Effects Of A Single Dose Multi-Ingredient Pre-Workout Supplement On Aerobic Performance In Men And Women

Abstract

PURPOSE: To assess the effects of a single dose of a multi-ingredient pre-workout supplement (MIPS) on aerobic exercise performance, specifically exercise time and VO2max. METHODS: 41 college-aged adults (age: 21.8±2.5 y; BMI: 25.1±3.0 kg/m2; men=19; women=22) were recruited to participate in a randomized, double-blind, placebo-controlled, crossover study. All of the participants were tested in the same week, but separated by 48 hours, and were either provided the MIPS or the placebo (PLA) on each day. As per the manufacturer’s instructions, following the consumption of the drink, the participants waited 25 minutes to begin the test. Aerobic exercise performance was assessed using the Modified Astrand Treadmill Protocol, during which maximal oxygen consumption (VO2max) and maximal treadmill time were determined. At maximal treadmill time, heart rate (HR), respiratory exchange ratio (RER), and rating of perceived exertion (RPE) were collected. All data were analyzed using gender × trial ANOVAs. In the event of a non-significant interaction, data were analyzed as a single group using dependent t-tests. Alpha level was set to p≤0.05. All comparisons between PLA and MIPS trials were assessed using Cohen’s d effect sizes. All data is presented as mean±standard deviation. RESULTS: No significant gender × trial interactions were observed for any of the data. However, when assessed as a single group there was a significant difference in VO2max (p=0.038) with MIPS (43.8±6.9 mL/kg/min) performing better than PLA (43.0±6.5 mL/kg/min). Furthermore, maximal treadmill time was significantly different (p=0.016) with MIPS (9.4±1.9 min) performing better than PLA (9.0±1.8 min). Cohen’s d effect sizes revealed that the differences in VO2max (d=0.111) and exercise time (d=0.178) were trivial. There were no significant differences between PLA and MIPS for HR, RER, or RPE. CONCLUSIONS: A single dose of this MIPS improved maximal treadmill time and VO2max; however, these changes were not very large in magnitude. Future research should investigate the long-term effects of using this MIPS.