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. 2019 Apr 25;7(4):95.
doi: 10.3390/sports7040095.

The Effects of Acute Caffeine Supplementation on Performance in Trained CrossFit Athletes

Jesse A Stein  1 , Melitza Ramirez  2 , Katie M Heinrich  3
Affiliations

The Effects of Acute Caffeine Supplementation on Performance in Trained CrossFit Athletes

Jesse A Stein et al. Sports (Basel). .

Retraction in

Abstract

Caffeine's ergogenic effects persist during various exercise modalities; however, information establishing its efficacy during CrossFit protocols is limited. Our study aimed to determine the effects of caffeine supplementation on CrossFit performance. Thirteen CrossFit-trained men (age = 28.5 ± 6.6 years, experience = 49.2 ± 36.3 months) were randomized in a double-blind, crossover design. Participants completed two sessions separated by a seven-day washout period, 60 min after consuming 5 mg/kg body mass of caffeine or a placebo. In each session, participants completed as many rounds as possible in 20 min of 5 pull-ups, 10 push-ups, and 15 air squats. CrossFit performance was the total number of repetitions completed in 20 min. Paired samples t-tests were used to compare CrossFit performance between caffeine and placebo conditions and to test for a potential learning effect between the first and second sessions. CrossFit performance was significantly higher during the caffeine condition compared to the placebo (461.4 ± 103 vs. 425.0 ± 93.5 repetitions, p < 0.05). No significant learning effect was identified between the first and second sessions (445.6 ± 95.0 vs. 440.8 ± 105.0 repetitions, p = 0.73) nor was there a significant treatment order effect (p = 0.40). Caffeine's ergogenic effect is present during CrossFit; however, future investigations should establish caffeine's efficacy during other CrossFit protocols and among female athletes.

Keywords: ergogenic aids; exercise; high intensity functional training; males; muscular endurance; sports nutrition.

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Conflict of interest statement

The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.

Figures

Figure 1
Figure 1
Performance (i.e., repetitions performed) in the caffeine and placebo condition. Data represent mean ± SD. * Significantly different from performance during the placebo condition p < 0.05.
Figure 2
Figure 2
Perceptual responses to exercise (i.e., ratings of perceived exertion (RPE)) in the caffeine and placebo condition. Data represent mean ± SD.
Figure 3
Figure 3
Percent change in performance [(repetitions completed with caffeine − repetitions completed with placebo)/(repetitions completed with placebo) × 100)] in the caffeine and placebo condition for each participant.
See this image and copyright information in PMC

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