Monitoring Muscle Oxygen Asymmetry as a Strategy to Prevent Injuries in Footballers.

It has been hypothesized that sports injury risk is explained by muscle metabolism. The objective was to evaluate the muscle oxygen saturation slopes (ΔSmO slopes) and muscle oxygenation asymmetry (MOAsy) at rest and to study their associations with injuries during the pre-season. A total of 16 male and 10 female footballers participated in this study. Injuries were diagnosed and classified by level of severity during the pre-season. The workload was also evaluated using the rate of perceived exertion × training time, from which the accumulated loads. The SmO was measured at rest in the gastrocnemius muscle using the arterial occlusion method in the dominant and non-dominant legs. The repeated measures ANOVA, relative risk, and binary logistic regression were applied to assess the probability of injury with SmO and workload. Higher MOAsy and ΔSmO Slope 2 were found among footballer who suffered high-severity injuries and those who presented no injuries. In addition, an MOAsy greater than 15% and an increase in accumulated load were variables that explained a greater probability of injury. This study presents the new concept of muscle oxygenation asymmetry in sports science and its possible application in injury prevention through the measurement of SmO at rest.