The Effect of Exercise Training and Diet, Alone, on Glycosylated Hemoglobin (HbA1c) and Fasting Glucose in Patients with Type 1 Diabetes: A Meta-Analysis Systematic Review

Type 1 diabetes (T1D) is an autoimmune disease. The best way to control T1D is to control blood sugar levels and change lifestyle, including proper diet and physical activity. This study aimed to investigate the effect of exercise and diet alone on glycated hemoglobin (HbA1c) and fasting glucose in patients with T1D.

A systematic search was conducted in PubMed, Web of Science, Scopus, and Google Scholar databases for English articles published until October 2022. A meta-analysis was performed to investigate the effect of exercise and diet, alone, on HbA1c and fasting glucose in patients with T1D. Standardized mean difference (SMD), weighted mean difference (WMD), and 95% confidence interval were calculated using a random effect model.

The results of 14 studies with 637 boys and girls with T1D showed that exercise caused a significant decrease in HbA1c (P = 0.03, SMD = -0.55) in T1D patients compared to the control group. However, exercise did not significantly reduce fasting glucose (P = 0.07, WMD = -28.14 mg/dL) in T1D patients compared to the control group. Also, the diet did not significantly reduce HbA1c (SMD-0.04, P = 0.6) and fasting glucose (WMD-18.52 mg/dL, P = 0.1) in patients with T1D compared to the control group.

The present study shows that exercise training is suggested as a non-pharmacological solution to reduce HbA1c for T1D patients. According to the results of the present meta-analysis, the most appropriate exercise method to reduce HbA1c is combined exercise. However, diet alone does not affect HbA1c in patients with T1D.