Physical activity linked to improved HbA1c in Type 2 diabetics
MedWire News: Researchers demonstrate that improved cardiorespiratory fitness, achieved though aerobic and resistance exercise training, is associated with significant reductions in glycated hemoglobin (HbA1c) in individuals with Type 2 diabetes.
Writing in the journal Diabetologia, Glen Kenny (University of Ottawa, Ontario, Canada) and colleagues report results from a study of 251 patients with Type 2 diabetes who were randomly assigned to participate in aerobic, resistance, or aerobic and resistance exercise for 6 months.
They found that aerobic and resistance training alone led to significant 0.51% and 0.38% reductions in HbA1c, respectively, over the study period.
Combined exercise training led to greater reductions in HbA1c at 6 months than those achieved by the aerobic and resistance training groups, with respective additional reductions of 0.46% and 0.59%.
To assess fitness, the researchers measured peak oxygen consumption (VO2 peak), workload, treadmill time, and ventilator threshold measurements from maximal treadmill exercise testing both at study enrollment and at 6 months.
The team found that for the aerobic group the beneficial changes in HbA1c were linked to improvements in VO2 peak and workload, whereas improvements in strength on the seated rowing machine and in mid-thigh muscle cross-sectional area were associated with improved HbA1c in the resistance group.
For the combined group, improvements in VO2 peak, workload, and ventilatory threshold were most significantly linked with HbA1c decreases. Of note, in this group increases in muscle cross-sectional area were not significantly linked with improved HbA1c.
"Both aerobic and resistance exercise training alone cause clinically important improvements in physical fitness and glycemic control," summarize the authors.
"However, the association between changes in physical fitness and glycemic control may be more pronounced with combined exercise training due to improvements in aerobic fitness and in muscular strength," they suggest.
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By Helen Albert