Nutritional interventions for exercise-induced muscle damage: an umbrella review of systematic reviews and meta-analyses of randomized trials

CONTEXT: Several meta-analyses have been conducted on the effect of nutritional interventions on various factors related to muscle damage. However, the strength of the evidence and its clinical significance are unclear. OBJECTIVES: This umbrella review aimed to provide an evidence-based overview of nutritional interventions for exercise-induced muscle damage (EIMD). DATA SOURCES: PubMed, Scopus, and ISI Web of Science were systematically searched up to May 2022. DATA EXTRACTION: Systematic reviews and meta-analyses of randomized controlled trials investigating nutritional interventions' effects on recovery following EIMD were included. The certainty of the evidence was rated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE). RESULTS: Fifty-three randomized controlled trial meta-analyses were included, evaluating 24 nutritional interventions on 10 different outcomes. The results revealed a significant effect of hydroxymethylbutyrate (HMB) supplementation and l-carnitine supplementation for reducing postexercise creatine kinase; HMB supplementation for reducing lactate dehydrogenase; branched-chain amino acids and leaf extract supplementation for reducing the delayed onset of muscle soreness; and l-carnitine, curcumin, ginseng, polyphenols, and anthocyanins for reducing muscle soreness, all with moderate certainty of evidence. CONCLUSIONS: Supplementation with HMB, l-carnitine, branched-chain amino acids, curcumin, ginseng, leaf extract, polyphenols, and anthocyanins showed favorable effects on some EIMD-related outcomes. PROTOCOL REGISTRATION: PROSPERO registration no. CRD42022352565.