Will the Ketogenic Diet Make you Faster? The Science of Low Carb High Fat

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The studies I used in this video:

[Tubercyclosis]

I know this is all anecdotal, but here's my experience with keto:


I stayed on a strict ketogenic diet for 5 months while working through a training plan I'd done once before on the bicycle. All my numbers went down significantly. My 20-minute FTP test power dropped almost 10%, but my actual FTP (full 1-hour power) probably dropped more than that because my ability to hold power at or near threshold also decreased. My heart rate went up dramatically for a given power level. I could do long Z2 rides without getting hungry or eating anything, but my Z2 was significantly lower than before the keto diet. VO2 max intervals were almost impossible. Finally, the joy of riding and training was gone; it felt like a chore.


I stayed strict on the diet for five months and never saw an improvement. I know of several other cyclists who've tried keto and had similar results. I know of nobody who has had any improvement of any kind (performance-wise) on keto. The only advantage I realized was that I lost about 8 pounds, and it stayed off after I abandoned the keto diet.

[PedroGringo]

As an older humanoid, I'm too programmed to think fat is bad to consider a high fat diet. I can imagine how that conversation with my health care professional would go. It is cool that there's science diving into that. Thanks for educating!!! I learn something new every time I watch one of these! Keep it up!

[crazywallawalla]

I appreciate your honesty and research into this topic. The keto diet was a very effective weight loss tool for me. I shredded 20 lbs in a couple months training for a triathlon, so I would recommend it, but it takes a lot of discipline. Now I cycle on and off the diet, so it works for me, but it sounds like the diet is becoming a 'fad' or discredited by many people. I think what's important is that the diet steers people away from highly processed foods (sugars and carbs) and toward eating natural sources (fresh meat and vegetables). With companies selling products and recipes, this keto 'buzz' is missing the point of eating this non-processed diet.

[b-manz]

I'm wary of studies around keto because often they are not done right with adaptation timing. Just giving people high fat and then sending them out for a run will not be a fair test. Back in the 90's tests were done and found no difference in a speed. Power is usually lower on keto however for anything 3 hours and above it has huge benefits around eating timing.

[davids]

Dylan Great video. I tried a Keto Diet last year about this time to drop weight and train before the BWR. By the way would would crush that race. So training was ruff. Lack of energy. Definitely a lack of max effort out put. training was a chore mid ride. Never seemed to be well fed. always seemed to want to stop for fat and protein. However 20 lbs weight loss. so how did the ride go. Well right to gels and carb drinks. I knew I needed it. The loss of weight really helped but the wall came. I was able to fend it off a bit but this year no keto for me. Extra lbs. or not better training will make it even better. Sorry, added this comment to Ashley's by accident.

[ofirlan]

What about doing keto for the of season and high carb low fat for training and for race season would it be optimal ???

[AlbertoIaniro]

I'm starting keto diet for wheight loss 5-6 kg that I've build during winter. But it's true that I'm tired. I'm starting with a scepecialist doctor. when I have reached the desired weight coming back to more carbs diet

[barisbolat]

Dude great channel, please upgrade the mic if you didn’t already

[hunters]

Hi Dylan
I’m a masters cyclist, done keto for a year. What I’ve learnt by testing ketones by blood test is that prior to a ride I can be in ketosis and above 140 heart rate approx I go out of ketosis and the body uses glucose....fight or flight as they say.
Eliminating basic carbs and sugar is clearly a healthy way to eat but for and intense training we run on carbs and ideally complex carbs. Keep up the good work👌🚴

[baggerdave]

It is funny. Just today a MD who has a focus on longevity, sent out an email that compared these kinds of debates to religious and political debates. I also listened to a Joe Rogan podcast with a vegan Dr debating a whole foods practitioner. Anyway, what I got out of it was the 90% + overlap of the two diets. If you eat whole healthy foods, stay away from processed crap (except during races) and live the rest of your life in a healthy way, low alcohol consumption, good sleep, low stress, physical activity, and otherwise healthy habits, you will get benefits from either. Entering into a religious debate that is masked in science is probably not helpful to anyone. People get lost in the BS. This happens with politics, religion and other topics. Sadly we can recognize when people are talking about politics or religion, but can't recognize that this debate has taken on similar characteristics.

[smharley]

Is there any new science regarding ketone esters like HVMN, and if they're beneficial on 'race day'? Both in performance and in amount of additional food intake needed. Thinking about using it for unsupported 12-24hr FKT-like attempts where you have to carry all of your nutrition and would be constantly taking in carbs to keep glycogen levels high. On the pricey side to just experiment with...

[jamesd]

i think most of the studies miss the point, and that the athletes should use high carb diets in and during the races, but have benefits from their time of increaseing fat oxidation during the high fat phase

[daisydela]

Another great video. I really appreciate you going over the science and studies. Its best to have a healthy dose of skepticism with any diet since it’s a multi-billion dollar industry. So many fad diets come and go, with charismatic “experts” extolling their virtues with slick marketing.

[aarondcmedia]

I lost 30kg (66lbs) in 12 months on keto (104-74kg), so it was good in that regard. Coffee for breakfast, bacon + salami and eggs for breakfast post-ride, salami + cheese + nuts for mid-ride eating doesn't get much tastier. But yeah, your intensity is going to suffer and thus your power for hard efforts doesn't quite ever get there.


I've lost 7kg (80-73kg) over the last 10 weeks (injury, etc and life in general meant I went back up to 84kg a few months later after losing all that weight) through solid training + intensity and carbs. My power is creeping up as my weight creeps down.


I wouldn't knock keto, but for a racing cyclist you want to develop carb adaption / utilisation for the intense stuff, no question.

[z]

You ignore medical mafia conspiracy while discussing these “studies”. You just cannot eat any high fat or whatever and claim it to be ketogenic. You got to be fasted after high fat to be considered in ketosis.

I always cycle fasted and on low keto diet. I find it best for endurance and for power you got to be on keto for at least a year.

What happens is when you go keto then glycogen stores reduces because you are consuming high fats… but glucose is always required esp for fact actions… so after getting fat adapted body again adapts to natural glycogen levels. And that takes about 6 months to 1 year.

So someone on keto must wait for about a year to see high intensity gain. Endurance gain will be immediate after 36-72 hours fast.. you must fast these lengths to be truly fat adapted.

I am again stressing on endurance…. And post about a year you can get into power gain as good as any carb addicts. Yes, I sailed carb addicts because all carbs are addictive. And medical mafia loves carb addicts because it wrecks health.

[fastleopard]

Thanks for some insight into the science behind a diet fad

[kentmoore]

Keto diet worked great for me until O got back on my bike. Bonked every ride. I get fat on carbs however I can still go on long rides.

[AK-kyxg]

My performance levels, recovery and health shot up when I removed all animal products from my diet. The biggest thing I noticed was the ability to ride at short intense levels without usual significant lactate response. It must be whole food tho. Junk food plant-based isn’t gonna make you a better athlete.