Effects of Pre- Versus Post-Exercise Nitrate Supplementation on Acute Recovery Following Flywheel Eccentric Exercise in Moderately Trained Individuals

Wong, Nicholas Jing Heng (2026) Effects of Pre- Versus Post-Exercise Nitrate Supplementation on Acute Recovery Following Flywheel Eccentric Exercise in Moderately Trained Individuals. Final Year Project (Bachelor), Tunku Abdul Rahman University of Management and Technology.

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Abstract

Exercise-induced muscle damage (EIMD) following eccentric contractions impairs neuromuscular performance and increases perceived muscle soreness, posing a significant challenge to athletic recovery. Nitrate supplementation via the nitrate–nitrite–nitric oxide pathway has emerged as a promising nutritional strategy, yet the optimal timing relative to exercise remains unclear. This study compared the effects of pre- versus post-exercise inorganic nitrate supplementation on acute recovery following flywheel eccentric exercise in moderately trained individuals. Twenty-one moderately trained male university students (age: 21.8 ± 1.4 years; body mass: 73.2 ± 13.6 kg) were randomly assigned to three parallel groups: pre-exercise nitrate (Pre-NIT, n = 7), post-exercise nitrate (Post-NIT, n = 7), or placebo (n = 7). All participants completed a single session of flywheel bilateral squat eccentric exercise (kBox 4 Pro; 4 × 8 repetitions) and received 8.4 mmol nitrate via 70 ml Beet It Sport beetroot juice concentrate (James White Drinks Ltd.) either 60 minutes pre-exercise or immediately post-exercise, with a nitrate-depleted placebo at the alternate time point. Acute recovery was assessed at baseline, 0 h, 24 h, and 48 h post-exercise using countermovement jump (CMJ) height (Vertec), maximal voluntary contraction (MVC) force via the VALD ForceFrame dynamometer, and perceived muscle soreness via the Visual Analogue Scale (VAS). Data were analysed using a linear mixed-effects model for repeated measures (MMRM) with baseline values as covariates. Neither Pre-NIT nor Post-NIT produced a clinically meaningful acute recovery benefit relative to Placebo, with no significant Group × Time interactions across all three outcomes. Both nitrate conditions reported higher soreness than Placebo, with statistically significant but clinically marginal differences at 0 h and 48 h that minimally exceeded the 1-point minimal clinically important difference on the VAS. These findings indicate that acute inorganic nitrate timing alone is insufficient as a standalone recovery strategy following a single flywheel eccentric overload session.