We clarified the relationship between occupational dysfunction and social isolation among community-dwelling adults. We used a self-administered questionnaire with a cross-sectional study for 2879 independently living older adults in Kasama City, Japan. Participants responded to a self-reported questionnaire in November 2019. Occupational dysfunction and social isolation were assessed. The participants were classified into two groups: healthy occupational function group, and occupational dysfunction group. To examine the relationship between occupational dysfunction and social isolation, we performed a logistic regression analysis with social isolation as a dependent variable and occupational dysfunction as an independent variable. In the crude model, the occupational dysfunction group had a higher risk of social isolation than the healthy occupational function group (odds ratio (OR) = 2.04; 95% confidence interval (CI), 1.63–2.55; p < 0.001). In the adjusted model, the occupational dysfunction group had a higher risk of social isolation than the healthy occupational function group (OR = 1.51; 95% CI, 1.17–1.94; p = 0.001). The results showed that occupational dysfunction was significantly associated with social isolation. These results can be used in constructing a support method for social isolation from a new perspective.

Objectives: Frailty might be useful to identify older drivers who are at risk for traffic crashes. We aim to examine the association between pre-frailty/frailty defined by the Kihon Checklist (KCL) and the involvement of traffic crashes and clarify whether some domains of the KCL are associated with traffic crashes. Methods: This cross-sectional study analyzed data from 2,208 Japanese community-dwelling older drivers aged ≥ 65 years in Kasama City, who participated in our postal survey in November 2019. A self-reported history of traffic crashes was used to divide participants into non-crash-involved and crash-involved groups. Results: A total of 192 (8.7%) participants had been involved in traffic crashes in the past year. The crash-involved group was found to have gained more body mass index, driven more frequently, and scored higher on the total KCL score than the non-crash-involved group (all P < .05). Binary logistic regression analyses showed that after adjusting for age, sex, education, driving frequency, and driving distance, pre-frailty (OR = 1.52, 95% CI: 1.10–2.10) was more significantly associated with traffic crashes as compared to robustness. Those who had impairment in the oral domain (OR = 1.57, 95% CI: 1.09–2.27) and memory domain (OR = 1.38, 95% CI: 1.01–1.90) were also more likely to be involved in traffic crashes. Conclusion: The results suggest that identifying pre-frailty may play an important pole in crash prevention. Additionally, more attention should be given to older drivers with oral dysfunction and cognitive impairment.

Caffeine, widely used as an ergogenic aid, has been extensively studied regarding its dosage and timing of ingestion. However, the impact of different administration methods on caffeine's performance-enhancing effects remains relatively underexplored. This study compared the effects of caffeine administered via chewing gum versus capsules on maximal strength, muscular power, and side effects during bench press and back squat exercises. Sixteen resistance-trained males participated in a double-blind, randomized trial, ingesting either a 4 mg/kg caffeine capsule (CC) or placebo capsule (PC) one hour before testing, or a 4 mg/kg caffeinated gum (CG) (4 mg/kg) or placebo gum (PG) five minutes prior. Assessments including one-repetition maximum (1RM) and muscular power at 25%, 50%, 75%, and 90%1RM for bench press and back squat. Caffeine increased 1RM (+2.1-5.0%) and muscular power (+6.1-20.0%) in both the bench press and back squat compared to placebo (all p < 0.05). However, no significant differences were observed between CC and CG for maximal strength or muscular power (all p > 0.05). Furthermore, CG was associated with fewer reports of gastrointestinal discomfort (12.5% vs. 37.5%) immediately post-exercise and tachycardia/heart palpitations (0% vs. 25.0%) at 24 hours compared to CC (all p < 0.05). Caffeinated gum (4 mg/kg) produced ergogenic effects comparable to capsules in enhancing maximal strength and muscular power during bench press and back squat exercises, with fewer side effects in resistance-trained men.

The purpose of this cross-sectional study was to clarify the relationship between frailty/occupational dysfunction (OD), both with and without, and subjective well-being among community-dwelling older adults. A total of 2308 (average age: 72.2 ± 5.1, female: 47.0%) independently living older adults in Kasama City, Japan, completed a self-administered questionnaire in November 2019. OD, frailty, and subjective well-being were assessed. Participants were classified into six groups: robust and healthy occupational function (HOF), robust and OD, pre-frail and HOF, pre-frail and OD, frail and HOF, and frail and OD. To examine the relationship between frailty/OD and subjective well-being, we performed an analysis of variance with subjective well-being as the dependent variable and with and without frailty/OD (six groups) as the independent variables. The results showed a significant association between with and without frailty/OD and subjective well-being in community-dwelling older adults. The subjective well-being of the pre-frail and HOF group was significantly better than that of the robust and OD group. Furthermore, the subjective well-being of the frail and HOF group was significantly better than that of the pre-frail and OD group. These results can be used to develop a new support method for frailty.