The Problem With GCN's Take on the Ketogenic Diet

GCN just released a three part video series on the ketogenic diet to further muddy the waters on the optimal diet for cycling. Today we dive into the science to get to the bottom of the question: will going keto improve your performance and help you lose weight?
GCN's videos:
Part 1: • High Carb Vs Keto Diet...
Part 2: • What Happens If You Ri...
Part 3: • Is The Keto Diet Worth...
Keto for weight loss: • Are Ketogenic Diets Be...
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Studies I used in this video:
www.researchga...
jandonline.org...
link.springer....
psycnet.apa.or...
physoc.onlinel...
www.mdpi.com/2...
www.tandfonlin...
link.springer....
pubmed.ncbi.nl...
pubmed.ncbi.nl...

[@DylanJohnsonCycling]

Hyper Gain Beast Mode Mass Gainer KETO Edition is now available in butter flavor.

[@HarryTzianakisTheGodOfSpeed]

🤣

[@jetBlue_83]

Holding out for the bacon flavor too

[@4headgaming448]

this is the content we need

[@JibbaJabber]

Hot Diggity 🐕!!! Just the thought of it has made me constipated💩 Oh look, I've just dropped 10lbs of water weight💦 Put me down for couple of supersized Ghee tubs!

[@future62]

Looks like Backwards Cap Dylan got your password bro

[@mrdudemanmwane8963]

It’s absolutely shocking how small Dylan’s channel is. He deserves 5 million subs

[@imterribee]

I agree! I get way more value out of his videos than I do from all other athletes I subscribe to combined.

[@JibbaJabber]

That's because he tells people the truth, which can be a downer, boring and everybody hates a know-it-all. Go Dylan👍👍👍💪💪💪💪

[@assaultedpeanut9]

Well subscription count doesn't correlate to quality/ entertainment value (which are subjective)

[@vfgjasminebaker]

Yea like wot

[@joomzb]

Yes! Wish there was more making use of the real science that has been done rather than 'muddying the waters'

[@Dutchandstuff]

It's smart though; if you get all your competitors to go keto you're guaranteed a win!

[@statixsc3013]

... ur a messiah.

[@evadeproductions4255]

Also have nobody fast to ride with

[@danielweiss]

My thoughts exactly :D

[@garyrussell9706]

LOL

[@ortizma13]

Except the fact that team Sky (now Ineos) used and uses ketones to improve performance and they have won many times

[@alexande94]

So refreshing to see you rely on skepticism, critical thinking and actual scientific evidence to base your beliefs on. This is my favorite cycling-related channel at this point.

[@shauryakaushal7145]

The video actually has a lot of misleading scientific references which are cherry picked for convenience of argument. Check this out kzbin.info/www/bejne/aXmZZZ2ArbembJI

[@williamwightman8409]

@@shauryakaushal7145 I have to agree with you after scanning each study. Dylan did not spend enough time learning the topic before making this video.

[@lagelkrow7575]

"This kid thinks he is the next durianrider..." Priceless! 😂

[@bernardlinde]

That was priceless indeed! 🤣🤣🤣

[@tonycrabtree3416]

Disc brakes cause covid... LOL

[@paulojrg]

@@tonycrabtree3416 Fact! Prior to disk brakes there was no Covid.

[@roebbiej]

Lol that guy is so nutty its becoming funny

[@edwardo123]

"disc brakes on road bikes causing covid" literally made me lol! also always appreciate the constant study after study info on these videos rather than biased opinion.

[@NikoxD93]

he's biased though and finding a few studies that confirm your bias isn't hard to do

[@pieterjordaan4220]

Ive been on a Keto Diet for 5 years due to my T2 Diabetes, Lost 30KG in the first 2 years till I reached my goad weight, lost a few more KG's since then and have been cycling all this time, My LBM hasnt only increased slightly but atleast it hasnt dropped. I am 49 Years old and not aiming to win any races but I can do a 100km ride with no food, also don't feel like falling over after the ride, during my longer rides or events I have some standard muesli bars that I eat for a bit of energy so not always sticking to just low carb during events. I do agree Keto is not for everyone, if your body doesn't like carbs then try keto, if you are already performing well on carbs and dont have problems with carbs, why bother switching? They say not all diets are equal but maybe that is wrong, maybe all diets are equal when matched to the right person. I bet some people will even perform well on a MacDonalds only diet ;)

[@mtnbikehead]

Yep, genetic heritage determines what the body prefers for nutrients. Anyway, a 4 week study is bullshit. 20 weeks plus there is steady performance improvements. Dylan never touches on oxidative stress cause by carbs. My first race after going low carb took 40 min off a flat race that took me 5 hours prior. Previous races I mentally crashed after. I felt great after the first low carb race. No sugar hangover. Recovery is so much faster.

[@zavman109]

Two years for me, same

[@Tortriroy]

Low carb coming up 4 years feeling stronger and am more muscular than ever at 54 yrs old. I went this way due to a standard athletic high carb fueling messing up my system. My longest, fasted ride is 150km, with no bonking, happy with that. Am I racing, nope, I will not go back to carb fueling.

[@DublinDapper]

@@Tortriroy Eating fat... genius 🤡

[@theshastafarian]

@Han Boetes Bollocks

[@andrejkiss]

Backwardshat Dylan is such a well created character :D. I always laugh at his comments :D.

[@future62]

Regular Dylan is actually the character. Backwards Hat Dylan is the real person

[@paulantosh5501]

@@future62 This makes sense in 2020.

[@andrejkiss]

@@future62 Then may I suggest a new name for the character: Forwardhat Dylan.

[@lechprotean]

needs a spin off series

[@vivoslibertos]

Next episode EPOgenic diet with back hat Dylan.

[@HarryTzianakisTheGodOfSpeed]

😂🤣😆

[@Martindilg]

Lol. It will be interesting 😀

[@HumaneNewt]

Know an expert on that diet. Think his name is Lance..

[@vivoslibertos]

@@HumaneNewt '... But I never tested positive'

[@DougTheSnowMan]

Was Jeremy on a keto diet or just snorting a ton of coke?

[@HarryTzianakisTheGodOfSpeed]

Both

[@billinhouston3291]

That dude is drug free, but is sooooo hyper.

[@SmolSnake]

I met him in person last year and it turns out this bubbly, hype-beast persona is not a performance.

[@umaxi96]

The problem with most studies is that the transition periods are way too short! Even 4 weeks for adaptation before any performance tests might not be enough. Many studies however don't respect the transition period!

[@HarryTzianakisTheGodOfSpeed]

No one is looking to transition . This is about cycling not gender 😐

[@HarryTzianakisTheGodOfSpeed]

@Brainjock 😂😆🤣👍

[@landerhendrickx3522]

They have been trying for years to find a spin on keto to show it improves performance. Use it as a tool to deal with hunger, cravings or weight management, not for performance. Strongerbyscience host E. Trexler has a good take on keto and has tried it for a very long time himself, long enough to get fat adapted.

[@landerhendrickx3522]

82Goors so going through a period of 7-10 weeks of restriction and decreased performance with a glimmer of hope that it will have a slight benefit in very specific situations. Can you share some studies or case studies where they had 10 week to adapt before they assessed performance metrics?

[@landerhendrickx3522]

82Goors yeah I’ve come across these names, probably 3 of the 6 most legit names you can mention. Virta is a whole new medical care setup and they stand to gain a lot of money from it so they are not as unbiased as you may think. Dylan is sponsored that’s a fair point to make. I’ll watch the video later and look into the studies mentioned in it.

[@AnnetteLG]

I’ve been keto for the most part of three years but finally added IF the last year and it’s remarkable how good I feel. I love riding in a fasted state.

