Metabolic effects of high-intensity interval training and essential amino acids

AbstractHigh-intensity interval training (HIIT) promotes positive cardiometabolic and body composition changes. Essential amino acids (EAA) may support changes associated with HIIT, but evaluation of potential synergistic effects is lacking. The purpose of this study was to compare independent and combined effects of HIIT and EAA on total body composition and metabolism in men and women considered overweight/obese; an exploratory aim was to evaluate the modulatory effects of sex. Sixty-six healthy adults (50% female; Age: 36.7  ± 6.0 years; BMI: 32.0 ± 4.2 kg/m2) completed 8 weeks of: (1) HIIT, 2 days/weeks; (2) EAA supplementation, 3.6  g twice daily; (3) HIIT + EAA; or (4) control. Body composition, resting metabolic rate (RMR), substrate metabolism (respiratory exchange ratio; RER), and cardiorespiratory fitness were measured at baseline, 4 weeks, and 8 weeks; cardiometabolic blood markers were measured at baseline and 8 we eks. Differences between groups were assessed by linear mixed models covaried for baseline values, followed by 95% confidence intervals (CI) on adjusted mean change scores. There were no significant changes in body composition (p >  0.05) for any group. Changes in RER, but not RMR, occurred with HIIT (mean change; [95% CI]: − 0.04; [− 0.07, − 0.02]) and EAA (− 0.03; [− 0.06, − 0.01]) after 8 weeks. Cardiorespiratory fitness increased following 8 weeks of HIIT (+ 5.1 ml/kg/min [3.3,6.8]) and HIIT  + E...
Source: European Journal of Applied Physiology - Category: Physiology Source Type: research