LCHF/Keto diet - effect on training/performance

Nutrition
86

Never tracked macros before, but definitely high in carbs, but I also didn’t try to avoid fat per-se. I rarely ate breakfast. Lunch would be something like a sub from subway or jimmy johns, no chips, but a sugar-sweetened beverage. Dinner was usually homecooked, by me: a protein, a starch, and a veg. I like cooking, and got pretty good at it.

Now I’m keto. Lots of meat and some added fat, with a low-carb veg like broccoli or brussels sprouts. I still don’t track, but weight has been trivial to maintain. Pretty much no starchy/sugary-carbs except for some special occasions. Certain HIIT or long long duration sweetspot workouts (I’m thinking TR build phases or century rides) get in-workout gatorade, but this pretty rare (I leave myself a note about it in my workout comments for future consideration).

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87

I’d have to disagree. I don’t think you can always determine the intensity just based on the time. Otherwise I could say “flat-out” is only the intensity you can maintain for a 100m sprint. Can you hold that for 1 hour? What speed/intensity is the 1hr effort? Is that only tempo? I myself race Tri’s and thats about 2:15 efforts, and those are flat-out, almost 100% Zone 5 HR, which is definitely above tempo for me. Everyones ability to endure above threshold is different, just like everyones aerobic and anaerobic gates are different. All of which can be trained to improve.

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88

Two years ago I was 89kgs. At age 35 and 5’6, definitely obese. I didn’t think I was obese because i always compared myself to others - there is always someone bigger than you!! That was my excuse. When i complained about my weight, i would hear things like “you have lots of muscle under there or big boned or its just water” no. it was FAT!! With 6 kids, i decided that my health is very important. I want the live for a long time.

In the past, I have always been active, running, basketball and weight lifting but never had a six pack. I have dieted, lost weight only to put it back on. Yo-yo.

It was time for a change. Jan 2018 I decided i would ride to work - every day without fail. By May 2018, i weighed 75kgs. Lost 14kgs. But my diet had improved but not changed. Got fitter, ate more cake…my weight started creeping up. i rode more and more…by July 2018 i was almost 80kgs. Something had to change.

We had a weight loss challenge a work. This was the motivation i needed. That’s when i discovered keto and intermittent fasting 16/8. I won the challenge at 66kgs in 12 wks. I have never been 66kgs in my entire adult life. I think the last time i was 16yrs old. AND my six pack finally showed up. My kids loved it. The love fit dad…

At 66kgs, i felt fatigued. No energy. I knew this was not the right weight for me. A month later, i went back 70kgs. Felt great!! I had a dexa scan, had 10% body fat and 62kgs of lean muscle…Happy days. Since then,my weight has remained between 70 - 74kgs. The main change for this has been adopting a keto/low low carb diet.

These days, i just don’t get hungry or think about food. I have days when i eat higher carbs for workouts but never higher than 100g - 150g. My average day is less than 50g - net carbs. Feel great. Look awesome.

The other benefits, i have become sensitive with my body especially how different foods affect me. For example, when i eat cabbage, broccoli and cashew nuts, i get inflammation bloating for days. In the past i never realized this. I just though i was eating too much…

In terms of performance, I joined TR around Aug 2018. Not racing, just wanted to get faster. FTP was 185. By Jan 2019 FTP had increased to 250. Had an accident in Feb which took me off the bike until June. FTP back up to 250. haven’t been structured in my training - family / work - but working to improve. Goal 4w/k…280 - 290 FTP

I have noticed that on longer rides, I dont need to eat. Some days SS and threshold efforts are hard - after maybe 45mins. This is when i might supplement. They are hard anyway!!

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89

Congrats, thats a great story. Thanks for sharing all the details. I’m glad you found your happy/healthy place.