[@CarnivoreDMD]

I completely agree! I’ve been KetoVore since 2019 & when I’m in my 48h per week FAST, I seemingly have unlimited endurance @70-80% AFTER the 1st 24h (I do bike @1h in the 1st 24h)

[@joseph.inglis]

As somebody who is 100% totally keto, i completely disagree, On my keto diet I've lost 5 kilos of water weight, all my friends and my appetite. My diet is the pinnacle of sports nutrition and i will not be told otherwise by any professional or scientific study as everyone who disagrees with me is being paid out by the carbohydrate industry.

[@JibbaJabber]

Yea, but you smell like a skunk's crack, and when you do eventually drop a dookie, it comes out like a block of lard.

[@mutleyadamsracing2684]

@Gabriel Batistuta Goal carbs are 1/3 macros you loser. It's not a nutrient. Carbs are sugar. Our cells require sugar to live. The brain requires sugar to function. Male sperm requires carbs(sugar) to exist. Educate yourself on the ill effects of keto damage the liver and thyroid receive because of legit keto lifestyles. Saying you're a keto athlete means strictly NO carbs. 99% of you losers eat carbs and lie about it lol.

[@iamrandom1912]

There's some explanation here: kzbin.info/www/bejne/aXmZZZ2ArbembJI

[@Bayo106]

@@mutleyadamsracing2684 low carbers have lost their common sense. That's why they talk so much shite and only shit 3 times a week at most

[@MarlowWhere]

Big Carb. I knew it.

[@andrew66769]

Top 10 signs that God is real Number 1: Dylan made a video responding to this.

[@andypcguy1]

I dropped from 230lbs to 160lbs on Keto and overall performance most certainly improved. Some people can probably handle more carbs than others. I've been this way for over two years and their's no way I'll ever go back. Bread, cakes, pasta etc. that doesn't even look like food to me anymore. My morning 27mi cycling commute today, avg speed 21.2mph on a standard drop bar carbon bike, avg hr 157, spent a good deal of of time in zone three this morning, was running late. Could I go faster on carbs, maybe, but at this point my performance is pretty decent and I'm able to maintain a good body comp and my blood work is perfect. Everything improved with this way of eating.

[@TDZed]

I gave Keto a try (cause my partner wanted to lose weight). We bought the KETO recipe books, some pretty delicious stuff too, and did the diet properly. Never again, I lost weight and fitness, I was constantly tired. Now I can't get enough carbs, my FTP is higher than ever, I have so much energy. Just eat well & balanced, stick to the good carbs too. Oatmeal is my BF.

[@arachnophilia427]

i've tried it twice. first attempts was a disaster. zero weight-loss, dark circles under my eyes, lower energy, weakness going uphill, but lots of endurance. this time, significant weight-loss, almost no drawbacks, but still noticeably weaker.

[@rosbifle413]

Oatmeal is great only it makes my farts absolutely rancid.

[@Markhypnosis1]

Did you actually give your body a chance to become fat adapted?

[@TDZed]

@@Markhypnosis1 we stopped after 1 month. So prob not? Maybe because I changed by diet and not my exercise routine I did not give my body a chance to build fat reserves...? thus why I was always tired. A colleague of mine did Keto, lost a ton of weight and felt great, he was happy, but he also was not active person (thus why he was overweight). I've never had weight issues, I'm lucky that way, and I also ride a lot (15hrs per week avg), so I need constant calorie intake, thus why KETO is prob not suited for me. I think KETO is too extreme for most cyclists. We def need to eat lots of healthy fats (which I do! nuts, avocado, full fat yogurt, etc) but also need lots of good carbs (rice, oats, whole-grains, etc).

[@Markhypnosis1]

@@TDZed I would think that the time it takes for the body to become fat adapted is dependant on how much one relies on carbs, and the type of carbs. If the body is so used to using carbs and being topped up all the time, then it will have a hard time adjusting and switching to fat burning when no carbs are available. Cyclists who are constantly refuelling on the go with high GI carbs will find it difficult. That's where the "bonk" comes in.....which is essentially hypoglycemia. It's definitely not good for the body to reach that stage as it could be a sign of insulin resistance....and I'd worry that eating so many carbs will eventually lead to insulin resistance. Not to mention the inflammatory nature of grains. I'm my experience with cutting out grains, sugar and starchy carbs, along with intermittent fasting and prolonged 2 day fasting....my body has become so fat adapted that I can cylce at 80% max effort for over an hour.....after not having eaten a single thing for 24 hours, then do a 50% max effort ride for an hour the next day after on the 40th hour of the fast.....with no lack of energy. If I can do that with no food for 24 - 48 hours, then I'm sure I could go on for hours if I'd eaten a good fatty protein and veg rich meal. It has taken time to get to that point, a good 6 months of intermittent and prolonged fasting and cutting out the above mentioned carbs types. I'm not full keto by the way, but I have cut out all grains and related food, all starchy carbs like potatoes, and sugary food. All my 3000 calories a day come from protein, fat, lots of veg, and some fruit.

[@henkegiaretta]

Have they speeded Jeremys talk up? He talks like a Duracell-rabbit...

[@RunninBird]

Yeah a lot of the clips are sped up a bit, probably to fit a specific duration. Sounds like he's on the TV commercial fine print reader diet.

[@BlackWaterCyclist]

I was thinking the micro-machine guy from my youth. 🤣

[@imabittooawsome]

@@RunninBird i reckon it's more likely they are sped up so the youtube algorithm doesn't pick up he's copied bits of gcn's video so as to avoid getting demonetised. That's why he also added music in the background of the bits he copied

[@SLACKWATERCOWBOYS]

Jeremy ALWAYS talks that fast and that much and, he often refers to himself in the 3rd person in converstion. He is a super positive , excited, fast thinking guy. He an is uncontrollably out gojng , friendly and welcoming guy and it has all paid off for him in his racing career, charity and rider development work (just ask Anthony or Stephen) and his broadcasting endeavors. Timmy J , J Pow, TreeFarm, Paige, the crown 👑 jewels of American Cyclocross.

[@CHIMPOaGOGO]

@@imabittooawsome That makes sense. I've been wondering if GCN had been coming out with videos they've done last year.

[@waynesmith4589]

GCN talk shite i'm afraid , just a big advertising platform .

[@kristiannilsson1893]

I gotta say that I love what you do Dylan! When ever you "attack" some other channel or training platforms like Zwift it never feels like you are fishing for views, just that you want to set the record straight and come at it humbly presenting the science. The closer in time you critique a video the better since someone like me can get the correct information before some less researched video settles in to my memory as referencial truth.

[@kristiannilsson1893]

@82Goors I would actually challenge you on that. State your sources and make sure that sources are reliable and I will read them. If you are just a keto-fan presenting facts that support your view I won't spend the time. @DylanJohnson actually does and you can be sure he would be full keto if it had enough scientific evidence.

[@kristiannilsson1893]

@82Goors I will try to find the study. I'm looking forward to reading. But still, Dylan does have a sports science background as well as being an elit athlete. Nothing wrong with how he went about it, but more and different studies can absolutely change what is fact. I will read and get back to you.

[@kristiannilsson1893]

@82Goors don't call me out as that partial before I have even read the study you are referring to. My comment is 5 months old. I don't even really remember the content of the video. I will read what you proposed, watch Dylan's video again, maybe even get his comment on it to see if he has even seen that study and then get back to you. I want to have the correct info no matter where it is from. I can't really say anything more on this before I update my information. Write you later.

[@dusanmal]

Couple of missing points from a scientist interested in Keto-like diets: 1)A lot of research and published work is done by completely mis-applying Keto diet. This also gives wrong idea to the general public and bicyclists... Example: Paper you used to show lower performance based its results on 4 week long "keto" diet vs carbs. After 4 weeks of introduction into Keto dieting one is lucky to even show proper ketosis. But, proper research is hard as you must maintain (in my opinion) subjects on at least months if not years in this metabolism. So, don't expect to switch to Keto metabolism in weeks or see any results in weeks. Months and years is timescale. 2)A lot of cycling-talk is about manipulating your metabolism to-and-fro Keto during the year. There another rarely mentioned fact hits: Going back or forth between carb metabolism and keto metabolism is when the stress on the body systems happen, particularly liver and kidneys. Hence, use old Yoda saying - do it or do it not. Do not plan on switching, do not even think of "cheating", if you can't stand it - quit fast, if you want it - plan on years of strict keto dieting... or you will not only hurt your performance but you can inflict serious damage to your body. Not from keto itself but from switching and/or cheating metabolic stresses. For me -I am on it since 2002, when properly applied it works.

