The Effects of a Pre-workout Supplement on Measures of Alertness, Mood, and Lower-Extremity Power

Abstract

Objective The purpose of this study was to investigate the effects of a multi-ingredient pre-workout supplement (MIPS) on mental and physical performance. Materials and methods Fourteen exercise-trained men (n=7) and women (n=7) completed this randomized, placebo-controlled, double-blind, counterbalanced, crossover trial. Participants consumed either a MIPS or a placebo in a randomized, counterbalanced order. Forty-five minutes after consumption, the following assessments were conducted: psychomotor vigilance test (PVT), Profile of Mood States (POMS), vertical jump test, and heart rate and blood pressure. There was a one-week washout period between assessments. Results Statistically significant differences were observed between the treatment and placebo groups for the PVT (reaction time: treatment: 286 ± 28 ms, placebo: 306 ± 46 ms, p=0.0371) and POMS (i.e., vigor: treatment: 15.2 ± 14.9, placebo: 9.7 ± 9.6, p=0.0403; fatigue: treatment: 1.0 ± 1.1, placebo: 3.3 ± 3.4, p=0.0100). There were no significant differences between groups for the other indices of mood, false starts from the PVT, and vertical jump. Conclusion Based on our findings, the acute consumption of a MIPS produced a significant improvement in a sustained-attention, reaction-timed task as well as measures of vigor and fatigue.