Yuri Tominaga

ABSTRACT Aim Beyond structured physical activity, emerging evidence suggests the potential health benefits of incidental lifestyle physical activity (ILPA). However, the relationship between ILPA and frailty or frailty domains in older populations remains unclear. Methods A total of 15 302 community‐dwelling adults aged 65 years and older in Osaka, Japan, were invited to participate in a mailed survey. The survey included a single‐item question asking about participants' ILPA: “Are you trying to be physically active in your daily life, for example, through housework or transportation?” Frailty outcomes, including overall frailty and frailty domains (physical, nutritional, oral, social, cognitive, and mental), were assessed using the validated Kihon Checklist based on its scoring manual. Logistic regressions were used to investigate associations between ILPA and overall frailty and each frailty domain. Age and sex differences were determined using subgroup analysis and interaction analysis. Results The response rate was 49.03%. Logistic regression analyses revealed ILPA is negatively associated with overall frailty and domains including physical, nutritional, oral, social, cognitive, and mental domains of frailty. Most associations were evident regardless of age and sex, while the association between ILPA and the physical domain of frailty was stronger in males ( p for interaction = 0.01), while the association with the mental domain of frailty was stronger in females ( p for interaction = 0.007). Conclusions In community‐dwelling older Japanese adults, ILPA was negatively associated with overall frailty and multiple domains of frailty. While structured physical activity remains critical, the findings underscore the importance of promoting increased ILPA in daily experience.