[@williamwightman8409]

I agree generally but my experience after ten years in is that I can ride on carbs or fasted for up to 100 miles before re-feeding or rest and that my body will now adapt to what is available without a power drop. It is much easier to just eat healthy meats and vegetables to both ride strong and live long then to add in carbs which are not essential to the diet. Carbohydrate consumption is a seductive metabolic trap leading to premature ageing.

[@kvegasdirtrider1420]

I dropped 60 pounds on keto over 6 months while mountain biking about 1300 miles. My cycling performance vastly improved - duh - Thats a lot less weight to pull uphill. Felt great and did some 30 plus mile single track rides with hardly any food or carbs. Am currently trying to find a balance and enjoy carb loads before big rides. Have kept off the weight for a year and a half.

[@9P38lightning]

Forget the sugar, integrate starchy food Which turns in to glucose which is a natural sugar... Other sugars take you're body into a de Novo lipogenesis state....

[@Bayo106]

@@9P38lightning starch is sugar. Also stop with your fake science, you're wrong.

[@9P38lightning]

@@Bayo106 you tool, starchy foods such as potatoes are natural foods and the liver process those into glucose... I'm happy to help you sound challenged...

[@gpeaes]

No silly, that was all just water weight. Didn't you watch the video?!

[@aethylwulfeiii6502]

Definitely not a diet that’s going to work when your BMI is already 18.9-19.0. Then it’s just an eating disorder.

[@microwave311]

I have found that biking more was the best weight loss plan

[@ElonMuckX]

Biking up hills too!

[@MyDemon32]

@@ElonMuckX unless you're in the Netherlands :'(

[@ElonMuckX]

@@MyDemon32 Biking In The Wind Too!

[@statixsc3013]

Please dont say this.

[@ElonMuckX]

Say It Again!!!

[@bengold9312]

most what you have in this video are missconceptions 1. After the initial water loss, you loose also a lot of fat weight, indeed hunger is surpressed....i switch to 1 meal a day, just have no need. 2. keto state is very similar to fasting state but no hunger, alertness etc.. 3. No carb crush in the afternoon. 4. I am never cold. 5. I havent felt loss of performance after i understood you have to have a lot of fat and salt instinctively from all the years of fatfobia -and salt fear i avoided too much...a common mistake, this is almost ruined for me, once reversed you see the benifits. 6. Triglycerides way down, blood preaasure way down, blood sugar way down, weight way down...only first week os waterloss. 7. No cravings for sugary/ carb food, no constant food thoughts...freedom. In short, it did changed my life....I am now 10 years since my 40 birthday, I recommend, try after some good info , dont believe the "science" this is not unbiased science, 45 years they preached to avoid fat, salt etc..... it was all a huge mistake - widespread obesity is the result.

[@durianriders]

Make a video showing us eating, your blood results and your power files from strava

[@greg4318]

Anecdotal, bullshit........the science is the science whether it fits with your world view or not. You have no baseline of comparison. You would need to go back to a monitored carb rich diet where you ate properly and then compare your results. Stop drinking the keto Kool Aid!

[@jw5764]

You slow on the bike tho

[@greg4318]

Gabriel Batistuta Goal your an idiot

[@bengold9312]

@@jw5764 might be some loss, i am not competing...i am 50, 4kids.....there are more important goals in life, i feel better, it os life changing

[@RiouPlasticSurgery]

Thx Dylan, as a Physician I spend a lot a time talking patients out of the Keto Diet, often with resistance. There is a lot of misinformation out there based on anecdotal reports instead of true science. Your science-based arguments are correct and followers should listen to your advice. Besides the issue of short term performance, there is also the issue of long term good health, which is not in favor of low carb, high fat diets, particularly high animal fat diets which increase the rates of both Coronary artery disease and Cancer. Well Done clarifying the issue!

[@umaxi96]

jp riou Physicians are experts on diets as we all know because they learn so much about nutrition at university and they can really evaluate study design and general problems with nutrition science. WHAT A JOKE!

[@umaxi96]

jp riou Modern nutrition science indicates that low carb diets can reduce inflammation, control blood sugar levels etc. There is no strong causal evidence i know of how high fat diets lead to more coronary artery disease and cancer. The studies indicating that high fat diets lead to higher all cause mortality are mainly from the 20th century so completely outdated and of empirical study design. This means high fat diets are often associated with higher death rates but guess what?: They are not the cause. There are so many problems with everything in nutrition science. They can’t even decide what a high fat diet is. 40% of calories coming from fat? 30%? 70?% In the recent decade people eat less and less fat and we have a higher rate of „nutrition related“ diseases than ever from what i know... So it seems like there is something not quite right or is it?

[@umaxi96]

The best long term study on health and the ketogenic diet might be a 10+ year study of kids with epilepsy. They had/have to follow the diet strictly.

[@RiouPlasticSurgery]

@@umaxi96 you are right there is insufficient nutrition training in Medical School. It's been a personal interest as an athlete, so I make it a point to research the data in peer reviewed scientific journals beyond the normal scope of a physician. Dr Greger nutritionfacts.org/ I think is a good source of entirely science based nutritional advice by a physician. I agree one should avoid added sugars, refined high carbohydrate processes food, but most blue zones in the world where population exceed normal longevity by decades are with high non processed carbohydrate (whole plant) and low animal protein as a percentage of their diet. There is no disputing these facts.

[@umaxi96]

jp riou I was on the Dr Gregor wagon myself for a long time... The populations eating a low fat low protein plant based diet have a much healthier lifestyle in general most of the time or in some studies these people just haven‘t the same 24/7 accessibility of foods we have (unvoluntary fasting periods) etc. I don‘t trust Mr. Gregor anymore since he is trying very hard to prove his point and in some cases i found out misinterpreted the studies presented completly when i was looking at the whole study myself... Greger certainly has some good videos and points but it is a one sided discussion on his websites in my opinion... All studies on health and diet are very vulnerable to systematic mistakes and i think because of that we should at least make the effort to try understand flaws of studies, bias and different outcomes. Personally i don‘t trust Mr. Gregor anymore. He makes a lot of money selling his plant based philosophy... i don‘t think it would be in his interest to report anything positive on high animal product/high fat diets.

[@db613]

Jeremy also didn't get faster, he got lighter than he did weaker for 5 minute power, so his W/KG went up, but had he lost weight without losing power he would have been even faster for longer! So he should have called it "losing weight makes you faster" and it's not because of Keto diet rather in spite of it.

[@gilleek2]

Easier said than done losing weight without losing power though. He didn't look like he had a whole pile of weight to lose either.

[@db613]

@@gilleek2 I hear that, but any diet can work for that. I stopped eating all day at work besides for a few bowls of Kashi GO protein added raisins and drink a lot, and lost just as much weight with power gains...just saying

[@gilleek2]

@@db613 true. As long as you can stick to it. As with training, consistency is king so if you have a diet you can consistently stick to you'll shed pounds. I think some folk find it easier to consistently stick to a keto diet than other types of diet. Whether that's a food preferences thing or a physiological thing I don't know. Personally, I've followed low carb diet (so not as extreme as keto) for competing in Ironman triathlons and had great results. Didnt need to take in as many gels in a race and as a result fewer GI issues on the run where you're toying with jumping behind a bush to, ahem, do your business.

[@williamwightman8409]

@@gilleek2 Kevin it does indeed work. Also as you age you won't end up in the diabetes, heart disease, and alzheimer's trap many of these carb lovers fall into after lowering their exercise levels but continuing to eat carbage.

