Effect of Excessive Screen Time on Cardiorespiratory Fitness in Children: A Longitudinal Study.

BACKGROUND: This study investigated the effect of different components of screen time (mobile phone use, TV/video viewing, and video gaming) on cardiorespiratory fitness (CRF) development in children aged 9-12 years. METHODS: This was a two-year longitudinal study conducted with 175 children (49.7% girls, mean age = 9.5) in Japan. CRF was assessed using a 20 m shuttle run test conducted at baseline and again at follow-up. Children were categorized as "Good" or "Poor" based on the change in CRF scores for each gender. Screen time was assessed using a self-reported questionnaire at baseline and termed as "high" if children reported ≥ 2 h/day. Univariate and multivariate logistic regression analyses were performed after adjusting for gender, physical activity, and time of data collection. RESULTS: Children scoring "high" on mobile phone use had lower odds of being categorized as "Good" in CRF change (crude odds ratio (OR): 0.34; 95% confidence interval (CI): 0.15-0.90 (adjusted OR: 0.33; 95% CI: 0.12-0.91)). There were no significant effects of TV/video viewing (crude OR: 1.54; 95% CI: 0.84-2.81) and video gaming (crude OR: 0.98; 95% CI: 0.48-1.97) on changes in CRF. CONCLUSIONS: Limiting excessive mobile phone usage might be important for ensuring healthy development of CRF in children.

Frequency of working at home, body mass index, and productivity in Japanese office workers: A cohort study.

BACKGROUND: Since the start of the COVID-19 pandemic, the number of people working at home has grown significantly. OBJECTIVE: This cohort study aimed to investigate whether the frequency of working at home was associated with changes in body mass index (BMI) and productivity from 2018 to 2020. METHOD: Frequency of working at home was self-reported. Participants were classified into three groups based on mean frequency of working at home per week (no working at home: ≦ 0.5 days, low frequency: 0.5 to 2.5 days, and high frequency: >2.5 days). Productivity was measured using a numerical rating scale, and BMI was calculated using height and weight. Changes in BMI and productivity were calculated by subtracting 2018 data from 2020 data. Linear regression analysis was performed by considering BMI and productivity change as outcomes and frequency of working at home as explanatory variable. RESULTS: BMI change in the high frequency group was significantly smaller than in the group that did not work at home (crude; coefficient: -0.27; 95% CI: -0.55--0.01, adjusted; coefficient: -0.30; 95% CI: -0.60--0.01). Frequency of working at home was not associated with productivity change. CONCLUSION: Working at home may be a solution for preventing BMI from increasing significantly.

Association Between Workplace Social Capital and Neck Pain: A Cross-Sectional Study Among Workers.

OBJECTIVE: We examined the association between workplace social capital (WSC) and presence of neck pain (NP) among workers. METHODS: This cross-sectional study included 595 workers. Presence of NP was assessed using Numerical Rating scale. WSC (overall, bonding, bridging, and linking) was divided into three categories (low, middle, and high) based on tertile distributions. We used logistic regression analysis to investigate the association between WSC and presence of NP. RESULTS: Low overall, bonding, and linking social capital were significantly associated with presence of NP in comparison with each high social capital (overall: adjusted odds ratio [aOR] = 1.76, 95% confidence interval [CI] = 1.14 to 2.73; bonding: aOR = 1.78, 95% CI = 1.19 to 2.67, linking: aOR = 2.18, 95% CI = 1.32 to 3.63). CONCLUSION: Lower WSC had an association with higher prevalence of NP among workers.

Association Between Abrupt Change to Teleworking and Physical Symptoms During the Coronavirus Disease 2019 (COVID-19) Emergency Declaration in Japan.

OBJECTIVE: We investigated the association between telework frequency and the presence of non-COVID-19-related physical symptoms during the COVID-19 emergency declaration among workers in Japan. METHODS: Data were collected from 1648 workers via web-based self-reported questionnaires. Multivariate logistic regression models were used to investigate the association between telework frequency per week (0, 1-2, 3-4, and ≥5 days/week) and the presence of stiff shoulders, eyestrain, and low back pain. RESULTS: Among 917 participants, telework frequency was significantly associated with stiff shoulders (≥5 days: adjusted odds ratio [aOR] 3.02, 95% confidence interval [CI] 1.37-7.06), eyestrain (≥5 days: aOR 5.31, 95% CI 2.09-13.44), and low back pain (≥5 days: aOR 5.57, 95% CI 2.22-14.00), compared with non-teleworkers. CONCLUSIONS: Workers who abruptly began telework experienced more physical symptoms than non-teleworkers during the emergency declaration.