A complex systems view on physical activity with actionable insights for behavior change

The rising of physical inactivity and its associated health and economic burdens persist de-spite decades of interdisciplinary research aimed at promoting physical activity (PA). This Per-spective takes a complex systems view on PA, proposing that at least two layers of complexity should be taken into account: 1) interactions between various physiological, psychological, social, and environmental systems and 2) their dynamic interactions across time. To address this complexity, all stages of the research process—from theory and measurement to study design, analysis, and interventions—must be aligned with a complex systems perspective. This alignment requires intensive interdisciplinary collaboration and an integration of basic and applied research beyond current research practices to create transdisciplinary solutions. We offer actionable insights that bridge the gap between abstract theoretical approaches (e.g., complex systems and attractor landscape frameworks of behavior change) and practical PA research, thereby laying a foundation for more effective behavior change interventions.