[@rayhradek3294]

Excellent presentation big guy! Spent many hours using the research to dissuade friends and family from using ketogenic diet to improve their performance. Much applause!

[@williamwightman8409]

Ray, in this case you demonstrate "knowledge, but not wisdom or understanding". There is also the overwhelming cognitive bias aspect here. Amazing.

[@jeandevilliers1935]

Hey Ray. Sounds great! Please list all the research that includes an adequate adaptation period, and also which specific element of performance your friends/family were successfully dissuaded from improving..?

[@omerxx]

Great video, but the last 20 sarcastic seconds reveal a massive bias against the approach. Objectivity is important to viewers (I'd like to think). Performance is not everything, there's health benefits of not consuming sugar, gaining excess body fat and others. This is coming from someone who doesn't follow the diet (I did try it for a year). Just looking for honest, non-biased experiments like GCN's. And another note, both GCN and the other trials mentioned have all tried Keto / Vegan diets or others for short periods only, none of them went through months, surly not years to determine one way or the other. And lastly, the human body doesn't have one size fits all nutrition approach. That's quite a medical consensus, some may benefit from eliminating meat while others from relying on fat. Sugars though, are non-essential for everyone...

[@jimdou4617]

Dylan, From my perspective, there is no problem with GCN's take on Keto as it was very balanced, with the intent to inform, no bias or agenda. There is a huge amount of supporting studies that demonstrate the positive effects of keto but you didn't cover those. And to the contrary there is a tremendous amount of data that shows the metabolic related diseases that are associated with high carb intake such as arthritis, heart disease, diabetes, Alzheimer’s, etc. What's important is that each should employ was is best for them. You have a good channel that I have enjoyed watching on many occasions relating to training, Thank you very much!

[@zwamman]

Please list those studies and try to keep it performance-specific. Viewers of this channel tend to be in very good health and are not in any risk groups for those diseases. Sadly, GCN has a very clear agenda: get clicks and place products. Increasing the former will raise the net income of the latter.

[@willyolio9590]

if people understand metabolism, especially during exercise, it's obvious keto diets do nothing for performance. Fat burning requires a ton of oxygen intake. Fine for when you're sitting on the couch doing nothing, and your lungs can easily handle the oxygen load. Maybe it might improve fat burning on super-casual bike rides. But nothing above that. When you work hard, keto diet or not, you're switching to burning carbs. For performance, the maximum sustained power output your body can produce will always be from 100% maximum oxygen intake going towards burning carbs.

[@prestachuck2867]

willyolio Truth Bomb. BOOM!

[@salad_gold_rancher]

The comment about cholesterol was irresponsible. Did I miss the part of the video where you proved that Keto causes high cholesterol? Don't get me wrong, pizza is my favorite food, followed by french fries. I think Keto is "too good to be true". But I am asking in the interest of intellectual honesty.

[@leecoleman450]

I actually slammed GCN about promoting this diet when they released their part one of the series. I actually got a reply from Jeremy arguing against me. Then in part two, they put out this huge disclaimer hahah So glad people are jumping on them too

[@future62]

There's only so much content about cycling that can be created. Keto is a hot SEO buzzword so they're going for clicks

[@leecoleman450]

future62 Yeah man, Chris Pritchard said the other day, that when he worked at GCN, they’d search for the ‘most searched’ topics and make videos on that. I understand the want to create popular content, but the first GCN Video was really irresponsible with a lot that Jeremy was saying. Especially as there’s a ton of research stating the negative impact on your carbohydrate receptiveness after a period of time. Trainer Road have released multiple videos on the subject and smashed it every time

[@simedinson984]

@@leecoleman450 yea there is a reson i am unsubed from GCN now days

[@future62]

@@leecoleman450 It seems to me like GCN got too big to sustain itself. Small channels like this seem to do better in the long run, as they don't need to constantly chase the metrics to survive. They have put themselves into a death spiral.

[@randell247]

I could only stomach Part 1, "maybe it's even better for you. I don't know!" ...and I'm done.

[@HarryTzianakisTheGodOfSpeed]

GCN is not to be trusted. Eating fat for high performance is the dumbest thing I've heard.

[@saynotothegreatreset]

Its like fill a F1 car with diesel . It never will perform the same ever again

[@HarryTzianakisTheGodOfSpeed]

I totally Agree guys! 👍

[@marcdaniels9079]

Yup. Agree !

[@jasonmccartney4167]

In 2018 Dr Dan Plews broke the long-standing age group World Record in Ironman Kona on a low carb high fat (LCHF) diet, also beating 90% of the pros. Let me be clear, it's definitely not Keto, there are still some carbs mixed in, but it's still using fat as the primary source of fuel. There are many high performance Ironman athletes on LCHF diets. Fat for high performance is the dumbest thing you have heard? That comment is up there with the most misinformed things I've heard.

[@ketoriders7531]

@@jasonmccartney4167 I've coached many athletes on a keto diet and never seen any bad results from it, neither on high intensity performance nor endurance. When you are adapted, just as you say, you can use strategic carbs to optimize performance and recovery. If you start a race in ketosis and take in carbs during the race, you are not going to go out of ketosis as you have other patways to get glucose into cells when AMPK is activated from the activity. You are not going to trigger large amounts of insulin in that case. The amount of carbs needed seem to be individual so everyone have to experiment. If anyone comes to a final conclusion through the available science, they are going to be wrong. There is not science available to come to a complete understanding, but when we look at the mechanistics of metabolism paired with real world studies, we can get a pretty good picture, and it's surely not a negative one.

[@aitoraltuna]

The durinarider mention had to be there

[@Savantjazzcollective]

I thought this was obvious? Why would low fat athletes use ketosis to compete? they don't have the fat stores! Keto is for getting through winter time when food is scarce after putting on weight in the summer. your last statement in regards to Keto good or bad was way off here. If somebody feels fantastic on keto, by your logic they should give it up because your balance of evidence doesnt agree. There are statistical outliers in every field of study and there are many, many pro's for the keto regime, you are being very biased in your conclusions and assumptions

[@rwt31111]

BRAVO! Well done and thank you for that video!!!! Anyone who has read Endurance Diet by Matt Fitzgerald will know that exactly what you said here is the TRUTH! He looked at the BEST endurance athletes in the WORLD (the Kenyan marathoners) and what it was that they ate. Also took into consideration the same studies that you likely looked at. Either way... BRAVO!

[@guilujan]

I am stop following GCN videos, they r becoming repetitive and like this one from Jeremy, pretty bad in content. Keep the good work Dylan... cheers

[@danielandersson3539]

A bit much product placement now. It's developing into a commercial channel. Thanks to having Discovery for an owner I suppose.

[@heikkisanelma6625]

Dude, you should be bit more careful what sources to use. Categorize the studies used, I.e. Hawley and Lacley study is for sports "lasting "up to 3 hours"... more modern take on the subject of conserving the cho for ultra distance events up to 10hr or more is not to go keto, but to have low enough Bla to ahve meaningful impact on entsyme and hormonal signaling to add bang for the buck for the adaptations from workouts to build up the cell metabolism etc. and to stress less the gut on the race day with less intake of cho during stressfull exercise ti minimize GI problems... It should not be news to anyone that carbs are the primary fuel, but for different events and sports you have different limitations... All I'm saying you work here just the same way as Powers works on his 3 part series on Keto... you want to believe there is only one truth :) Im not advocate for keto, not at all, one should be very careful threading waters in that realm, but for health and performance in my sport, of long distance triathlon, strategic low carb approach with planned execution is very good way to boost those adaptations and race performance...Dylan i enjoy your content, bur hope you wont turn a blind eye. Even published papers have their flaws and limitations, biases even... carry on the good work!

