Evaluating Movement Breaks As A Public Health Strategy To Combat Sedentary Behavior: A Large-scale Pragmatic Trial

Guidelines recommend reductions in sedentary time; however, they are vague on how to achieve reductions. Regular movement breaks have been tested in experimental studies and shown to be beneficial in offsetting the harms of sedentary behavior. However, whether and which movement breaks doses are effective and viable under real world settings remains unknown. Purpose: To examine the effectiveness and acceptability of different movement break doses among a large general sample of adults under real world conditions. Methods: This pragmatic trial included a general sample of 8,746 adults recruited via a collaboration with National Public Radio. Participants self-selected into 1 of 3 doses: movement breaks every 30 (31.6%), 60 (48.5%), or 120 min (19.9%). Breaks consisted of walking at a self-selected pace for 5 min. Each dose was instructed to take breaks at the specified frequency during waking hours for 2 weeks. Emotional health and fatigue were assessed pre-post with the Positive and Negative Affect Schedule and Fatigue Severity Inventory, respectively. Sedentary time and implementation measures were assessed using validated questionnaires. Results: Trial completion rates were 77.9, 79.0, and 79.9% and participants took, on average, 6.3 (SD: 4.1), 4.8 (SD: 2.6), and 3.3 (SD: 1.8) breaks per day for the every 30, 60, and 120 min doses, respectively. Sedentary time was significantly reduced across all doses (Figure Panel A). Positive affect was significantly increased and negative affect and fatigue were significantly decreased across all doses (Figure Panels B and C). Acceptability and appropriateness were rated (score range: 0-20) as moderate across all doses, however feasibility and acceptability were significantly lower for the every 30 min dose compared to the other doses (Figure Panel D). Conclusion: The present study demonstrates that movement breaks are a viable public health strategy to elicit reductions in sedentary time and improvements in well-being.