絆を深めるグリーンエクササイズ：人と犬の二者間における共有された自然ベースの身体活動のためのワンヘルスフレームワーク

Modern lifestyles are increasingly plagued by physical inactivity, social disconnection, digital addiction, and excessive time indoors-factors that negatively impact the health and well-being of both humans and their companion dogs (Canis familiaris). Evidence shows that nature exposure, physical activity, and human-animal bond (HAB) each enhance physical, mental, and social well-being, yet these domains have rarely been examined together as an integrated therapeutic triad. We introduce a new conceptual framework of bonded green exercise, defined as shared physical activity between a bonded human and dog in natural environments. Synthesizing existing evidence across human and canine sciences into a testable conceptual integration, we posit that bonded green exercise may plausibly activate evolutionarily conserved, synergistic mechanisms of physiological, behavioural, and affective co-regulation. Four testable hypotheses are proposed: (H1) triadic synergy: combined domains produce greater benefits than additive effects; (H2) heterospecific benefit: parallel health gains occur in both species; (H3) behavioural amplification: dogs acts as catalysts to drive human participation in nature-based activity; and (H4) scalable health promotion: bonded green exercise represents a low-cost, accessible, One Health approach with population-level potential. This framework highlights how intentional, shared physical activity in nature may potentially offer a novel low-cost and accessible model for enhancing health, lifespan, welfare, and ecological stewardship across species.