[@HarryTzianakisTheGodOfSpeed]

all studies are wrong the studies are based on ketones that are already stored as fat in your body, not ketones that you consume on-spot energy. Ha ha ha Only thing your body can process and give you energy on the spot is carbs. The fat your body stores from carbs is used later on as ketone processed by your liver. You can better access these ketones in a fasted state. I can do 100 mile ride and not even eat in the morning. First my body he uses all the energy from the food I ate the night before. Then when it's done with that energy it Taps into my fat Reserve using ketones as energy this can only be accessed through religious fasting. When you eat anything that is fatty it makes you lazy and you just want to roll get up and go to bed. But when you eat anything high carb it gives you energy. I bet you think the Earth is flat

[@heikkisanelma6625]

Keep open mind folks. That's what I'm saying. And if u guys deny the role of carbs I.e. Cardiovascular and metabolic disease.. Not even trained athletes are free from that stress complitely. Diverse your fuel sources and aim to be fit AND healthy.

[@alexanderSydneyOz]

"All I'm saying you work here just the same way as Powers works on his 3 part series on Keto... you want to believe there is only one truth :)" I must say, that is definitely not how it came across to me.

[@umaxi96]

Alexander Stollznow To me it did.

[@heikkisanelma6625]

@@alexanderSydneyOz okay. Not related and pointing anyone particular, but the theme mostly. Nutrition is such emotionally loaded topiz thst it's very hard to get good conversation around it.

[@marvin123o]

Dude, I died at "this internet video and the two podcast I listened...." XD

[@tylerfountain1286]

most of these studies are to short in nature as it takes 4 to 12 weeks to become fat adapted on the keto diet. Also the liver converts glycerol from fat into sugar as well as amino acids and lactate into sugar so carbs aren't truly necessary. it takes a while for the body to produce new mitochondria that burn ketones but the brain works 70% better on Ketones than glucose and ketones act like an antioxidant to protect nerves and tissue break down. there needs to be tests that take into account the scientific knowledge in it's entirety and not these quick converts who look to dismantle a metabolic state that we've had for millennia. bottom line is we need accurate info and accrual studies based on science but big pharma doesn't pay for nutrition info and there's no money to be made in a capitalist healthcare system.

[@PoorAttentionSpan]

YES! I completely agree. Regrettably, I think Dylan did a quick Google Scholar search, found articles, among many, that supported his beliefs, and went with it (I felt a twinge of irony when he was talking about the placebo effect). I, personally, think the waters are still pretty muddy...Dylan did very little to clear them up.

[@adrianjoachim5819]

The studies cited are very short term studies (despite the title telling otherwise). What is often overlooked (also here) is that the goal is not "ketosis" as state (easy, a bit intermittent fasting and a low carb meal and I'm there in two days). The goal is fat adaption! That takes at least 12 weeks. And of course, if you have athletes fat adapted for month - and then give them carbs for a week - they now have both fuel sources. Of course you will see increased performance for a couple of weeks. That's basically what Chris Froome did. No one believed he could win the Tour on a LC diet for preparation. But he did.

[@denvergriffin5555]

In any "study" that compares the outcomes on Exposure A to Exposure B or no exposure, there tend to be positive responders, nonresponders, and negative responders. The "results" are basically the average of all outcomes in each group. (It is the same with, for example, polarized versus nonpolarized training.) Letting the overall results become some maxim or universal principle for you is an assumption that your response will match the average response. If you want to know the effect ON YOU - you have to try it and see. I'm quite sure that the parade of horribles here - though they may manifest "on average" did not occur in my case - after 9 months of VLC, I had 35 lbs of essentially effortless weight loss (and no, it most assuredly was not all or even to any significant degree "water weight"), no flattening of performance improvement after the first 2-3 weeks of getting used to it, and the best lab values, including cholesterol levels, of my life. I don't think those were influenced by the placebo effect. Eat what you want; but if you want to know what effect this or that has on YOU, you have to try it and see.

[@Dmlsej]

This comment is excellent! My experience is very similar, and your point about people responding very differently, is very important!

[@williamwightman8409]

Yes, spot on.

[@BillyBob-nk8ib]

Where is the Hyper Gain Beast Mode Merch!?

[@tgoods5049]

Cupcake flavor 💪🏽

[@mathieubrisebois9341]

Hey Dylan! Love the channel, I study exercice science and I am helping on a couple of research papers. At around 9:30 you cite a study that has people go keto 6 Days and then test performance with carbs, but the guy in the previous video suggests we need a month to adapt. Therefore I think it does not respond to that question of longer term low carb and then periodizing carb intake with workout intensities. That being said, I do realize that running that study would be a logistical nightmare. Also I think the video could have benefitted from clarifying Keto vs low carb, because I believe you cite studies that use both and they can be very different. Still, I agree that science is clear that Keto is not good for performance in general. Low carb, especially periodized could be though.

[@suisinghoraceho2403]

You are right about the experiential setup does not address the question. However, if your ability to use carb is already compromised after 6 Days to the point that a carb load wouldn’t matter, it is only going to get worse after a longer period in Ketogenic. Though I agree it will be great if Dylan can delve deeper into how to periodise carb properly.

[@mathieubrisebois9341]

@@suisinghoraceho2403 not sure how you get to if...in 6 Days...gets worse after more time. That is just your opinion, not a fact.

[@vilgotlindh9701]

The month to adapt is not scientifically proven. They have shown similar rates of fat metabolism with 6 days of adaptation and therefore they used that timespan.

[@mikehardwicke23]

I agree. Keto is tough too. Lowcarb plus OMAD for me!

[@mathieubrisebois9341]

@@vilgotlindh9701 would love to see that study comparing 6 Days vs 30 Days. Unfortunately, until you share that link, it does remain an opinion.

[@bhatch]

Love the channel for your clear-eyed and no-nonsense approach! Legit question: is there a Dylan for runners? I know a lot of the studies Dylan cites are about endurance athletes in general, but in terms of how the research translates into structuring training, is there someone (maybe at CTS?) that does a similar thing for runners? Asking as an athlete who likes cross-training on the bike, but is primarily concerned with racing on foot and is tired of the seemingly endless list of streamers that provide advice based on their own experience without referencing actual research and data to back it up.

[@skasseCG]

Cherry picked studies and quotes - most of which are a decade out of date. Low - carb is not keto. Cholestoral comment cast bias into the entire video. About the only thing you got right is the hit on high-end performance. You've said in multiple videos that the only thing you lose is water weight - that is short sighted and the weight comes back on keto during adaptation. Also - adaptation period for seasoned athletes who have bodies tuned for carbs will naturally take much much longer to adapt to another energy source than a few short weeks. I expected much more from this video, but am leaving disappointed.

[@valentinofogarty9943]

The GCN guy didn't do a proper keto diet so it was all a waste of time personally. His ketone levels were not high enough, 1 was his highest but he needs to be in the 2-3 range, it also takes months to be fat adapted.

[@marcelchaloupka]

I’m rarely below 2 but the other side of the coin which isn’t talked about of generally understood it the relationship between keto leaves and insulin as spiked insulin lints the effect of keto. The objective is to have low insulin levels and high Keaton levels. There as a basic calculation, blood glucose divided by Keton level. Anything less than 3 means you’re properly in ketosis.

[@fyimediaworld]

I have yet to see a proper study done on ketogenic dietary adaptation. The idea that you can feed some fat for a few days or two weeks to an athlete who has eaten carbs all their life then measure an accurate performance is beyond idiotic. That time is exactly the time period where adaptation begins, and performance does drop during that time. No proper long term studies have been done yet. Your video here only adds to the pile of garbage science interpretations on this topic. And the idea that a if lot of people either do or don't do a thing makes it the right thing is also laughable. Call me when a large properly controlled year long study supports the silliness being spread around about this topic. Until then let's call all this what it really is ... Junk science.

[@umaxi96]

Frank Illes I completely agree with you. Look up „Effects of a 12-week very low carbohydrate high fat diet on maximal aerobic capacity, high intensity intermittent exercise, and cardiac autonomic regulation: non randomized parallel-group study“ (Randomization with studies on nutrition is not possible). Here the athletes are keto-adapted and can endure very high intensity trainings without any extra carbs consumed.

