Resistance Training Improves Muscle Function and Cardiometabolic Risks But Not Quality of Life in Older People With Type 2 Diabetes Mellitus: A Randomized Controlled Trial

BACKGROUND AND PURPOSE: In older people with type 2 diabetes mellitus (T2DM), the effects of aging and T2DM may compromise the function of skeletal muscle, deteriorate metabolic status, and jeopardize physical performance, aerobic capacity, and quality of life (QoL). The purpose of this study was to investigate the effects of 12 weeks of resistance training (RT) on muscle function, physical performance, cardiometabolic risks, and QoL in older people with T2DM. METHODS: This study was a randomized controlled trial that employed block randomization, assessor blinding, and the intention-to-treat principle. Thirty people 65 years or older with a diagnosis of T2DM were randomly assigned to either an exercise group or a control group and were further stratified by gender. The exercise group performed 8 RT exercises in 3 sets of 8 to 12 repetitions at 75% 1-repetition maximum (1-RM) 3 times per week for 12 weeks. The control group received usual care and maintained their daily activities and lifestyle. Muscle function (1-RM and muscle oxygenation responses), physical performance (5-repetition sit-to-stand test and Timed Up and Go test), cardiometabolic risks (aerobic capacity, blood pressure, body composition, glycemic control, lipids levels, and high-sensitivity C-reactive protein levels), and QoL (Audit of Diabetes-Dependent Quality of Life 19) were assessed at baseline (week 0) and after the 12-week interventions (week 12). RESULTS: The 1-RM chest-press and leg-press strength and physical performance in 5-repetition sit-to-stand test were significantly improved in the exercise group compared with the controls after the interventions. The exercise group had significantly lower resting systolic blood pressure (by -12.1 mm Hg, P = 0.036) than did the controls after 12 weeks of RT, without any significant within-group change in either group after intervention. The waist circumference, fasting glucose levels, and peak diastolic blood pressure tended to favor RT over usual care after the interventions. CONCLUSION: Twelve weeks of RT increased the maximal strength in chest-press and leg-press tests, and improved 5-repetition sit-to-stand performance in older people with T2DM. Our study demonstrated that supervised, structured RT was able to promote muscle function and alleviate cardiometabolic risks in people with T2DM 65 years or older.