Eight Weeks of Exercise Training Improves Fitness Measures in Methamphetamine-Dependent Individuals in Residential Treatment

Abstract

Physical exercise has been shown to benefit diverse medical and behavioral conditions. This study assesses the feasibility and efficacy of an 8-week endurance and resistance training program on fitness measures in individuals undergoing residential treatment for methamphetamine (MA) dependence. A total of 39 MA-dependent individuals were randomized to 3 days/week of exercise training (ET, n = 15) or health education without training (equal attention [EA], n = 14) over 8 weeks. Aerobic performance ((Equation is included in full-text article.)VO2max) was measured by indirect calorimetry, body composition by skinfolds, muscle strength by 1-repetition maximum (1-RM), and endurance at 85% of 1-RM for both leg press (LP) and chest press (CP). A total of 29 individuals completed the study for a 74% adherence rate. Baseline characteristics (mean ± SD) were balanced between groups: age 31 ± 7 years; height = 1.74 ± 0.07 m; weight 82.0 ± 15.0 kg. The ET group significantly improved (Equation is included in full-text article.)O2max by 0.63 ± 0.22 L/min (+21%), LP strength by 24.4 ± 5.6 kg (+40%), and CP strength by 20.6 ± 5.7 kg (+49%). The ET group increased LP and CP endurance by 120% and 96%, respectively and showed significant reductions in body weight of 1.7 ± 2.4 kg (-2%), % body fat of 2.8 ± 1.3% (-15%), and fat weight 2.8 ± 1.8 kg (-18%). All changes were significant (P < 0.001) for ET, and no changes were seen for the EA group. Individuals recovering from MA dependence showed substantial improvements in aerobic exercise performance, muscle strength and endurance, and body composition with ET. These findings demonstrate the feasibility of an ET intervention in these participants and also show excellent responsiveness to the exercise stimulus resulting in physiological changes that might enhance recovery from drug dependency.