[@MarlowWhere]

Dylan does say in the beginning of the video that there is not really any conclusive evidence either way because of the limited studies . He goes on to say the studies that are out there dont really do much to prove its efficacy over a balanced carb diet for athletes.

[@fyimediaworld]

@@MarlowWhere ya, I watched the video, and I know what he said and when he said it.

[@josedasilvaroque4564]

I have a simple rule: eat when you are hungry and remove processed food from your diet. So after hard session, you will have to eat more carbs to balance out the depletion. Your body is smart enough to let you know what it needs, so you will figure it out. Good video. Thx for putting up the studies.

[@lightningslim]

Keto is responsible for me getting back on a bike after 20 years of illness and bikelesssness. The "Research" ocean is full of "Research" funded by the "Carbohydrate Industrial Complex" there are a lot of investors in the food industry. Oh, and I lost 57lbs "Water weight."

[@tiagoreis9934]

Backhat Dylan is a f*****g legend! King of sylogisms and inductions!

[@aaroiseverything]

Thanks!! was waiting for this!!!

[@guglio7350]

Backwards Hat Dylan is the most straight forward way to nail the concept!! Keto = the gain of not eating gels while riding...brilliant haha!!

[@RonGoote]

I'm down 180 lbs on keto. Elite athletes often sacrifice long term health for short term gains. This is why they become t2 diabetics and have heart problems shortly after they retires. That insulin resistance will hit and your health will go down hill.

[@geanbrum4202]

Hey Dylan. Awesome content. As a triathlete I hear a lot about the low carb approach (keto adaptation for a few weeks - 2~5), where you eat something between 100/150 grams of carbs/day. Dr. Dan Plews (Amateur Ironman marathon world record in Kona holder) has a lot of researches and studies about it and he's a great defender of this approach. I'm very curious on your thoughts about it. Thank you!

[@durianriders]

Plews claims he did 8:24 in ketosis.... TOTAL BOLLICKS! I challenged him to a race where we test his ketones and he blocked me. 😂

[@mathieubrisebois9341]

@@durianriders so why is it bull...?

[@geanbrum4202]

@@durianriders So, as long as I know he wasn't in ketosis (and he hasn't been for a while), but in a paleo low carb diet. According to his philosophy, you just have a certain period of time in full keto (

[@ketoriders7531]

@@geanbrum4202 That's exactly where the discussion is. Use keto as a tool to optimize metabolism and then use carbs strategically. I myself do full keto days and extra carbs after my hard sessions. It seems like different periodizations works best for different people so everyone has to experiment a bit. I have coached people that perform and feel best in constant ketosis to (not elite athletes). It depends on many things. One thing i know for sure, you are not going to find the best diet for everyone through the science, and I'm not sure such a diet even exists.

[@marcelchaloupka]

durianrider talking rubbish as usual

[@Witty..UserName]

Study of n=1 (myself) My cycling performance is HEAVILY weighted to the Keto/Fasted state. Before the GCN vids, I posted often on the GCN channel about cycling 100miles at intensity in the front range/foothills of Colorado completely fasted. At the time I was tied for 4th on a sprint section attempted by over 7k riders on strava. All of that & I could bench over 200 & deadlift over 400. In my 40s. I haven't ridden in a year due to stopping a truck with my bike/body, but before that I was on a not-so keto diet & my performance was down. Next season I will be back on the bike & be 100% keto w/IF as well. I ride my bike faster on fat & ketones while on an empty stomach.

[@watermydriedupsoul]

I have to disagree with the "water weight" thing though. I guess it worked differently for me since I'm far from an elite-level cyclist and was 100kg at the start of keto. I lost 15 kg and gained back only 5kg after going back to a normal, carb-based diet. I'm now steady at 90 kgs (with muscles). So I guess, for my case it wasn't pure water weight that I lost. Only a low portion of it.

[@jeandevilliers1935]

Hey Dylan Lots going on in here! I am not being defensive of Keto. Just the hasty method used to dismiss it. For your opening response to the GCN Powers test.. simply shouting ‘Heisenberg’ and pointing out that motivation can increase with the introduction of a new training variable gives no evidence that this was case. ‘Jeremy looked motivated’ doesn’t count. You’d either have to apply it consistently, and rubbish all pubmed articles that don't employ complex deceit mechanisms (so probably most of your screenshots here along with all the carb studies, low cadence studies, weight training studies, etc that you cite across all your videos)… or you can concede that we have no evidence in this particular case and call it what it is.. just an n of 1 and we can consider it as an additional datapoint nonetheless. RE: all the articles that you cite with a 4 week adaptation and test phases where Ketogenic was inconclusive/poor.. not sure if you’ve ever tried keto, but I have. I had to get fetched from a looooot of pavements long after 4 weeks still. Turns out when you spend say 30 years eating one way (10k+ days), it takes more than 28 days to adapt to something completely different. This should not be surprising or controversial. I’d call anything after 3 months adaptation fair. Problem is that there’s just not a whole lot of that in the literature that you will find in your searchbar. Data scarcity is the issue. Then asking professional cycling teams what they’re doing to enhance performance hasn’t cut mustard for the last 30 years, and it’s certainly not any kind of credible scientific method to be mixed in with pubmed. RE: Net negative, a top line article count says nothing of quality. Better to go by what specific question was being asked, and what the method was. Forgetting the premise, the added ability to ride fasted is pretty useful for cyclists if.. say, you bounce a bottle in a race or don’t like spending $$$ on sports nutrition? (Funny anecdotes here on the FASTER study when tests were delayed and the high carb group was climbing a wall). Or what about being metabolically flexible.. so a keto athlete can always pick up a bottle at an aid station (down regulation claims aside), but a carb-dependent athlete has nowhere to go. Or the fact that less bottles and bars on a bike just plain weighs less and makes for a more simple nutrition plan? I hear that bike weight is a big thing for cyclists. Or gut distress during races from not having to slug down 150g of carbs an hour? Or just day-to-day being able to skip breakfast. I found that quite handy. Each individual can weigh them up and figure out what is important to them. But the benefits aren’t zero, and it’s not quite open and shut. Probably more, but I’ll leave it there for now. If you are interested, I have repeated test results of myself conducted by a sports science / university lab over a period of a couple of months with strict protocols. I’m not keto anymore, but I was adapted for a couple of years at that point so they’re valid in this context. The lab & testers went into a lot of this stuff around down-regulation, and repeated testing across multiple durations from sprints to 100km time trials in the lab. Some of the findings were quite interesting, and some were very counter-intuitive.. some fly in the face of that third GCN video.. but they are what the are - Just another n of 1 to add to the pile for consideration. Happy to share the white paper, if you like..? Just found your channel. Enjoying it. Keep up the good work! Tx, Jean

[@mtnbikehead]

Sorry Dylan, I think you missing some of the evidence. Jeremy may have had some placebo effect; probably. But the one thing that You even pointed it out. fat oxidation prolongs muscle glycogen and less bonking. Beyond 3 hours, those that are more fat adapted really start to shine.Events under 2 hours are not really endurance events in the grand scheme when there are so many ultra marathons and triathlons that take several hours. I am not Keto albeit for several weeks when activity levels are low. Carbs are saved for higher intensity days. Staying metabolically flexible is key. Dylan is missing the decreased inflammation which improves recovery. Carbs, especially simple sugars and gluten are responsible for the byproducts of oxidation that are inflammatory. Water weight from inflammation does not help performance. Fat oxidation results in water being released and is usable. I can honestly attest that I can ride longer and faster with less water and rarely feel dehydrated after, whereas before I would have to drink large amounts of water after and would gain water weight after long rides. Keto, low carb and fasting is fantastic for decreased inflammation, and better metabolic health. It took me 14 weeks to get back to where I was before, performance wise. Another 12 weeks to really improve performance that had plateaued and declining despite lots of training. Now my FTP along with w/kg are the highest they ever have been, along with v02 max about 40% higher than when I was carb addicted. My 2 KOMs come at the end of longer rides. Anyone wanting to try low carb/keto, do it in the late fall just after the end normal riding season. Genetics will determine how well you adapt to higher fat and lower carb. Its not for everyone, but it worked for me.

