Author(s): HONDA, A., NAKAJIMA, D., Institution: ASAHI UNIVERSITY, Country: JAPAN, Abstract-ID: 539

INTRODUCTION:
Community-based exercise programs are widely implemented to promote healthy ageing by preserving skeletal muscle mass, physical function, and bone health in older adults.
This study aimed to examine 1-year changes in body composition, functional fitness, and bone density in older females participating in a community exercise program and considered implications for program design.
METHODS:
Thirteen Japanese females aged ≥70 years (mean age 75.5 ± 3.5 years) who regularly attended community exercise classes were included. Participants attended the program at least once weekly, with sessions lasting approximately 60 minutes, and had participated continuously for several years. Each session comprised a 15-minute warm-up involving dynamic stretching and dual-task exercises, followed by 15 minutes of circuit training that combined strength training, rhythmic exercise with aerobic components, and dual-task cognitive activities. The final 15 minutes focused on lower-limb strength training while engaging the trunk and upper limbs to challenge balance. After these exercises, a 10-minute cool-down was performed. Standing exercises were performed only during the warm-up and part of the final lower-limb strength training.
Body weight, body mass index (BMI), lean body mass (LBM), and skeletal muscle mass index (SMI) were assessed. Functional fitness was evaluated using grip strength (GS), sit-and-reach flexibility, the two-step test, whole-body reaction time (RT), the timed up-and-go test (TUG) at maximal speed, the five-repetition sit-to-stand test (5STS), and single-leg standing with eyes open. Bone stiffness (BS) and age-matched percentage values were assessed using quantitative ultrasound of the calcaneus. Measurements were conducted at baseline and after 1 year, and paired t-tests were applied.
RESULTS:
Body weight, BMI, and LBM showed significant reductions over 1 year (p < 0.05), whereas SMI was maintained. Sit-and-reach flexibility, single-leg standing time (both p < 0.05), and 5STS performance (p < 0.01) improved significantly. Performance on the TUG, two-step test, and RT was maintained, with no significant decline. GS demonstrated a non-significant downward trend (p = 0.064). BS showed no significant change, indicating preservation of bone status. Age-matched percentage values averaged approximately 120 %, indicating that bone status was relatively high for age.
CONCLUSION:
Despite its low-to-moderate intensity, this community exercise program contributed to the maintenance or improvement of functional fitness and bone health in older females. By targeting muscle strength, neuromuscular control, and balance, the program may have exerted both direct and indirect benefits on skeletal health, including potential reductions in fall risk and fracture risk.