Determining How Often and How Long to Break Up Sitting to Improve Heart and Metabolic Health in Adults An Adaptive Study Testing Different Sedentary Break Durations and Frequencies

What this Trial Is About

Researchers are investigating how often and for how long people should interrupt prolonged periods of sitting to improve heart and metabolic health. This Phase 1 study aims to find the smallest effective combination of break frequency and duration that can lower blood pressure and glucose levels. The trial also seeks to identify the highest tolerable break levels without causing physical or emotional distress, helping guide future public health recommendations. Participants will complete two 9-hour lab visits where they either remain seated continuously or take walking breaks on a treadmill at different frequencies and durations. The walking speeds are fixed, and breaks vary from every 30 to 120 minutes and last between 1 and 10 minutes. All participants will follow a controlled diet for two days before and during the visits. The study uses an adaptive randomization method to test 25 different break patterns efficiently. During each visit, participants wear heart rate and blood pressure monitors while researchers measure blood pressure and glucose at multiple times. They will also assess how well participants tolerate the breaks by checking fatigue, mood, safety, and ability to complete the protocol. The study involves 324 adults who will each experience both conditions in randomized order. The findings will help determine effective and acceptable sedentary break guidelines for cardiovascular health.

Breaking up Prolonged Sedentary Behavior to Improve Cardiometabolic Health