[@АнтонАлексеенко-р1у]

Are you saying that a person who lost 30 pounds over a course of half a year doing KETO is going to regain all the 30 back in a matter of weeks because it was only water? Doesn't seem to be that way. The water is lost over a course of a first days, then comes the fat itself. KETO diet is designed to burn fat after depleting the glycogen store, which stores that water. Therefore you deplete that water storage every single time you burn the glycogen during high intesity training in a same way KETO diet does. You don't gain all your weight back after reintroducing carbs. When you've lost 30 pounds and regained 2-3 pounds, even 5 after rebuilding glycogen storage it is still minus 25+ at least.

[@disgruntledtoons]

Rule #1 of research: If you methodology is s***, you won't prove anything. My laymans' suspicion is that going keto is something that you have to do slowly over time so that your body's ability to raid the fat stores for energy is built up slowly over time. Expecting to mash it after a week is probably a recipe for disappointment. My other take is that most of the benefit of the keto diet comes from eliminating excess sugar (which is horrible for everybody).

[@kimberlystewart8980]

The science of nutrition in terms of study design isn't great though. I've worked with a nutritionist for about 5-6 years now and she'll be the first one to admit that we are sometimes trying things that have a single study of 30 people for 30 days behind them. I know she generally doesn't make claims as strong as you're making. I'm surprised that such a hyper-focused topic like sports performance has enough significant, well designed studies completed around it to make firm conclusions on.

[@benanderson4639]

If you know anything about zach bitter, you know he's not human. And I think when running 100 miles like zach, keto might be more applicable.

[@RookandRule]

Scientific studies on performance changes related to ketogenic diets take athletes and change their diet for at most 4 weeks (that's the longest I have seen). I don't think this is enough time to actually adapt to the new diet and therefore actually compare the performance. For a well adapted athlete, very adapted to a given lifestyle, it might take long time before changing something as critical as the diet will allow for performance at the same level as before. You did reference a publication (at 5:40) where "fully adapted" athletes were tested: the main outcome of that work was just that they run on different a metabolism but there is no significant performance difference. Still, this doesn't mean that some of the carbo-athlets could perform better after adapting to a high fat diet or vice versa. Probably, this would be my guess, those athletes (being such) had already got pretty close to their personal optimum. I am not advocating for a ketogenic diet (and I am not even doing such a diet) but I think you should account more for the limitations of all of the studies in the field (any nutritional study). The fact that there are several papers showing something doesn't make them absolutely right. In this case there seem at least to be exceptions. To be scientific there must always be room for doubt. Anyhow always interesting and well documented videos, keep up the good work!

[@richardmiddleton7770]

Metabolic flexibility is key to endurance performance. If you are constantly fed with carbohydrates you will get through a race but you will need a ton of gels, bars etc! And you will need more and more as your body becomes resistant to insulin until your performance will actually go down no matter how much sugar you consume, by that time you're probably borderline diabetic! Once you are more fat adapted you will literally never bonk again! If you've tried keto and failed miserably it just means your body is too reliant on carbs and you need to practice more keto or fasted rides.

[@marcelchaloupka]

You’re actually wrong on the weight loss aspect of keto. You loose significant amount of fat while loosing minimal lean mass and in my case an increase on lean mass along with a increase in body water. One of the key aspects of keto unlike other methods is the metabolism does not slow down so there is no yo-yo effect. Any new diet will result in an automatic 5kg weight loss and that’s why snake oil diet program sellers can say you’ll loose 5Kg if you follow this or that diet, but get back to me what it’s 30kgs. The point you’re missing and GCN is you can’t get the performance gains nor the weight loss gains in 6 days or in the short term windows that these studies use. It takes some time and effort to get into a nutritional state of ketosis and become fat adapted. It’s a lot more complex that you are putting forward and there is more nuance to the topic. That being said if you’re a sprinter, crit racer, track cyclist, keto isn’t for you as you need explosive energy. Go do an ulta distance cycling race and keto works very well. You also touched on intermittent fasting which is what keto pros do and goes hand in hand with the keto diet. The combination of keto and intermittent fasting has a profound and beneficial effect.

[@andresromerocoz]

In general the video is well documented but I think there is a lack of papers about long term ketogenic diet in endurance athletes, because you have to take in account that the keto adaptation process is from 6 to 8 weeks. The one certain thing that I found is the decrease in peformance for high intensity work and also that athletes in ketosis uses more oxygen for getting the same amount of effort because of the fat oxidation. I have been searching a lot about keto diet in cyclists because I just get diagnosed with polycystic kidney disease, so even if for most people a high carbohydrate or mixed diet is better for performance, the keto way can be the only path for me to be a competitive cyclist and don´t destroy my kidneys in the process.

[@spinme100]

Dylan any science on performance and intermittent fasting? Currently doing 8hours eating 16 hours fasted. Do a video please

[@durianriders]

Just slows your thyroid. I've been a coach since 1996. AWAYS HAVE CARBS FOR BREAKFAST!

[@taxgladiator9093]

MJ was a big fan of Gatorade for breakfast. But again Dylan says it right, weight loss is the key component here. Best to wear a sweat suit you’ll get more water out. Didn’t any cyclist wrestle in college.

[@wvjeepguy8178]

My dad started keto around this time last year and has lost 120 pounds as well as gaining a lot of leg muscle from jogging, which is his only real excersize. I'm not saying it's for everyone, but its the first diet that ever worked for my dad.

[@erich8258]

Thanks for doing this video. I was pretty annoyed at GCN for their series -- as you say, there have been a number of real scientific studies on Keto. Jeremy Powers' anecdotal experiences don't change this, and they don't offer any meaningful new information on the subject.

[@billinhouston3291]

Oh man, the background music in that GCN video is batty.

[@ΘάνατοςΧορτοφάγος]

Bike jersey have backpockets. In said pockets you can fit gels, bars and chews. Even bananas. You can also add carbs to your bottles... Glycogen stores can run out...so eat on the bike. The keto crap needs to die.

[@brianh2771]

Unfortunately, you lost all credibility with me when you mentioned the word “Cholesterol”.

[@vegasmando5307]

*Me eating a dozen donuts during this video* Also Me: Yep, I'll be ready for the Tour de France any day now.

[@KurtMcDowellOKC]

Appreciate your review. I was extremely disappointed in GCN’s take on keto. Haven’t seen episode 3, since I was so triggered after the first two. The science is clear.

[@arachnophilia427]

i've been cycling on keto for about 8 months. i haven't been super strict about it, and carb load about once a week. most of these studies are done on pros who are already quite fit, and tend to be shorter duration. i have to wonder what they'd find starting with out of shape amateurs. anecdotally, i'm cycling way farther than i ever could before, and going much faster. i've lost about 60 lbs, which probably helps both concerns. but i can also confirm that my high intensity output is just not there like it used to be. it's pretty obvious in MTB, less so on road.

[@junpimentel5624]

The carbers are just jealous. Durianriders are just old and miserable with their weakend carb up bodies.

[@ubik111]

Awesome video as always

[@stanleycrocker775]

Excellent parsing thorough the details. Great work! Stan Crocker Registered Dietitian

[@JesseKellys]

I got a copy of Clinical Sports Nutrition by Louise Burke, which is well worth a read as it is assembled by many researcher looking at many studies. They came to your same conclusion. Struggling with weight I'd love it if a ketogenic diet worked for both weight loss and performance, but the chance that I my lesson my ability to take advantage of carbs for 'power' jaded me. Why anyone would kill off an entire food group is beyond me? Remove any of the three groups entirely and you'll lose weight; but more likely because of less calories or malnutrition! I know the ketogentic diet is still being studied and there may be some real benefits to those with various cancers or other conditions. But if you're healthy there's no reason for a ketogenic diet; (lest be your religion.)

