Author(s): NOSAKA, K., TAGUCHI, T., SATO, S., NAKAMURA, M., Institution: EDITH COWAN UNIVERSITY, Country: AUSTRALIA, Abstract-ID: 283

INTRODUCTION:
Bodyweight resistance exercise training focusing on eccentric contractions (bodyweight eccentric exercise training) is effective for improving muscle and physical functions in older adults [1] as well as in sedentary individuals [2]. Considering its simplicity, sustainability and cost-effectiveness of bodyweight eccentric exercises, it is crucial to evaluate its long-term effects on health and physical function parameters. However, most of the studies in which bodyweight eccentric exercise effects were investigated was short in its intervention duration (4-8 weeks). It might be that the effects of bodyweight eccentric exercise are leveling off or even attenuated when it is continued for a longer period. Therefore, the present study investigated the effects of less than 10-minute body weight eccentric exercise training performed once a week for one year by community-dwelling elderly women on some health, body composition, and physical function parameters.
METHODS:
Twenty-seven elderly (65-88 y; average±SD: 78.4±6.5 y) women participated in an exercise program focusing on bodyweight eccentric exercises held at a community center once a week for one year, and the total number of exercise sessions that they participated was 43-50. The exercises included chair squat, chair recline, heel drop, and knee down [1] in which slow (3-seconds) eccentric contraction followed by minimal effort concentric contraction (1-second) were performed in each movement. All exercises consisted of 1 set of 10 repetitions, and at least 1-minute of rest was inserted between exercises. Outcome measures included body mass index (BMI), skeletal muscle mass index (SMI) and phase angle by bioimpedance method, resting heart rate, systolic and diastolic blood pressure, grip strength, and 6-meter maximal walking speed. These were measured before and after the one-year exercise intervention, and changes were analyzed by paired t-test.
RESULTS:
No significant changes in BMI (baseline: 21.8±3.7 kg/m2), resting heart rate (73.1±7.3 bpm), systolic (125.6±10.0 mmHg) and diastolic blood pressure (68.7±7.2 mmHg) were observed from baseline to one-year later. Significant (P<0.05) changes in grip strength (pre: 19.9±4.6 – post: 20.9±4.7 kg; change: 5.6±8.9%), maximal walking speed (1.20±0.18 – 1.29±0.16 m/s; 8.3±11.4％), SMI (6.33±0.51 – 6.55±0.62; 3.5±6.3%), and phase angle of both legs (3.88±0.88° – 4.15±0.84°; 8.7±16.3%) from pre- to post-intervention were evident. Importantly, no participants showed any negative effects of the intervention.
CONCLUSION:
In older adults, physical function declines over a year; however, the results of the study suggest that continuing the low dose bodyweight eccentric exercise once a week is still effective for improving or at least maintaining motor function and skeletal muscle quality.

[1] Katsura et al. Eur J Appl Physiol. 119:1581-90, 2019.
[2] Kirk et al. Eur J Appl Physiol. 125:2241-55, 2025.