Association between physical activity and quality of life in Japanese adults aged 85 to 89 years: a cross-sectional study

Background Associations between physical activity (PA) and quality of life (QOL) have usually been studied in people in their 60s and 70s, however little is known about these associations in older age groups. We aimed to examine the association between PA and QOL in Japanese adults aged 85-89 years and investigate the types of exercises/sports in this population. Methods This cross-sectional study (n = 914) used baseline data from the Kawasaki Aging and Well-being Project (KAWP), a longitudinal cohort study of older adults aged 85-89 years. Health-related QOL and psychological well-being were assessed using the EuroQoL 5D-5L (EQ-5D-5L) and the WHO Five Well-Being Index (WHO-5), respectively. PA was objectively and subjectively measured using a triaxial accelerometer and modified Zutphen Physical Activity Questionnaire, respectively. Associations were analyzed using multivariable regression analysis. Results Higher PA was significantly associated with a higher EQ-5D-5L index score (coefficient, 0.004; 95%CI [0.001, 0.008], standardized coefficient, 0.142). In contrast, no association was observed between PA and the WHO-5 total score (coefficient, 0.103; 95%CI [-0.066, 0.271], standardized coefficient, 0.068). Calisthenics were the most commonly performed sports or exercises (27.4% of male and 47.6% of female participants). The subgroup of participants with > median PA had a longer walking duration than their counterparts, and the following sports/exercises were more frequently performed in addition to calisthenics; resistance training and others among male participants: stretching/yoga among female participants. Conclusions Our findings suggest that PA is associated with a better health-related QOL. However, no association was observed between PA and psychological well-being in this population. We found that calisthenics were the most commonly performed and that more physically active older adults performed several types of exercises/sports in addition to calisthenics and walking for longer durations. Since few studies have investigated the types of exercises/sports in this age group, these findings would be helpful for interventions to maintain PA and QOL in this age group. Trial registration UMIN000026053.