ABSTRACT
BACKGROUND: Assessing muscular strength (force-generating capacity) and exercise capacity in response to an intervention for people with type 2 diabetes is clinically important in the prevention of type 2 diabetes-related complications. OBJECTIVE: The purpose of this study was to investigate the impact of physical therapist-directed exercise counseling combined with fitness center-based exercise training on muscular strength and exercise capacity in people with type 2 diabetes. DESIGN: This study was a randomized clinical trial. SETTING: The study was conducted on a university campus, with patient recruitment from the local community. PATIENTS: Twenty-four people with type 2 diabetes were randomly allocated to either a group that received physical therapist-directed exercise counseling plus fitness center-based exercise training (experimental group) or a group that received laboratory-based, supervised exercise (comparison group). INTERVENTION: The experimental group received physical therapist-directed exercise counseling on an exercise program and was provided access to a fitness center. The comparison group received the same exercise program as the experimental group while under supervision. MEASUREMENTS: For all participants, chest press, row, and leg press muscular strength (1-repetition maximum [in kilograms]) and exercise capacity (graded exercise test duration [in minutes]) testing were conducted at baseline and 2 months later. RESULTS: No significant differences in improvements in muscular strength were found for the chest press (adjusted mean difference=1.2; 95% confidence interval [CI]=-5.5 to 7.8), row (adjusted mean difference=0.1; 95% CI=-9.0 to 9.1), or leg press (adjusted mean difference=2.7; 95% CI=-9.1 to 14.6) between the groups. No significant difference in improvement in exercise capacity (adjusted mean difference=0.2; 95% CI=-0.9 to 1.2) was found between the groups. LIMITATIONS: Lack of group allocation blinding and the small sample size were limitations of this study. CONCLUSIONS: The results suggest that physical therapist-directed exercise counseling combined with fitness center-based exercise training can improve muscular strength and exercise capacity in people with type 2 diabetes, with outcomes comparable to those of supervised exercise.