[@JesseKellys]

physoc.onlinelibrary.wiley.com/doi/10.1113/JP278928

[@BMMB450]

Thank you Dylan for the informative vlog. Please try to Cover in future how to recover or cure from metatarsalgia issue. It is killing me man and avoide me from cycling for long distance and it is painfule like hell. Like 👍🏻

[@gte534j]

So safe to say i should keep training and racing on Trader Joe's chocolate babka? Thanks for confirming what i knew like 10 years ago.

[@MarlowWhere]

Chocolate Babka trains you

[@DennisNowland]

This is an excellent video. Years ago I tried low carbohydrate and I felt absolutely bloody crap on it.

[@emilioc700]

As always, thanks for your objectivity. Jpow must really like coffee.

[@danielpinto1417]

Great video! Putting the thruth økt there! Congrats

[@pwrteams]

Great video, point taken. Message delivered to ones who can listen. ;-)

[@gamecat1923]

Well reasoned video as ever, I don't know why some people treat keto as a religion rather than a diet with only anecdotal benefits.

[@jseski9209]

as someone who has personally benefited health-wise from a keto/carnivore diet (as well as my mom, a few other relatives & some friends) having non-diabetic tests results, reducing/controlling cancer, eliminating acid-reflux, & more ... these are far from "anecdotal benefits" in most people's books It's not a religion. It's just simply not putting shitty processed "foods" in your system. Real meat, decent real veggies. It works for some, & I completely respect it does not work for others - that's fine, I don't push it on anybody; but it's funny how many are outraged that I do...despite having massive health improvements.

[@DM-hc1nc]

When you said "peak oxidation" I thought you said "peacock sedation."

[@marcelnali]

Whew! I bonk just thinking about a low carb diet. Thanks, Dylan!

[@ts4357]

Very much enjoy the scientific approach to your videos Dylan! An unrelated question to the video. I cycle and run, both of which I would like to do competitively. Both sports individually have similar types of sessions (easy recovery, low zone rides/runs, intervals, long sessions, tempo, vo2, strength, etc). Of course, if training for both you wouldn't double up on most of these sessions (esp. high intensity). That leaves the question - which sessions should be done as rides, and which as runs? Or alternate/split? I understand that this is out of place in a cycling specific channel's video; the problem is, I am yet to find much info on multisport training structure except for tri, and I'm not interested in swimming. I would really appreciate any thoughts on this.

[@KellyVicentBBVChamp]

Ha! Literally the cholesterol comment is the only reason I chose to leave a comment. I think he got a lot of things right in his analysis but it’s a common result of doing keto that ones cholesterol levels drop, even with the increased fat intake. Presumably from decreased inflammation, etc. Overall very informative though. My experience with keto for the past year has been weight loss from 209 to 162 pounds, increase in ftp, ability to never feel overly tired on the bike, total increase in desire to train, lower BP, and decreased appetite. Results may not be typical but it has been great for me.

[@jtday1028]

How's your 5-second, 1-minute, and 3-minute power?

[@KellyVicentBBVChamp]

jtday1028 all 3 have actually increased slightly over the past year. 5 sec - 1120, 1 minute - 528, 3 minute - 323 watts

[@scotth3354]

Re: caffeine placebo effect, I think you meant subconsciously, not unconsciously. No one works harder when they’re unconscious.

[@Bayo106]

unconscious also means doing something without realizing ... for example, you unconsciously made a fool of yourself by correcting somebody that was already correct

[@gerardnc]

Performance aside, there are many middle aged individuals on the edge of (or with) type 2 diabetes or heart disease from the modern (high carb/sugar) diet and ketogenic diets have shown promising results in reversing or halting the progression of these. That said, a whole foods vegan diet has also shown the ability to reverse/halt these ailments, although both diets eliminate simple carbs and sugars (and processed vegetable/seed oils). High carbs and sugar raise insulin and this in turn elevates blood triglycerides which are a much better indicator of heart disease than cholesterol levels. Fit cyclists, however, are more efficient at converting glucose to energy so their insulin does not yo-yo like those of someone who does not exercise much, therefore their blood triglyceride levels are low. All this to say, that outside of performance, a ketogenic diet, or vegan one, as extreme as they may be, do have some health benefits, although the vegan one does not have as big a performance downside (although for health reasons, it does require supplements like B12 and DHA/EPA).

[@williamsamson2177]

Hey Dyl, thanks again for your awesome, well-researched videos. I've been arguing with a riding buddy of mine about this for a couple weeks now. One thing I think people also get wrong is that the body is not necessarily burning one fuel source at a time. Energy metabolism is an incredibly complicated and intricate topic and, from what I've experienced, many people who are pro-ketogenesis assume that during CHO-fueled training one does not burn much fat unless you're in the "fat burning zone". I think this severely underestimates and undermines the body's ability to burn multiple sources of fuel simultaneously. One thing I have been wondering about though, is the point at which you eventually run out of glycogen stores, and can't absorb energy fast enough. Let's say your body can store 2000 cal worth of glycogen, and you're consuming 90 g of carbs an hour (approx. 360 calories, right?). During a 7 hour race then, when your intensity is high, let's assume you're burning 850 calories per hour. After 6 hours you've burned approx. 5100 cal, but only been able to consume 2160 cal (assuming your body is absorbing the carbs you ingest at physiological limits). So the net loss is 940 cal, with one more hour (potentially the toughest) to go. With all this in mind the main question I have is, is your body burning fat consistently throughout the race to supplement the CHO metabolism? If so, is it known at what rate your body can provide energy from fat stores during high intensity exercise? Essentially this could give us an idea of how many calories one can burn per hour once CHO stores are depleted, and therefore an idea of how one should adjust his/her intensity to avoid hitting the wall.

[@BlackWaterCyclist]

Lol I love the cholesterol comment at the end. Carb is king. Thanks again for a great video Dylan.

[@KellyVicentBBVChamp]

Ha! Literally the cholesterol comment is the only reason I chose to leave a comment. I think he got a lot of things right in his analysis but it’s a common result of doing keto that ones cholesterol levels drop, even with the increased fat intake. Presumably from decreased inflammation, etc. Overall very informative though. My experience with keto for the past year has been weight loss from 209 to 162 pounds, increase in ftp, ability to never feel overly tired on the bike, total increase in desire to train, lower BP, and decreased appetite. Results may not be typical but it has been great for me.

[@estogaza1]

Kelly Vicent same with me here. I've been on keto for a year now. I'm not competitive cycling athlete, but I also never feel overly tired on bycycle even on long distance. But diffrent people may have diffrent result tho

[@markjthomson]

Interesting observations. One thing I would note, ANY study looking at performance UNDER 6 to 8 weeks in keto will give a reduction in performance. It takes longer than 4 weeks to adapt, making a 4 week study comparing keto to normal eating pretty meaningless in comparative results as the people in the keto group are still undergoing adaptation. Professors Phinney and Volek are looking at studies of people in ketosis for more like 6 months.

[@marcdaniels9079]

Brilliant analysis as always. Thank you for these objective fact based videos. Biking must include cake eating! Coach Greg not a fan of Ketosis either and he knows a lot of stuff !

[@nihilistmarmot]

This illustrates why I subscribe to DJ and unsubscribed from GCN a long time ago. People who ride a lot probably don't have the time and education to do science. Literature reviews are informative, but unfortunately, the goofy antics of GCN's hosts are more "entertaining" and get the eyeballs.

[@mattbond21]

Nigel “the fat nutritionist” Mitchell on the GCN video lol

[@lloydranola]

Love the shade thrown at that Duran racist! :)

[@endianAphones]

Thumb for durian bashing.

[@Mark5ive5]

I watched this GCN series skeptically and literally wondered what Dylan would say about all this. Another great video!