The Effect of a Multi-Ingredient Pre-Workout Supplement on Time to Fatigue in NCAA Division I Cross-Country Athletes

Abstract

This investigation aimed to determine the effect of a multi-ingredient pre-workout supplement (MIPS) on heart rate (HR), perceived exertion (RPE), lactate concentration, and time to fatigue (TTF) during a running task to volitional exhaustion. Eleven NCAA Division I cross-country runners (20 ± 2 year; height: 171 ± 14 cm; weight: 63.5 ± 9.1 kg) participated in this randomized, double-blind, placebo-controlled cross-over study. Bayesian statistical methods were utilized, and parameter estimates were interpreted as statistically significant if the 95% highest-density intervals (HDIs) did not include zero. TTF was increased in the MIPS condition with a posterior Mean_diff = 154 ± 4.2 s (95% HDI: -167, 465) and a 0.84 posterior probability that the supplement would increase TTF relative to PL. Blood lactate concentration immediately post-exercise was also higher in the MIPS condition compared to PL with an estimated posterior Mean_diff = 3.99 ± 2.1 mmol (95% HDI: -0.16, 7.68). There were no differences in HR or RPE between trials. These findings suggest that a MIPS ingested prior to sustained running at lactate threshold has an 84% chance of increasing TTF in highly trained runners and may allow athletes to handle a higher level of circulating lactate before reaching exhaustion.

Keywords: acute; caffeine; endurance; ergogenic aid; multi-ingredient pre-workout supplement; running performance; sports nutrition.

Figure 1

Supplement label information for the PerformElite™.

Figure 2

Percent change in time to fatigue in the supplement condition relative to the placebo control. Percent change between the conditions was calculated as follows: [((Supplement/Placebo) − 1) × 100]. Eight of the eleven subjects (72.7%) experienced an increased TTF in the supplement condition relative to the placebo, with an average increase of 6.2 ± 11.0%.