The Effect of Exercise on Quality of Life in Type 2 Diabetes: A Systematic Review and Meta-analysis.

BACKGROUND: Exercise is a proven therapy for managing cardiometabolic risk factors in type 2 diabetes (T2D). However, its effects on patient-reported outcome measures such as quality of life (QoL) in people with T2D remain unclear. Consequently, the primary aim of this study was to determine the effect of regular exercise on QoL in adults with T2D. A secondary aim was to determine the effect of different exercise modalities on QoL. The third aim was to determine whether improvements in QoL were associated with improvements in gly'cated hemoglobin (A1C). METHODS: Relevant databases were searched to May 2022. Eligible studies included randomized trials involving ≥2 wk of aerobic and/or resistance exercise and assessed QoL using a purpose-specific tool. Mean differences and 95% confidence intervals (CI) were calculated as standardized mean difference (SMD) or weighted mean difference. A regression analysis was undertaken to examine the interaction between change in QoL with change in A1C. RESULTS: Of the 12,642 studies retrieved, 29 were included involving 2354 participants. Exercise improved QoL when compared with control (SMD, 0.384; 95% CI, 0.257 to 0.512; P < 0.001). Aerobic exercise, alone (SMD, 0.475; 95% CI, 0.295 to 0.655; P < 0.001) or in combination with resistance training (SMD, 0.363; 95% CI, 0.179 to 0.548; P < 0.001) improved QoL, whereas resistance training alone did not. Physical components of health-related QoL (HRQoL) improved with all exercise modalities, but mental components of HRQoL remained unchanged. Exercise improved A1C (mean difference, -0.509%; 95% CI, -0.806% to -0.212%; P = 0.001), and this change was associated with improvements in HRQoL ( ß = -0.305, SE = 0.140, Z = -2.18, P = 0.030). CONCLUSIONS: These results provide robust evidence that regular aerobic exercise alone or in combination with resistance training is effective for improving QoL in adults with T2D. Such improvements seem to be mediated by improvements in physical components of HRQoL and are associated with improved blood glucose control. Further studies should be undertaken to determine the relative importance of exercise duration, intensity, and frequency on patient-reported outcomes such as QoL.