Ketogenic Diets Suck for Speed and Power
More data just in case you needed it as a brand new study has found some shocking conclusions (1).
They took 16 young men and women, and tested them over 4 days under:
1) a low carb condition of less than 50 grams per day and
2) a high carb diet at 6 -10 grams / kg/ day aka- carb jackpot!
The exercise testing was Wingates on a bike and the yo-yo test. For Wingates -think of pedaling really fast, and then all of sudden some evil lab nerd drops the hammer on you by upping the resistance massively! Within about 10 -20 seconds, it feels like your quads were replaced with concrete. And no, the yo-yo test was not playing with yo-yos – it is an intermittent sprinting test.
The low carb keto group saw their power drop by 7% on Wingate test in addition to running 15% shorter distance on the yo yo test (1).
I can feel the keto krowd getting ready to pounce and cry.
“But these athletes were not keto adapted!”
To which I would agree, but how long do athletes need to be keto adapted?
Last I heard, the timeline keeps getting longer from a few weeks to a few months, now to a couple years. I do agree that the chronic adaptations are different and may be beneficial; however, ketones for a bioenergetic standpoint cannot create ATP (cellular fuel) at a fast enough rate to compete with carbohydrates. Plus we have metric piss-tons of data (techy terms) that carbs enhance performance. Read these and weep, keto power posers (2-23).
Keep in mind that while your keto athletes are working their way through keto flu and adapting to the keto diet, based on this study and other data (24-28), they are losing speed and power!
There better be one hell of a payoff at the end of that keto power loss train to make up for the lost training time.
Maybe the keto approach is ok for very long duration athletes; but we can debate that one later.
In the meantime, I am going to have some carbZ to keep my power up both in myself and the athletes I coach.
Summary- Too Long, Did Not Read
Newsflash – removing the main fuel for anaerobic exercise (high intensity) is not good for performance.
If a power drop of 7% does not matter to you, keto until your eyeballs turn yellow as butter.
But if speed and power matter to you, carbZ are your friend.
Pass me the poptarts.
PS- I did NOT say “keto sucks for everything,” just that it is not great for high intensity work.
Keto Power Poo Poo References
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