Objectives
Randomized, controlled trials have shown that exercise interventions reduce the incidence of type 2 diabetes in people with impaired glucose tolerance, and improve glycemic control, body composition and cardiorespiratory fitness in people with type 2 diabetes. We undertook the present systematic review to determine the extent to which participants in structured exercise trials continue to be physically active after the end of the interventions.
Methods
We systematically searched MEDLINE, EMBASE, CINAHL, SPORTDiscus and Cochrane Central Register of Controlled Trials for randomized, controlled trials that reported objective or self-reported physical activity levels in people with type 2 diabetes or prediabetes a minimum of 3 months after the end of a structured exercise intervention. This systematic review was registered on PROSPERO (PROSPERO CRD42018089468).
Results
Of 14,649 articles retrieved, 5 randomized, controlled trials (including 549 participants) were included in this systematic review. One study revealed significant improvements in self-reported physical activity levels in the intervention group compared with the control group 1, 3 and 5 years after baseline assessments, and decreased waist circumference, weight and body mass index at 1 year, but not 3 or 5 years. The 4 remaining studies did not find between-group differences at follow-up timepoints between 6 months and 3 years.
Conclusions
Future research should report physical activity levels at follow up to determine whether participation in a structured exercise intervention results in sustained increased physical activity levels. In addition, interventions should be evaluated for their effectiveness in improving adherence to long-term physical activity.