Background COVID-19 prevention behaviors have become part of our lives, and they have been reported to be associated with health literacy, knowledge, and fear. However, the COVID-19 pandemic may be characterized by different situations in each age group. Since the severity of the infection and the means of accessing information differ by age group, the relationship between health literacy, knowledge, and fear may differ. Thus, factors that promote preventive behavior may differ by age group. Clarifying the factors related to prevention behaviors by age may help us consider age-appropriate promotion. Objective This study aims to examine the association between COVID-19 prevention behaviors and health literacy, COVID-19 knowledge, and fear of COVID-19 by age group. Methods A cross-sectional study was conducted among 512 participants aged 20-69 years, recruited from a web-based sample from November 1 to November 5, 2021. A web-based self-administered questionnaire was used to obtain the participants’ characteristics, COVID-19 prevention behaviors, health literacy, COVID-19 knowledge, and fear of COVID-19. The Kruskal-Wallis rank sum test was used to compare the scores of each item for each age group. The relationships among COVID-19 prevention behaviors, health literacy, COVID-19 knowledge, and fear of COVID-19 were analyzed using the Spearman rank correlation analysis. Additionally, multiple regression analysis was conducted with COVID-19 prevention behaviors as dependent variables; health literacy, COVID-19 knowledge, and fear of COVID-19 as independent variables; and sex and age as adjustment variables. Results For all participants, correlation and multiple regression analyses revealed that prevention behaviors were significantly related to health literacy, COVID-19 knowledge, and fear of COVID-19 (P<.001). Additionally, correlation analysis revealed that fear of COVID-19 was significantly negatively correlated with COVID-19 knowledge (P<.001). There was also a significant positive correlation between health literacy and COVID-19 knowledge (P<.001). Furthermore, analysis by age revealed that the factors associated with prevention behaviors differed by age group. In the age groups 20-29, 30-39, and 40-49 years, multiple factors, including health literacy, influenced COVID-19 prevention behaviors, whereas in the age groups 50-59 and 60-69 years, only fear of COVID-19 had an impact. Conclusions The results of this study revealed that the factors associated with prevention behaviors differ by age. Age-specific approaches should be considered to prevent infection.

Aims: This study aimed to (1) examine the feasibility of an online interactive exercise class for community-dwelling older adults and (2) preliminarily examine changes in physical activity and self-efficacy. Methods: Participants were 25 community-dwelling older adults aged 65 years or older, but due to 5 dropouts, the final number of participants for analysis was 20 (mean age 76.9 ± 5.7 years). The intervention program was conducted for 40 minutes each session, twice a week for four consecutive weeks, using the LINE group call (LINE Corporation, Japan). An online questionnaire was used to assess participant characteristics, modified Fall Efficacy Scale score, modified Gait Efficacy Scale (m-GES) score, self-rated health, and daily steps, which were compared pre- and post-intervention using the Wilcoxon signed-rank sum and chi-square tests. Results: The Wilcoxon signed-rank sum test showed significant improvement in the m-GES score and daily steps. The chi-square test showed that self-rated health was significantly greater in the maintenance/increase group. Conclusions: Online interactive exercise classes are feasible for community-dwelling older individuals. These results also suggest the possibility of using telehealth to improve physical activity and self-efficacy.