Effects of circuit training on body composition and peak cardiorespiratory responses in patients with moderate to severe traumatic brain injury

Objective: To examine the time course of the changes in body composition and peak cardiorespiratory fitness resulting from routine brain injury rehabilitation program (BIRP) activities and circuit training in patients with moderate to severe traumatic brain injury (TBI). Design: Time-series design spanning 18 weeks. Trials T1 and T2 were completed in weeks 1 and 2, respectively, to establish reliability of the measurements, followed by trial 3 (T3) 4 weeks later to evaluate changes resulting from the BIRP. Setting: A BIRP in a community rehabilitation hospital. Setting: A BIRP in a community rehabilitation hospital. Participants: Fourteen inpatients with moderate to severe acquired TBI (Glasgow Coma Scale score, 4.6+/-1.4; time since injury, 17.2+/-17mo). Interventions: Twelve-week circuit-training program designed to enhance muscular strength and endurance and aerobic fitness. Subjects were tested midway (T4) through the program and at the end (T5) of 12 weeks. The patients completed an average of 32 supervised sessions, each lasting 1 hour. Main Outcome Measures: Changes in body composition and peak cardiorespiratory responses. Results: No significant changes were observed in the body mass or percentage body fat during the study. The peak values of power output, oxygen uptake, and ventilation rate increased significantly as a result of training, with no concomitant increases in peak heart rate or blood lactate (T5>T3, T2, T1; P<.05). No significant changes were evident midway through training. Conclusions: In a heterogeneous sample of patients with moderate to severe TBI, (1) body composition and peak cardiorespiratory responses remained fairly stable during 6 weeks of BIRP activities, (2) improvements in peak cardiorespiratory fitness required more than 6 weeks of circuit training, and (3) a 12-week course of circuit training without controlling caloric intake was not effective in reducing body weight or percentage body fat.