow. My favorite part was I could eat hot wings on a diet. How cool is that?

  65. It may be a bit difficult in terms drastically limiting your carbohydrate intake and find those types of foods you can enjoy. However, I think the benefits are much more extensive compared to the restrictions.

    It is difficult because it pushes into finding those types of foods which fit in with the ketogenic diet. And since most of the supermarkets are carbohydrate predominant, this is where it becomes challenging.

    Nevertheless, I found that dark-chocolate with 85% cocoa has only 3-4grams of net carbohydrates per 100grams (3.5oz), which means feast!

  66. Ketosis works for me on ALL levels. I wish I started sooner! It just feels diffrent and carbs make me ” mental “

  67. I like your presentation and the article as well. I will use the CKD and see how it will work for me.

    Thanks for sharing…

  68. Wow, for me this is a great news. My Zumba leaderWith the right plan and the right discipline, you can get seriously shredded in just 28 days.

  69. Palpitations are fairly common when first entering a photogenic state. This goes away for most people fairly quickly. I had this problem initially as well.

  70. Hi- I love your blogs and your podcasts. The question I have is “how long will I feel absolutely awful while exercising, after going into ketosis?” I initially only dropped my carbohydrate intake to about 125 grams per day. I did that for 3 weeks, then after reading and learning more, I dropped it to under 50 grams per day. During the 3 weeks of “moderate” carbs, I noticed that I was starting to struggle with workouts over an hour. At about mile 7 or 8 of a 12 mile run, I would feel like it turned into a death march. I tried increasing my carb intake a little (in the form of more fruit) for the day prior to a long run or in a meal 3 hours before. I still bonked at the hour point. Now that I have dropped to under 50 grams, I am not sure I could even run a mile. Do you have any encouragement or words of advice? If this will pass in a couple of weeks, I can tolerate it. Otherwise I will probably like to go back to adding a few carbs immediately before and during exercise.


    1. hi,

      Not exactly sure of where you’re at in your timeline, but based on what I have read, eating 125 g of carbs per day is 20% of your daily carb intake (I assumed 2500 calories per day, which is 700 calories more than the average American woman, since you are an athlete), which perhaps isn’t low enough to fully keto-adapt. Also, 3 weeks might not be long enough to fully keto-adapt. So perhaps stick with your 50 g carbs/ day for another 3-4 weeks and then see how you feel.

    2. Hey Kathy,

      the treshold is not necessary 50g of carbs per day, it’s individual. For some it’s above, for many people below 50g. As a general guideline I’d say the more metabolicly broken and insulin resistant someone is, the higher the carb intolerance and the lower the carbs have to be, in order to adapt.

      Personally, I kept them around 15g until it worked, just to be sure.

      Fat should be high (80% of the total kcal), protein moderate.

      The time it takes to adapt is individual as well. Too high protein, cardio training and other physical or mental stress can prevent keto-adaption. HIT in the first days of adaption-process might speed up the adaption. To soften adaption symptoms salt might help.

      Also while not yet keto-adapted and still in keto-flu MCT-oil or coconut oil (60% MCTs) do help most people, since MCTs can be used as fuel even though the body is not keto-adapted (yet).

      Good luck!

      1. HIT is great for depleting glycogen quickly which forces your body to start burning fat. Be careful with keeping it going during ketosis though.

        You need a little bit of carbs to support mucous production, which in addition to the obvious places also helps form the lining in your gut. If you do lots of HIT in ketosis over more than a couple days and don’t re-feed with carbs, watch out for dry eyes and nose. If you keep going, dry gut > leaky gut > inflammation and new food allergies. I’m not sure I’ve given myself new allergies, but I did have dry eyes and nose with a sudden, unexplained weight gain and acne. Likely a bit of leaky gut and associated inflammation.

        From what I’ve read and experienced fat metabolism can support athletic efforts up to 80% of max. Sugar/glycogen is pretty necessary for higher efforts.

  71. I’ve just started with the high fat low carb diet, and logging all my foods in “My Fitness Pal” to keep track of my ratios of F/P/C. I’m having trouble keeping the carb percentage below 20%. I eat no processed foods, dairy, breads or gluten. My diet consists of lean meats, avacado, coconut oil, fresh vegetables and fruit. Water and unsweet tea are my only drinks. How do I keep the carbs lower?


    1. Jake, I also use the MyFitnessPal to keep track of my food and one think that you should be aware of is that the 20% carbs is gross and doesnt subtract the fiber amount which is what you are suppose to do. Like avocados have carbs but they get cancelled out but the high amount of fiber so the net result is very low. I suggest you take that into consideration because you might still be at a very low net carb count. I would also limit fruit to once a week and smaller portions as the geneticly modified fruit we have today is about 200% bigger then what it used to be . Strabberies are the size of apples now and apples the size of watermelons! ..and watermelons well you might need a friend and a truck to take one home. ;lol 🙂 Good luck!

