No Effect of Breakfast Consumption Observed for Afternoon Resistance Training Performance in Habitual Breakfast Consumers and Nonconsumers: A Randomized Crossover Trial

Background Pre-exercise meal frequency is commonly believed to impact exercise performance, but little is known about its impact on resistance training. Objective This study investigated the impact of breakfast consumption on afternoon resistance training performance in habitual breakfast consumers and nonconsumers. Design A randomized, crossover study was conducted in Lubbock, TX between November 2021 and May 2022. Participants Thirty-nine resistance-trained male (n = 20) and female (n = 19) adults (mean f SD age 23.0 f 4.7 years) who habitually consumed (>= 5 d/wk; n = 19) or did not consume (>= 5 d/wk; n = 20) breakfast completed the study. Intervention After the establishment of 1-repetition maximums at the first visit, participants completed 2 additional visits, each of which included 4 sets of barbell back squat, bench press, and deadlift, using 80% of their 1-repetition maximum after either consuming breakfast and lunch or the same food at lunch only. Main outcome measures Repetitions, along with average and peak average concentric velocity and power, were measured for all repetitions throughout each exercise session. Visual analog scales were used to assess feelings of fatigue, energy, focus, hunger, desire to eat, and fullness throughout each exercise session. Statistical analyses performed Data were analyzed using linear mixed-effects models. Results No interactions or main effects involving condition or habitual breakfast consumption were observed for resistance training outcomes, although sex differences were noted. Male participants performed significantly fewer repetitions on sets 2, 3, and 4 (P <.014) for total repetitions, on sets 2 and 4 for barbell back squat (P < .023), and set 4 for deadlift (P = .006), with no observed differences between sexes for bench press repetitions. Male participants displayed reductions in average power across all sets and exercises except deadlift. Conclusions These data suggest that alterations in pre-exercise meal frequency may not influence afternoon resistance training performance provided similar total nutritional intake is consumed.