A Single Dose of Microencapsulated Cocoa Supplementation Does Not Speed up Muscle Force Recovery after Eccentric Exercise-Induced Muscle Damage: A Placebo-Controlled, Double-Blind, Crossover Study

Abstract

Exercise-induced muscle damage is associated with symptoms such as inflammation, delayed-onset muscle soreness, and impaired muscle performance. The intake of cocoa polyphenols has been suggested to improve muscle recovery due to their antioxidant and anti-inflammatory capacity. However, their bioavailability presents a challenge. Therefore, food microencapsulation may be an alternative to protect polyphenols, ensuring their biological effects. This study aimed to investigate the effect of a single dose of microencapsulated cocoa on the changes in muscle damage markers after eccentric exercise. In this randomized, double-blind, crossover study, fourteen healthy volunteers with previous resistance training experience performed 6 × 10 maximal isokinetic eccentric contractions of their elbow flexors using an isokinetic dynamometer after ingesting 25 g of microencapsulated cocoa or placebo. Peak isometric torque was measured using maximal voluntary isometric contractions, and pain was measured using a visual analogic scale both before and 24 h, 48 h, and 72 h after the damage protocol. Plasma glutathione and malondialdehyde levels were measured using high-performance liquid chromatography, and concentrations of myoglobin and C-reactive protein were determined using a fluorescence immunoassay analyzer. Significant decreases were seen in the peak isometric torque and pain measures from pre- to 72 h post-eccentric exercise. A significant main effect for time was found only for plasma myoglobin at 2 h, 48 h, and 72 h, and for C-reactive protein at 2 h, compared to the pre-eccentric exercise values. No significant time-treatment effects were observed (all p > 0.05). This study demonstrated that microencapsulated cocoa cannot improve muscle recovery after eccentric exercise, at least when a single dose is consumed.