The efects of continuous compared to accumulated exercise on health: a meta‑analytic review

Background Public health guidelines suggest that physical activity can be accumulated in multiple short bouts dispersed through the day. A synthesis of the evidence for this approach is lacking. Objective Our objective was to undertake a systematic review and meta-analysis to examine if exercise interventions consisting of a single bout of exercise compared with interventions comprising the same total duration, mode, and intensity of exercise accumulated over the course of the day have diferent efects on health outcomes in adults.

Methods Six electronic databases were searched (Jan 1970–29 August 2018). Two authors identifed studies that evaluated the efects of a single bout of exercise compared with the same intensity, total duration, and mode of exercise accumulated in multiple bouts over the course of a day, in community-dwelling adults. Risk of bias was assessed using the Cochrane Collaboration tool. Pooled efects were reported as standardised mean diferences (MDs) and 95% confdence intervals (CIs) using a random efects model.

 Results A total of 19 studies involving 1080 participants met the inclusion criteria. There were no diferences between accumulated and continuous groups for any cardiorespiratory ftness or blood pressure outcomes. A diference was found in body mass changes from baseline to post-intervention in favour of accumulated exercise compared with continuous (MD −0.92 kg, 95% CI −1.59 to −0.25, I 2=0%; fve studies, 211 participants). In subgroup analyses, accumulating >150 min of weekly exercise in multiple bouts per day resulted in small efects on body fat percentage (combined post-intervention and change from baseline values: MD −0.87%, 95% CI −1.71 to −0.04, I 2=0%; three studies, 166 participants) compared with 150 min of exercise amassed via single continuous bouts per day. There was a decrease in low-density lipoprotein (LDL) cholesterol with accumulated versus continuous exercise (MD −0.39 mmol/l, 95% CI −0.73 to −0.06, I 2=23%; two stud?ies, 41 participants). No diferences were observed for any other blood biomarker (total cholesterol, high-density lipoprotein cholesterol, triglycerides, fasting blood glucose, and fasting insulin).

Conclusions There is no diference between continuous and accumulated patterns of exercise in terms of efects on ftness, blood pressure, lipids, insulin and glucose. There is some evidence from a small number of studies that changes in body mass and LDL cholesterol are more favourable following the accumulated condition. Collectively our fndings suggest that adults are likely to accrue similar health benefts from exercising in a single bout or accumulating activity from shorter bouts throughout the day. This review will inform public health guidelines for physical activity at the global and national levels (PROSPERO 2016 CRD42016044122).