  72. I experimented with both low and high carb diets, most recently with rawtill4 (since march this year). I eat amounts like a horse (and also take similar dumps). my energy levels are through the roof. I can work with more clients than ever. I haven’t had a coffee (or any other stimulant) in 6 months. I didn’t drink any wine, beer or any other alcoholic beverage in the last 15 months. Sleep is normal, I still need 8-10 hours per day. Nothing changed there. Just getting up in the morning got a whole lot easier and joyful. Skin got better overall, and muscles seem to look more aligned and in the right place – my physique changed considerably, without any change in workout amount or type.

  73. Hi Tim,

    I enjoy your stuff and your experiments, especially the ones about nutrition and performance.

    I really do wonder your opinions about the training method “High-intensity Interval Training”. If you would make a blog post about this thing,that would be awesome…Thanks

  74. I have been in ketosis for a while now and although it was hard to train at first, once the adaption came it actually increased my performance. I do MMA which most people will tell you is impossible without carbs- I don’t know how my body is doing it, but my body seems to work better and is still able to do explosive stuff. What I will say is that since being in ketosis, I don’t have the same desire to just do “crazy workouts” if they don’t have a meaning. I think when a person has carbs they have some sort of physical desire to burn them out. I have much more sensitivity to overtraining now in the sense that I am more aware of it, whereas before I could not see it until it was too late. Aside from training- no fatigue in life full stop, balanced emotionally, mentally strong and stable energy all day are some of the benefits I have had.

  75. I love the theoretical advantages of Ketosis. BUT, in reality, the anecdotal effects that ketosis has on adrenal and (therefore) thyroid health is difficult to ignore, even in those who do not calorie restrict. There are no population that survives in ketosis long term. Even the inuits, often held up to be the bastion of nutritional ketosis, get decent quantities of carbs from roots, berries and the glycogen in the sea mammals they eat.

    Keep the ketosis posts coming though, I’d love to hear more.

  76. I have been following a strict ketogenic diet for the past five years with no negative side effects.

    I chose this lifestyle for several reasons :

    – I am narcoleptic and eating carbs seem to aggravate my condition. A bowl of pasta makes me fall asleep;

    – if I eat carbs I gain weight right away; my face tends to become fat before the rest of my body… It’s also the part of the body

    Lost 27 kilos the first year from 98kg (6ft2). Before ( ) [pink tie] and after picture ( )

    I rarely do any cheat days… and when I do I feel bloated, sick and sleepy.

    1. I did a very low carb diet for a couple of years. However I recently transitioned out of it for health reasons. When I tried adding carbs back in I got the same symptoms as you: “bloated, sick and sleepy”. This is not a sign that carbs are the devil but simply that you’re body is not used to them. It always amazes me that people are happy to accept low carb flu but not the flu that comes with the reintroduction of carbs. It took at least 2-3 weeks before I could eat carbs without feeling bad. Now, a few months down the line, I can eat a whole sweet potato and feel no bad effects at all.

    2. Anthony: I am just like you, the same thing happens if I eat a normal high carbohydrates diet. I don’t understand how can some skinny people out there eat pizzas, pancakes and yet remain so thin. That doesn’t happejn to me. If i eat pancakes, breads, pizzas and potatoes my face gets bloated.

  77. Can anyone in this feed give me their thoughts on total carbs vs. net carbs? From what I understand, the net carb camp says to subtract the grams of fiber from the total because fiber has virtually no impact on blood sugar. Is that actually the case?

    1. What you basically need to do is check yourself because I have found personally that at the beginning of me going ketogenic, I had to keep veggies really low to let my body get adapted to fat but after a while I can pretty much eat as much as I like of the green ones and mushrooms etc without any problems. I think its just a case of giving your body the clear signal that fat is the fuel and not carbs and once that is established it seems to relax a bit.

  78. Hi, i am not a nutrionist expert, a ketogenic expert, but I wrote 3 diets, they are a boring and repetitive, but not too expensive. They are similar to the warrior diet, however I included breakfast in them:


    Breakfast 3 eggs, 4 egg whites, 2 tablespoon of butter (450 calories). 35 fat grams

    Lunch (0 calories).

    Dinner # at 8PM 1: 14 ounces of cooked chicken, 12 ounces of iceberg-lettuce (800 calories). 40 fat grams

    Dinner 2: 11 PM: 3 eggs, 4 egg whites, 2 tablespoon of butter (450 calories). 35 fat grams

    Total calories: 1700 calories

    Percentage of fat calories: 58% fat calories


    Breakfast 3 eggs, 4 egg whites, 2 1/2 tablespoon of butter (500 calories). 40 fat grams

    Lunch (0 calories).

