Ketogenic diet does not affect strength performance in elite artistic gymnasts

[José Ignacio Varela Suárez]

http://www.jissn.com/content/9/1/34

Very interesting...

[Dimitar Grozev]

I think that this has bee mentioned before.

The issue with the study is that the "strenght" tests are too easy for gymnast to count for something. Even if the diet had a negative affect that wouldn't show up when using such easy exercices as baseline tests.

[Andrew Long]

The exercises they used were just plain stupid. You probably starve a gymnast for 4 days and they could still do that stuff. That's not even a warm up for them

[José Ignacio Varela Suárez]

Yes. That is really true. Personally I tried during two weeks and I did not feel any drop in performance. However, the drills of this study are really easy for the gymnast.

[Kevin Haimann]

As long as you refill the glykogen you used, you will never feel just a hint of drop in performance. That is such a big misconcept.

The thing is, that gymnasts train like 25-35h per week, even if we say only 12-20h is hard strength work, that would still be 2-3h of hard training a day. An average man with lets say 175lbs should get 50-150g of carbohydrates if he is not sedentary, which means active lifestyle and 3 times strength training of about 1h.

From experience I would suggest for every hour of really hard working 10x3 Highbar Backsquats and 4x6-8 Romanian Deadlifts as well as some core work a 175lbs man would need 0,25 to 0,5g carbohydrates per lbs of bodyweigth depending on bodyfat level.

Now it is easyly understandable, that a ketogenic diet as defined there cannot fit any gymnast. Still the diet of that gymnast WILL be ketogenic, because carbohydrates are used during exercise and remain in musclestores. The insulin output would stay almost constant throughout the day if not too much carbohydrates are taken at once. For sure you want to start filling your stores immediatly after training, but be aware of that the intestinum may need up to 1min to take up 1g of glucose if there isnt a big drop in bloodglucoselevels...

A constant bloodglucoselevels and therefor insulinoutput promotes ketogenesis, which is why a diet of 300-400g of carbohydrates can still promote ketogenesis.

[Nigel Leeming]

Like many ketogenic or low carb tests, this was done over a 30 day period. Adaptation to a ketogenic diet takes 4-6 weeks, so it probably needed to run a bit longer.

 

I would have expected a poorer performance as many complain around this period of being weak and unfocused, especially if they don't get enough salt, so the fact that there was no degredation in performance could mean, as everyone seems to have noticed, the tests were too easy. It's amazing how much research gets done missing some fundamental points.

[Nigel Leeming]

Just read a bit more, specifically, this bit: "The percentage distribution of total energy macronutrients was 54.8% fat, 40.7% protein and 4.5% carbohydrates."

 

That's an awful lot of protein.

[Joshua Naterman]

Guys, I have dissected this thing to Kingdom Come in another thread, but I do not know where. It was a while ago, but if anyone has the link to that it would be fantastic to post here.

 

Short version: This study is absolute garbage. The methods completely invalidate all conclusions made.

 

Explanation for the above: 

 

1) The no carb diet had diuretics, stimulants, and a whole laundry list ( more than 20) of supplements added to the diet. The "Western Diet" period did not. Conditions are not equal, and therefore no drawn conclusions are in any way valid.

 

2) If you look at the trendlines for the measured variables, nearly all of them are NEGATIVE during the ketogenic portion and POSITIVE during the "Western Diet" portion. Even though the differences did not reach a level that would be considered statistically significant, there is no doubt that the performance trends were not in favor of the ketogenic diet.

 

3) Diuretics artifically reduce skinfolds. That is why they are used in contest prep for bodybuilding shows. Body fat was measured with skinfolds. Therefore, body fat measurements during ketogenic period are completely meaningless. DEXA would have been a better choice, and would have very likely put the lie to the numbers.

 

4) As mentioned, the test criteria were NOT measures of strength for an elite gymnast, they were measures of strength-endurance. Elite gymnasts are not endurance athletes, so they do not specifically train for endurance performance, making these tests a doubly invalid way to assess their performance. The only one that was a reasonable choice was the countermeasure jump. Even so, this is not something that gymnasts do: They rebound with virtually unbent legs. We call it a punch around here, and it is a completely different movement, but that is a discussion for a different forum. It is unsurprising, given some context, that this is one more area where their assessment was literally meaningless in the context of measuring strength or performance.

 

I hope you can see that if you are paying any attention to this study at all, other than to learn how to identify bad research methods, you are basically barking up the wrong tree and taking the word of a charlatan as truth.