Boniol M, et al. – Researchers performed a systematic review of randomized trials which assessed the effect of physical activity on the change in fasting glucose and HbA1c. This analysis illustrates that moderate increases in physical activity are correlated with significant reductions in both fasting glucose and HbA1c.

Methods

• Researchers performed a literature search in PubMed until December 2015.
• For this research, studies reporting glucose or HbA1c at baseline and at the end of study were included, and the change and its variance were estimated from studies with complete data.
• They applied mixed–effect random models to calculate the change of fasting glucose (mg/dl) and HbA1c (%) per additional minutes of physical activity per week.
• They recruited a sum of 125 studies in the meta–analysis.

Results

• Based on 105 studies, an increase of 100 min in physical activity per week was correlated with an average change of –2.75 mg/dl of fasting glucose (95% CI –3.96; –1.55), while there was a high degree of heterogeneity (83.5%).
• The average change in fasting glucose was –4.71 mg/dl (95% CI –7.42; –2.01) when restricting the analysis on type 2 diabetes and prediabetes subjects (56 studies).
• As evidence accumulates, for HbA1c, among 76 studies included, an increase of 100 min in physical activity per week was correlated with an average change of –0.14% of HbA1c (95% CI –0.18; –0.09) with heterogeneity (73%).
• Furthermore, a large degree of publication bias was distinguished (Egger test p < 0.001).
• It was noted that the average change in HbA1c was –0.16% (95% CI –0.21; –0.11) when restricting the analysis on type 2 diabetes and prediabetes subjects (60 studies).