Effect of metformin on exercise capacity: A meta-analysis.

AIMS

To evaluate the effect of metformin on various parameters of exercise capacity [oxygen consumption (VO), peak oxygen consumption (VO), heart rate (HR), exercise test duration, respiratory exchange ratio (RER), rating of perceived exertion (RPE), lactate and ventilatory anaerobic threshold (VAT)].

METHODS

Studies reporting change in VO or VO after metformin administration were included. Subgroup analyses were performed as applicable. Mean difference with 95% CIs were pooled using random-effects model [RevMan (v5.3)].

RESULTS

There were no changes in VO and VO in the overall population [VO: n = 388, mean difference: -0.12 ml/kg/min, 95% CI: -0.74, 0.51, p = 0.71 (i = 0%, p = 0.99); VO: n = 345, mean difference: 0.41 ml/kg/min, 95% CI: -0.51, 1.33, p = 0.38 (i = 0%, p = 0.89)], healthy volunteers and patients (type 2 diabetes mellitus, insulin resistance, impaired glucose tolerance/impaired fasting glucose and metabolic syndrome). For patients with insulin resistance, there was a decrease in VO, but not VO. In the overall population, there was a significant decrease in HR and RER, a significant increase in RPE, and no changes in exercise test duration and VAT. In addition, there was an increased VAT in the healthy volunteers.

CONCLUSIONS

In the overall population, metformin did not affect VO, VO, exercise test duration and VAT, although it significantly decreased HR, RER and increased RPE.