Sedentary behavior (SB) and insufficient physical activity (PA) are established contributors to cardiometabolic disease risk, including type 2 diabetes mellitus and cardiovascular disease. A systematic review and meta-analysis published in the European Journal of Preventive Cardiology evaluated how characteristics of PA bouts, including frequency, duration, and intensity, are associated with cardiometabolic outcomes in acute experimental settings.

Studies included adults aged 18 to 65 years, with or without cardiometabolic conditions, comparing PA interventions with sedentary control conditions. Searches were conducted in PubMed, Cochrane Central, Embase, and Web of Science through February 2025. Random-effects models were used to estimate pooled standardized mean differences (SMDs) with 95% confidence intervals (CIs), with subgroup and meta-regression analyses exploring potential moderators.

A total of 144 studies (247 intervention arms; 2216 participants) were included. Frequent PA bouts were associated with lower blood glucose levels (SMD −0.22; 95% CI −0.27 to −0.16). Longer duration and/or higher intensity PA bouts were associated with reductions in triglycerides (SMD −0.27; 95% CI −0.34 to −0.19), with significant duration-by-intensity interactions for glucose (P=0.032) and triglycerides (P<0.001). Moderate-to-vigorous PA bouts were associated with improved endothelial function, reflected by increases in flow-mediated dilation (SMD 0.88; 95% CI 0.47 to 2.24) and shear rate (SMD 0.54; 95% CI 0.31 to 0.78).

PA bouts were also associated with lower insulin levels (SMD −0.26; 95% CI −0.32 to −0.19), systolic blood pressure (SMD −0.29; 95% CI −0.39 to −0.19), and diastolic blood pressure (SMD −0.16; 95% CI −0.26 to −0.05). These findings reflect acute responses to PA interventions across different bout characteristics.