Background
The oxidative handicap hypothesis posits that testosterone-dependent traits, such as muscle mass and strength, may be costly to develop due to testosterone's pro-oxidative properties, leading to increased oxidative stress. This hypothesis suggests that only individuals with superior biological conditions can afford these costs. This study examines the oxidative handicap hypothesis, exploring the relationship between muscle mass or handgrip strength and oxidative stress markers in men.
Conclusions
The study's findings do not support the oxidative handicap hypothesis in the context of muscle parameters in men. The results suggest that testosterone-driven traits like handgrip strength or muscle mass may not necessarily incur oxidative stress costs in healthy young men, possibly due to effective compensatory antioxidant mechanisms. Factors like lifestyle, diet, and genetic predisposition, which were not controlled in this study, could also influence the observed outcomes and should be included in future research.
Methods
Handgrip strength and muscle mass were measured in 179 men, with muscle mass assessed using bioelectrical impedance analysis (BIA) and handgrip strength measured using a hydraulic dynamometer. Serum testosterone levels and antioxidant capacity were measured. 8-OH-dG, 8-epi-PGF2α, and protein carbonyls were measured to evaluate oxidative stress level. Pearson's correlation and multivariate regression analyses were performed to examine the relationships between handgrip strength, muscle mass, and oxidative stress markers, controlling for age, serum testosterone levels, and antioxidant capacity.
Results
No significant correlations were found between handgrip strength and oxidative stress markers, even when controlling for muscle mass, antioxidant capacity, testosterone levels, and age. Conclusions: The study's findings do not support the oxidative handicap hypothesis in the context of muscle parameters in men. The results suggest that testosterone-driven traits like handgrip strength or muscle mass may not necessarily incur oxidative stress costs in healthy young men, possibly due to effective compensatory antioxidant mechanisms. Factors like lifestyle, diet, and genetic predisposition, which were not controlled in this study, could also influence the observed outcomes and should be included in future research.