Branched chain amino acids and physical activity in a sample of healthy, non-obese people

Background Physical activity (PA) has been demonstrated to improve insulin sensitivity and reduce the risk of cardiovascular diseases. BCAA (branched chain amido acid) metabolism play a role in maintaining system energy homeostasis at rest and during activity, high BCAA levels being associated with an increased risk of cardiovascular disease (CVD) and diabetes. However, there is still limited research on the relationship between PA intensity and human plasma BCAA. Aims To assess the associations between BCAA (Valine, Leucine and Isoleucine) and PA in a somple of healthy, non-obese, middle-aged people. Methods Cross-sectional study using data from the CoLaus|PsyCoLaus study conducted in our city. BCAA concentrations were measured by stable isotope dilution liquid chromatography – mass spectrometry (LC-MS) assay. Time spent in PA was assessed by questionnaire and categorized into sedentary, light, moderate and vigorous intensity. Results On bivariate analysis, BCAA levels were significantly and positively associated with total energy expenditure and negatively with light PA and sleep time. Those findings were confirmed after multivariable analysis, a negative association between BCAA levels and duration of sleep, light and moderate PA, and a positive association between BCAA levels and total energy expenditure, sedentary behaviour and vigorous PA being observed (table). Conclusion sleep time, light and moderate intensity PA are negatively associated with BCAA, suggesting that the beneficial effects of PA on CVD could partly be mediated by decreases in BCAA levels. The unexpected positive association between total energy expenditure and vigorous PA with BCAA levels should be further explored.