Dose-Dependent Effect of Supervised Aerobic Exercise on Hba1c in Patients With Type 2 Diabetes: A Meta-Analysis of Randomized Controlled Trials Publisher



Jayedi A^{1, 2} ; Emadi A³ ; Shabbidar S² Show Affiliations
Source: Sports Medicine Published:2022

Abstract

Background: Previous meta-analyses indicated that aerobic exercise can improve glycemic control. However, the optimum dose of exercise is still being discussed. Objective: The aim of this study was to examine the dose-dependent effect of supervised aerobic training (SAT) on glycated hemoglobin (HbA1c). Methods: We searched PubMed, Scopus, and Web of Science to May 2021 for randomized trials with an intervention period of 12 weeks or longer evaluating the effect of SAT on HbA1c in adults with type 2 diabetes mellitus. Secondary outcomes included quality of life, change in hypoglycemic medications, and adverse events. A random-effects dose–response meta-analysis was conducted. Results: The analysis of 26 trials with 1253 participants indicated that each 30-min/week SAT reduced HbA1c by − 0.22 percentage point (95% CI − 0.29 to − 0.15; GRADE = strong). Levels of HbA1c decreased proportionally with the increase in the duration of moderate to vigorous-intensity SAT to 100 min/week (mean difference100 min/week: − 0.96 percentage point, 95% CI − 1.25 to − 0.67), with flattening of the curve at higher duration. Aerobic exercise decreased antidiabetic medications by 13 per 100 patients (risk difference 0.13, 95% CI 0.02–0.23; 7 trials, n = 375; GRADE = moderate), and increased hypoglycemic reactions by 10 per 100 patients (risk difference: 0.10, 95% CI 0.03–0.17; 4 trials, n = 263; GRADE = low) and adverse events by 4 per 100 patients (risk difference: 0.04, 95% CI − 0.02 to 0.11; 2 trials, n = 236; GRADE = low). Limited evidence is available for quality of life. Conclusions: Every 30 min/week of moderate to vigorous aerobic exercise can exert a significant effect on HbA1c, with the highest effect observed from 100 min/week and above. However, exercise durations above 100 min/week seem ineffective for further reductions. Protocol Registration: PROSPERO (CRD42021257251). © 2022, The Author(s), under exclusive licence to Springer Nature Switzerland AG.