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91

So a 6hr effort can be “all out” but a 4.5hr effort cannot? Or just the slow 200m “sprint” at the end turns the 6hr effort into an “all out”? Confused at what exactly you’re getting at? :man_shrugging:

95

Why not quell all the assumptions and speculation and contact the racer in question and ask him what he meant by “all out”? :+1:

[edit: recent “flat out” Tweet by said athlete: https://mobile.twitter.com/petejjacobs/status/1175354019146977280?ref_src=twsrc^tfw|twcamp^tweetembed|twterm^1175354019146977280&ref_url=https%3A%2F%2Fpublish.twitter.com%2F%3Fquery%3Dhttps%253A%252F%252Ftwitter.com%252Fpetejjacobs%252Fstatus%252F1175354019146977280%26widget%3DTweet ]

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96

“flat out” is a relative term. I can go flat out on zero carbs and flat out fully carbed. But the wattages of both are different. Flat out is more of an RPE thing.

So not sure why we are arguing about how the guy said he felt. If he says he went flat out, that means he couldn’t go any harder in those circumstances.

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98

I’m not sure why you have issue with the 2nd part you bolded. The body does have mechanisms to produce forms of glucose from fat. Training will increase this ability. He never states that this happens at a rate fast enough to sustain short high intensity efforts.

I’m not arguing HC vs LC. I actually ride HC for 75% of the year. I just feel that this issue is so polarized that both sides often miss benefits of both because they already made up their mind.

100

Well to be fair that is the whole reason and title of the post

101

Can you elaborate? The chart from the respective study indicates the same glycogen usage:

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https://www.sciencedirect.com/science/article/pii/S0026049515003340#f0010

103

Hah, I was just looking at the fat-ox/cho-ox chart and trying to figure out how to square it with the mmol/kg of glycogen that were burned chart. I think a key realization here is that in HC athletes the liver is full of glycogen as well, whereas LC athlete is getting no contribution from liver glycogen.

Another view of fat-ox in LC athletes is this diagram.
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The peak fat-ox is shifted pretty far to the right, but drops substantially more precipitously after you exceed it. The FASTER study says the running intensity was 64% VO2max, well past the HC fat-max, but still under LC fat-max.

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104

Yes, sure, but you were saying LCHF athletes don’t use much glycogen. The study shows the opposite, they burn exactly as much as the HC athletes. Which is sort of surprising given all this talk about glycogen sparing when on LCHF.

106

But in the Noakes study they only used less glycogen because their pool was much smaller at the start of the exercise. They still used up everything that was availbale (to a level equal to the 'Mixed" group post-exercise which appears to be the lowest you can empty this pool). Hence, nice confirmation of the results in the FASTER study: no glycogen sparing, no matter what a fat oxidation machine you are

grafik

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108

I am a type 1 diabetic so I started on the Keto diet in April of 2015. That’s how I started it.

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109

Have you stuck with it? Seems like a really good reason for that dietary change. How do you feel about it in regards to performance?

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110

What’s a “snowflake experience”? Apologies in advance, I’m English.

111

Yeah - I’ve been keto or LCHF for about as long as I’ve been riding a bike. Got my first road bike July 2015.

Regarding performance, I can’t say that I really feel anything different. I’ll have the occasional bad workout and wonder if it’s due to fueling, and honestly it probably is, but I also have plenty workouts where I have no issue.

Truthfully I found this thread because I had a bad V02 workout and was wondering if it’s because of this. However I eat a ton of fats and proteins that I know get converted into glycogen (because I can see my blood sugar rise) so I’m not sold that’s the reason.

If I had aspirations of being a national champion maybe I’d change my diet, but my goal right now is to place top 10 in a Cat 4 race this year, and I’ll be starting as Cat 5. I think that can be done with my diet.

Tl;dr I like it, I haven’t noticed any difference in my training but truthfully it could be because I don’t know any different.

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112

Snowflakes are unique. There are no two alike.

We are snowflakes. What works for you may not work for me.

However, want to lose weight? Low carb seems to work for a lot of people.

Want to go fast?

Um… lose weight first! :upside_down_face:

113

Low carb would probably work for everyone in terms of losing weight. But mostly because in the short term it’s mostly easy and fast water loss.

Fat loss is more about input control and work output, regardless of what diet/lifestyle you’re following.

114

Ah, CICO… the paradigm is quite pervasive. I think in 50 years they’ll be laughing about how astray nutrition went chasing calories. The right answer is to address hormones.

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