Foot impairment in rheumatoid arthritis (RA) may exacerbate sarcopenia from physical inactivity because of foot pain while walking. The present study aimed to investigate the prevalence of sarcopen...

Aim: Physical activity benefits health, whereas physical inactivity increases the risk of age‐related conditions and adverse health outcomes. Kyotango City in Japan is known for its residents' longevity, and many centenarians live there. This study investigated the physical activity associations with physical function and body composition in older adults living in this area. Methods: Community‐dwelling older adults ( n = 727; mean age 74.1 years; 59.4% women) participated in this study. Multiple linear regression analyses were carried out to examine objectively‐measured physical activity associations with physical function (handgrip strength, knee extension strength and maximum gait speed) and body composition (skeletal muscle mass index and whole‐body phase angle), adjusting for potential confounders. Additionally, isotemporal substitution models were applied to estimate changes resulting from replacing sedentary behavior with light‐intensity physical activity (LPA) and moderate‐to‐vigorous‐intensity physical activity (MVPA). Results: All physical function and body composition indicators were significantly associated with SB and MVPA (all P < 0.050). However, LPA was associated with only handgrip strength and body composition indicators. Replacing 30 min of SB per day with LPA was associated with a 0.176 kg increase in handgrip strength, 0.018 kg/m ² increase in skeletal muscle mass index and 0.016° increase in whole‐body phase angle. Alternatively, replacing sedentary behavior with MVPA improved all physical function and body composition indicators. Conclusions: Older adults in a region of Japan known for longevity might maintain physical function and favorable body composition through engaging in abundant physical activity. Public health strategies should prioritize MVPA promotion while recognizing LPA's complementary role for physically inactive older adults. Geriatr Gerontol Int 2025; 25: 1511–1517 .

[Purpose] Belt electrode-skeletal muscle electrical stimulation (B-SES) is a novel electrical muscle stimulation treatment that causes less pain and discomfort and induces contraction in a wider skeletal muscle area than conventional electrodes. However, the stimulation intensity depends on patients’ subjectivity. In the present study, B-SES and an expiratory gas device were combined to analyze the kinesiophysiological data associated with changes in subjective intensity. [Participants and Methods] Seventeen healthy participants were recruited. The subjective intensities were set to four conditions (weak, normal, strong, and maximum tolerated intensity), and the stimulation was performed in each condition in the “metabolic mode” (frequency, 4 Hz; pulse width, 250 µs). The primary outcome was metabolic equivalents (METs), and this data were compared for each condition. [Results] METs generated by B-SES were 2.0 (1.0) for weak intensity, 2.7 (1.2) for normal intensity, 3.9 (1.3) for strong intensity, and 5.0 (1.3) for the tolerance limit intensity; differences detected between all subjective intensities were statistically significant. [Conclusion] These findings show that objective intensities of >3 METs, as recommended in rehabilitation prescriptions, can be achieved when the subjective intensity is set at strong or maximum tolerated. Treatment with B-SES may provide a viable alternative to therapeutic exercise.

Background/Objectives: Daily movement behaviors are interdependent within a 24 h period. This study examined associations between 24 h movement behavior composition and muscle-related outcomes and estimated the effect of reallocating time to moderate-to-vigorous physical activity (MVPA) based on these outcomes. Methods: A total of 808 community-dwelling older adults from the Kyotango Longevity Cohort Study were included in this cross-sectional study. Waking behaviors (sedentary behavior, light-intensity physical activity, and MVPA) and sleep were assessed using accelerometers and sleep diaries. Daily time spent performing each behavior was averaged using the compositional mean to create a 24 h composition. Compositional data analysis and Firth’s penalized logistic regression were used to examine associations between movement behavior composition and muscle-related outcomes (low muscle strength, low muscle mass, and sarcopenia defined by the Asian Working Group for Sarcopenia 2025 criteria). Compositional isotemporal substitution analyses were performed to estimate time reallocations toward MVPA. Results: A higher relative contribution of MVPA was associated with lower odds of low muscle strength (odds ratio, 0.67; 95% confidence interval, 0.48–0.93; p = 0.016) and body mass index-adjusted low muscle mass (odds ratio, 0.81; 95% confidence interval, 0.66–0.99; p = 0.042). No associations were observed for height-adjusted low muscle mass and sarcopenia. Reallocating time from other waking activities toward MVPA was associated with lower odds of these outcomes, whereas no significant associations were observed for reallocations from sleep. Conclusions: A higher relative contribution of MVPA was associated with lower odds of low muscle strength and BMI-adjusted low muscle mass. Small reallocations of time from other waking activities toward MVPA may maintain muscle health in older adults.