My Published Research: The First Human Clinical Trial on the Ketogenic Diet in CrossFit Athletes

In 2017, I completed the first-ever human clinical trial on the effects of the ketogenic diet in non-elite CrossFit athletes. It was my master's thesis at James Madison University, and it was published in the International Journal of Sports and Exercise Medicine.

I don't coach keto anymore. More on that below.

What the study found

Twenty-seven recreational CrossFit athletes trained four times a week for six weeks. Half followed a ketogenic diet, half kept eating the way they normally did.

The keto group lost significantly more weight and body fat than the control group. Both groups held onto their lean mass, and both got faster.

That last part is the finding worth sitting with: the fat loss happened without losing muscle.

What I coach now

I don't coach keto anymore. I still think it has its place for a small subset of the population, but my work now focuses on helping women 40+ build muscle instead of shrinking, with flexible structure in place of willpower and extremes.

If you've spent years losing the same weight and gaining it back, the way out is moving past the all-or-nothing framework, building the body of your dreams, and realizing that's possible way beyond your youth.

In this day and age, you might be able to buy skinny, but you can't buy strong and confident. Strong you build yourself, and that confidence bleeds into everything else.

The citation

Gregory RM, Hamdan H, Torisky DM, Akers JD (2017). A Low-Carbohydrate Ketogenic Diet Combined with 6-Weeks of Crossfit Training Improves Body Composition and Performance. International Journal of Sports and Exercise Medicine, 3:054. DOI: 10.23937/2469-5718/1510054.

The full abstract

Background

The purpose of this research was to examine the effects of a 6-week LCKD and CrossFit program on body composition and performance.

Methods

Twenty-seven non-elite CrossFit subjects (mean ± SD age = 34.58 ± 9.26 years) were randomly assigned to a LCKD (males, n = 3; females, n = 9) or control (CON) (males, n = 2; females, n = 13) group. LCKD was instructed to consume an ad libitum diet and restrict carbohydrate intake to less than 50 grams per day and CON maintained usual dietary intake. All subjects participated in four CrossFit training sessions per week during the 6 weeks.

Results

Compared to CON group, the LCKD group significantly decreased weight (0.18 ± 1.30, -3.45 ± 2.18 kg), BMI (0.07 ± 0.43, -1.13 ± 0.70 kg/m²), percent body fat (% BF) (0.01 ± 1.21, -2.60 ± 2.14 %), and fat mass (FM) (0.06 ± 1.12, -2.83 ± 1.77 kg), respectively. There was no significant difference in lean body mass (LBM) change between or within groups. We found no significant difference in total performance time change between groups; however, both groups significantly decreased total performance time (CON: -41.20 ± 43.17 sec.; LCKD: -55.08 ± 44.29 sec). Carbohydrate intake was significantly lower (11.4 ± 5.6%, 40.06 ± 6.81%) and fat intake was significantly higher (62.88 ± 4.19%, 38.38 ± 4.18%) in LCKD compared to CON, respectively.

Conclusions

Our data show that a LCKD combined with 6 weeks of CrossFit training can lead to significant decreases in %BF, FM, weight, and BMI while maintaining LBM and improving performance.

Follow this link for the full study!