Departmental Bulletin Paper

Reduced hand grip strength has been associated with an increased risk of lifestyle related diseases including cardiovascular mortality, certain types of cancer, and dementia. Grip strength is appealing as a simple, quick, and inexpensive means of stratifying an individualʼs risk of health issues. Dementia has been one of the biggest causes of health issues in Japanese society. However, the effective exercise program for grip strength with respect to research studies is unknown. The aim of this study was to investigate the effectiveness of hand ball activity in older Japanese adults, especially for improving their cognitive function and hand grip strength. Ten older adults, aged 72 to 90 years (mean age 79 years, SD ±5.94), were randomly selected. Cognitive function was evaluated by the MINI-Cog test. Hand dexterity, muscle strength, balance, flexibility were defined as physical performances. Participantsʼ data were analyzed by a Wilcoxon rank sum test, Pearson product-moment correlation coefficient, and the forward-backward stepwise test. For 12 weeks between April 1, 2022 to July 1, 2022 the exercise program was implemented. The subjects participated in a 60 minutes class once a week. Each class was composed of 3 parts of ball activity such as 1) a muscle strengthening exercise, 2) hand dexterity exercises, and 3) Throwing and catching exercises once a week. As for the results, subjects showed significantly higher scores for the hand grip strength (average improving ratio; 0.918kg, SD ±3.85, p＜0.016). There is no significance with other tests however, subjects showed higher scores for hand finger motion test (average improving ratio; 1.0, SD ±5.4), and functional reach test (average improving ratio; 1.39cm, SD ±5.5). We found no significant associations between hand ball activity and cognitive skills with the MINI-Cog test. This study suggests that hand ball activity is an easy, inexpensive, simple daily exercise method for improving grip strength in older adults. Further research is needed to identify determinants of muscular strength, hand dexterity, and to test whether improvement in strength reduces mortality, cardiovascular disease, and dementia.