Effects of L-Carnitine Intake on Exercise-Induced Muscle Damage and Oxidative Stress: A Narrative Scoping Review

Area of Science:

• Exercise Physiology
• Biochemistry
• Nutritional Science

Background:

• Exercise-induced muscle damage triggers inflammation and oxidative stress, impairing physical performance.
• Phagocytes infiltrate muscle tissue for repair, but release free radicals, contributing to cellular damage.
• L-carnitine is vital for energy metabolism and possesses antioxidant properties, protecting against oxidative damage.

Purpose of the Study:

• To critically evaluate the efficacy of L-carnitine supplementation on exercise-induced muscle damage.
• To assess L-carnitine's impact on postexercise inflammatory and oxidative stress.
• To explore L-carnitine's effects on perceived fatigue and delayed onset muscle soreness.

Main Methods:

• Narrative scoping review of existing studies on L-carnitine supplementation and exercise-induced muscle damage.
• Analysis of studies investigating L-carnitine's role in muscle bioenergetics and antioxidant potential.
• Examination of research on L-carnitine's effects on inflammation, oxidative stress, and recovery.

Main Results:

• L-carnitine supplementation increases serum L-carnitine levels, correlating with reduced cell damage in oxidative stress conditions.
• Limited studies jointly assessed inflammation and oxidative damage, though L-carnitine's antioxidant role is established.
• Some studies indicated L-carnitine may influence fatigue perception and delayed onset muscle soreness.

Conclusions:

• L-carnitine's antioxidant and bioenergetic roles suggest potential benefits for postexercise recovery.
• Supplementation may mitigate exercise-induced muscle damage, inflammation, and oxidative stress.
• Further research is required to elucidate the precise mechanisms and confirm L-carnitine's efficacy.