C-terminal agrin fragment is inversely related to neuromuscular fatigue in older men

ABSTRACT Introduction: The aim of this study was to examine the relationship between serum C‐terminal agrin fragment (CAF) concentrations and neuromuscular fatigue in older adults. Methods: Twenty‐two healthy older men and women volunteered for this study. Resting fasted blood samples were collected and prepared for measurement of serum CAF concentration by a commercially available ELISA kit. The onset of neuromuscular fatigue was measured by monitoring electromyographic fatigue curves from the vastus lateralis muscle using the physical working capacity at fatigue threshold (PWCFT) test. Results: A significant inverse correlation for men was observed between CAF and PWCFT (r = −0.602; P = 0.05), but not for women (r = 0.208; P = 0.54). After controlling for age and body mass index, significant correlations (r = −0.69; P = 0.042) remained for men, but not for women (r = 0.12; P = 0.76). Conclusions: These data suggest that serum CAF concentrations were significantly related to the onset of neuromuscular fatigue independent of age and BMI in men only. Muscle Nerve 51: 132–133, 2015