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: A Randomized Clinical Trial

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.