    Dinner # at 8PM 1: 14 ounces of cooked chicken, 12 ounces of iceberg-lettuce (800 calories). 40 fat grams

    Dinner 2: 11 PM: 3 eggs, 4 egg whites, 2 1/2 tablespoons of butter (500 calories). 40 fat grams

    Total calories: 1800 calories

    Percentage of fat calories: 60% fat calories


    Breakfast 4 eggs, 4 egg whites, 2 1/2 tablespoon of butter (600 calories). 45 fat grams

    Lunch (0 calories).

    Dinner # at 8PM 1: 14 ounces of cooked chicken, 12 ounces of iceberg-lettuce (800 calories). 40 fat grams

    Dinner 2: 11 PM: 4 eggs, 4 egg whites, 2 1/2 tablespoon of butter (600 calories). 45fat grams

    Total calories: 2000 calories

    Percentage of fat calories: 58% fat calories


    Breakfast 4 eggs, 4 egg whites, 2 1/2 tablespoon of butter (600 calories). 45 fat grams

    Lunch (0 calories).

    Dinner # at 8PM 1: 14 ounces of cooked chicken, 12 ounces of iceberg-lettuce (800 calories). 40 fat grams

    Dinner 2: 11 PM: 4 eggs, 4 egg whites, 2 1/2 tablespoon of butter (600 calories). 45 fat grams

    Snack between meals: 3 ounces of cheese (300 calories, 27 grams of fat)

    Total calories: 2300 calories

    Percentage of fat calories: 61% fat calories

  79. I have been experimenting with keto all of 2015. I lost 20 lbs of body fat so far. There was a big learning curve and a lot of hacks to figure out what really works.

    Keto and ketogains sub reddits really helped a ton.

    After your interview with poliquin I am trying to do straight keto for 60 days to get down below 10% body fat before getting back on a CKD.

    I feel the biggest hurled is getting in enough fat calories. I train powerlifting and strongman. Getting 160g of fat a day makes a world of difference but it’s a lot of work

  80. I have switched to a more body building/IIFYM diet since about April. I noticed the first comment on this thread back in 2013 mentioned Mark Smelly Bell using a ketogenic diet. I thought that was interesting just because I am a big fan of his and Super Training. Mark used a ketogenic diet at the time because he felt it would help him get rid of some bad habits. He says that ideally the best diet is a body building style diet, which he currently is doing.

    At around the age of 26, my metabolism took a turn into the shitter. Prior to that I had some difficulty keeping weight on and could just about eat anything. It was pretty easy for me to get to and maintain an athletic physique. After putting on about 45 pounds over about 6 or 7 months, I came across the Paleo/Primal diet, and dove into a more ketogenic diet. I lost 30 pounds fairly quickly. The nice thing that happened with that diet is that I cut out all of the cookies, ice cream, pastries and cake that I had been gorging on. I lost the 30 pounds; I weight trained 4 days a week. However, I kept a layer of fat on my midsection that never went away (after two years of strict adherence). Eventually I started moving away from a strict adherence to “being Paleo.” About a year ago I put on about 25-30 pounds. I got up to 242 pounds, the heaviest I have ever been in my life (I am now 32). I felt like shit and I looked like shit. I had given up on watching what I ate and I was sedentary. I would make excuses for not going to the gym. Around this past December, I bought a squat rack, a barbell, a bench, and some weights and put them in my garage. This eliminated excuses like “I don’t have time to get to the gym” and “I don’t have any clean gym clothes.” I started following Wendler’s 5/3/1 program.

    Around this past March I decided to get serious about my diet as I was still very much tubby and I didn’t want to spend money to replace clothes that no longer fit me. Luckily, I came across a youtube video of Dr. Mike Israetel being interviewed by Chad Wesley Smith (who is a SHW power lifter who has the 10th highest all time raw total). Mike went through a list of supplements that had no evidence of benefit in the scientific literature, and then gave 5 supplements that actually had conclusive evidence. The thing I liked is that he explained how to go about evaluating research. He talked about how 1 study finding 1 conclusion is nice, but it really doesn’t mean much. It means it needs further study. He said it’s best to look at meta-analyses of the literature of a particular subject when evaluating efficacy.

