Effects of Carnitine Supplementation on Exercise-Induced Muscle Damage: A Randomized Controlled Trial

This clinical study aims to investigate the effects of L-carnitine supplementation on recovery following high-intensity interval exercise in young athletes. L-carnitine plays an important role in energy metabolism by facilitating the transport of long-chain fatty acids into the mitochondria for oxidation. It has been suggested that L-carnitine supplementation may contribute to improved exercise performance and recovery by reducing metabolic stress and muscle damage associated with high-intensity exercise. The primary objective of this study is to determine whether L-carnitine supplementation can attenuate exercise-induced muscle damage and delayed onset muscle soreness (DOMS) following high-intensity exercise. In addition, the study aims to evaluate the potential effects of L-carnitine on peak blood lactate concentration, as well as performance-related parameters including maximal power output, relative maximal power output, mean power output, and relative mean power output during high-intensity exercise. To address these objectives, participants will be randomly assigned to receive either L-carnitine supplementation or a placebo for a period of 21 days. The placebo will consist of an inert substance designed to resemble the supplement but without any active ingredient. The effects of supplementation on performance and recovery outcomes will be evaluated following a standardized high-intensity exercise protocol. Participants will be instructed to take the assigned supplement daily throughout the supplementation period. Communication and compliance monitoring will be conducted through a WhatsApp group established by the research team, which will be used to provide reminders and ensure adherence to the study protocol. To minimize potential confounding factors related to pre-existing muscle damage, participants will be instructed to avoid unfamiliar or strenuous physical activity, particularly resistance exercises involving eccentric contractions, for one week prio