Bioelectrical Phase Angle, Muscle Damage Markers and Inflammatory Response After a Competitive Match in Professional Soccer Players

Abstract Introduction. The purposes of this study were 1) to evaluate changes from baseline levels in bioelectrical phase angle (PhA) and markers of muscle damage and inflammation in professional players 36 h after a soccer match, and 2) to analyze the relationships between PhA and markers of muscle damage and inflammation in order to investigate if PhA might be a useful parameter to monitor recovery. Material and methods. Eighteen male professional soccer players participated in this study. Plasma lactate dehydrogenase (LDH) and creatine kinase (CK) activities, plasma C-reactive protein (CRP) and interleukin-6 (IL-6) concentrations, and PhA were measured before and 36 h after a competitive match. Results. Changes in LDH and CK 36 h after the match were greater than their reference change values (RCV). Changes in CRP and IL-6 were, however, lower than their corresponding RCV. 36 h after the match, significant correlations were observed between PhA and LDH (r = 0.714, p = 0.001), PhA and CK (r = 0.787, p = 0.000), and PhA and CRP (r = 0.554, p = 0.017). Conclusions. Although IL-6 and CRP have been traditionally analyzed together to monitor inflammation after intense exercise, since 36 h after the match they have already returned or started to return to baseline levels, the use of them alone is not a good option to monitor inflammation throughout recovery. PhA might be used as a predictor of muscle damage and inflammation, but further studies covering the whole recovery period are warranted.