Collins, Patrick Blaise (2017-12). Short-Term Effects of a Ready-To-Drink Pre-Workout Beverage on Exercise Performance and Recovery. Doctoral Dissertation.
Thesis
The effects of ingesting a ready-to-drink pre-workout supplement (RTD) on exercise performance were assessed in this dissertation. Resistance-trained participants (n=25, 24 +- 4 y) ingested in a double-blind, crossover study a: (1) Dextrose placebo (PLA, 12 g) and, (2) RTD containing caffeine (200 mg), ?-alanine (2.1 g), niacin (65 mg), folic acid (325 mcg), Vitamin B12 (45 mcg), and arginine nitrate (1.3 g) for 7 d, interspersed by 7 d washout. Data were analyzed by univariate, multivariate, and repeated measures general linear models (GLM), adjusted for gender and relative caffeine intake. Data are presented as mean change (95% CI). An overall multivariate time x treatment interaction was observed on strength performance variables (p = 0.01). Acute RTD ingestion better maintained LP 1-RM (PLA: -0.285 (-0.49, -0.08); RTD: 0.23 (-0.50, 0.18) kg/kgFFM, p = 0.30); increased LP RtF (PLA: -2.60 (-6.8, 1.6); RTD: 4.00 (-0.2, 8.2) repetitions, p = 0.031); increased BP lifting volume (PLA: 0.001 (-0.13, 0.16); RTD: 0.03 (0.02, 0.04) kg/kgFFM, p = 0.007); and, increased total lifting volume (PLA: -13.12 (-36.9, 10.5); RTD: 21.06 (-2.7, 44.8) kg/kgFFM, p = 0.046). Short-term RTD ingestion maintained baseline LP 1-RM (PLA: -0.412 (-0.08, -0.07); RTD: 0.16 (-0.50, 0.18) kg/kgFFM, p = 0.30); LP RtF (PLA: 0.12 (-3.0, 3.2); RTD: 3.6 (0.5, 6.7) repetitions, p = 0.116); and, LP lifting volume (PLA: 3.64 (-8.8, 16.1); RTD: 16.25 (3.8, 28.7) kg/kgFFM, p = 0.157) to a greater degree than PLA. No significant differences were observed between treatments in cycling TT performance, hemodynamic assessment, fasting blood panels, or self-reported side effects. Within the confines of this study, the RTD examined appears to be safe and provides an ergogenic benefit for total lifting volume by enhancing muscular endurance; however, it does not appear to be ergogenic to 4 km time trial performance in non-trained cyclists.
