Accumulating Physical Activity in Short or Brief Bouts for Glycemic Control in Adults With Prediabetes and Diabetes

The Effects of Accumulated Versus Continuous Exercise on Postprandial Glycemia, Insulin, and Triglycerides in Adults with or Without Diabetes: A Systematic Review and Meta-Analysis

“…Although there was one narrative review [ 18 ], no meta-analysis has compared 2–3 short bouts, with a single bout, of exercise on PPG. Chang et al [ 18 ] suggested that three short bouts of accumulated, compared with a single bout of continuous, activity lead to similar or superior effects on glycemic control in individuals with prediabetes and type 2 diabetes. Our meta-analysis showed no differences in either same-day or second-morning PPG responses between 2–3 bouts of exercise and a single bout of energy-matched exercise.…”

“…If at least ten trials were included in a meta-analysis, we investigated publication bias using funnel plots to explore the possibility of small study effects (i.e., a tendency for smaller studies to report larger beneficial effects). As accumulated exercise in the included studies could be summarized into two patterns, PA breaks and 2–3 short bouts timed around daily main meals, we performed subgroup analysis based on the number of exercise bouts [ 18 ]. One study showed that PA breaks may be better at attenuating PPG levels in young active individuals than three bouts of energy-matched exercise before or after each meal [ 27 ].…”

“…One study showed that PA breaks may be better at attenuating PPG levels in young active individuals than three bouts of energy-matched exercise before or after each meal [ 27 ]. Previous reviews have examined the two patterns of accumulated exercise separately [ 18 , 23 ] to ensure that interventions were sufficiently homogeneous for comparison, or included studies with PA breaks only [ 17 , 19 ]. Subgroup analysis was also performed for exercise intensity, as this may affect PPG and insulin responses [ 23 , 28 ].…”

“…Several studies [ 14 – 16 ] and reviews [ 17 – 19 ] have shown that multiple postprandial bouts of exercise elicit greater improvements to PPG levels compared to a single exercise bout, with some studies indicating that continuous exercise has a comparable [ 13 ] or superior [ 20 ] effect than accumulated exercise. It should be noted that the two commonly used accumulating exercise patterns in these previous studies were frequent brief bouts (e.g., 1–6 min) throughout the day at 20–60-min intervals (known as physical activity [PA] breaks, ≥ 5 bouts), and three short bouts (e.g., 10–15 min) timed around the main meals at 3–5-h intervals [ 18 ].…”

“…Chang et al [ 18 ] included both patterns of accumulated exercise and showed that three short bouts (e.g., 10–15 min) of exercise timed around daily main meals were comparable or superior to a single continuous bout for improving glycemic control in individuals with type 2 diabetes, while the benefits of PA breaks, compared to a single bout of continuous activity, for improving glycemic control were unclear. However, only individuals with diabetes or pre-diabetes were included, only glucose outcomes were examined, and a meta-analysis was not conducted in the above-mentioned review [ 18 ]. Moreover, same-day and second-morning effects were not analyzed independently against PPG [ 17 – 19 ]; these effects may produce different outcomes [ 23 ].…”