    This is getting longer than I intended (that’s what she said). The reason this article interested me was because of the title Ketosis and Athletic Performance. Why that is interesting to me is due to Dr. Israetel (his Ph.D is in sport physiology, saying that the scientific literature is very clear about carbohydrate intake and sport performance. If you are an athlete and you want peak performance, you need to eat carbs, and you need to eat a lot of them. Dr. Israetel was the head sport nutrition consultant at the US Olympic training site in east Tennessee (in addition to previously being a high level power-lifter, who can do this: He has transitioned to body building and he does nutrition consulting with body builders, power lifters like Chad Wesley Smith and Cross Fit athletes such as Colleen Fotsch. He also sells diet templates for anyone that is looking to either cut fat or bulk. What I really like about his approach is that he is not selling a magic trick. If you want to cut fat, you have to #1 get your daily caloric intake in order and #2 get your macros in order. He has other things added in like nutrient timing, food composition and supplementation (which is last on his list of priorities).

    So I started tracking my calories and eating foods that matched prescribed macros as outlined in my personalized template in April. The goal was to lose 1-2lbs a week, and another goal for me personally was not to lose any strength gains I had made. This isn’t a miracle story and its an ongoing process. The fat didn’t instantly melt off my body. Over time though, I have seen a pretty dramatic reduction of fat on my body. I weighed 219 pounds this morning. That’s 23 pounds I’ve lost over 4 months, which isn’t a sexy number, but it is exactly what I was looking for. These are the types of foods I eat: lean ground buffalo, low fat swiss cheese, chicken breast strips, pita wraps, eggs, veggies, lean steak, white rice, potatoes, sandwiches, fruit, cottage cheese. I supplement with dextrose/gatorade + whey intra-workout, and casein. On days I train I get about 220g protein 300g carbs and about 55g fat. On days I don’t train I get about 220g protein 120g carbs and 80-90g fat. I have about 5 meals a day (a protein shake counts as a meal). I have maintained strength gains and would say I have even gained a little. It’s foolish to say that I have gained muscle though on a calorie deficit, as Dr. Israetel says that “lean gains” are essentially a myth (unless you are a beginner, or are on the trenbolio train), however, the diet has mitigated any dreaded catabolism.

    I think it’s important to realize that there is no magic pill for fat loss and for the vast majority of people, it comes down to calories in vs calories out. This is coming from someone that bought into the Mark Sisson Primal program and the works of Gary Taubes for years. Start tracking what you eat. Did you lose weight? No? Reduce calories. This is exactly what Mark Bell says as well, to bring it full circle.

  81. Hi Tim,

    Love your new podcast! It is an awesome listen in the car and I really enjoy that you put so much effort into creating great content, as well as keeping some strong minded people within the perimeters of your interview 🙂

    I stayed on a ketogenic diet for about 2 years. I kept to under 25g of carbs daily and 75-ish% fat. It worked well for me with regard to weight loss and energy levels, but I lost some muscle and ultimately gained back about 15 of the 30 lbs that I had lost. It’s a great, efficient diet but very difficult to maintain long term. My biggest troubles were muscle and strength gain and ultimately what turned into a binge eating disorder. I had about a 6-day strong and 1-day binge cycle. The binge ended up becoming bigger and bigger until I had to stop keto all together and try to develop a better relationship with food. Now, I feel I do best with a high protein, moderate fat, low carb diet (50g) that works well with my composition and for my sport (CrossFit). Let me know if you have any questions!

  82. I’ve used cyclical ketosis combined with intermittent fasting for the past 2 years. The first noticeable characteristic is consistent higher energy levels and the ability to think more clearly through more of the day. I stopped working out for the last year and maintained a visible six pack and muscle definition, I did not measure but also did not notice an increase in body fat. I spent the past two months in Spain on a typical diet of beer, bread and potatoes and noticed immediate brain fog, fatigue, difficulty sleeping, and an increase in body fat. It was totally worth it, of course.

    Ketosis and especially internmittent fasting don’t work for everyone. I have a Native American genetic background and do well with keto and IF. My girlfriend has an Arabic genetic background and had a horrible time with IF (which is probably more from gender than phenotypes) and can lose fat and feel better with a moderate clean carb intake than a high fat diet. Test and find out what works for you, regardless, check your pulse immediately, 30 minutes and 90 minutes after eating to find out what foods your body doesn’t want and remove them from your diet. That’s the easiest and best start to improving your diet to feel and perform better.

  83. I love ketosis because if your body has gotten used to 8 mile runs, and you can’t drop anymore body fat, you can go down to 20 min interval training and lose 14lbs in 21 days… I just did it. A metabolism that uses fat for fuel is a beautiful thing. (BTW, for those of you who are about to say all I lost was water, not so. I hyper-hydrated and still was 10 lbs lighter than 21 days prior. These were the “last” 10lbs, from 189 to 175 at 6′ tall)