Objectives: Excessive sedentary behavior in youth is a major global issue, contributing to the rise in childhood obesity and metabolic diseases. International public health authorities have issued guidelines recommending that children and adolescents limit their daily sedentary time, including screen time. However, to date, no studies have explored the relationship between sedentary behavior as an exposure factor and skeletal muscle strength and mass as outcomes in this population. The present study investigated the association of sedentary behavior with handgrip strength (HGS) and appendicular lean mass (ALM) among United States adolescents. Methods: A total of 1449 adolescent participants from the National Health and Nutrition Examination Survey (2011-2014) were included. Information on sedentary behavior, specifically daily sedentary time, was obtained through a self-reported questionnaire. Muscular parameters, including HGS and ALM, were measured. To adjust for differences in body size, these parameters were divided by body mass index (BMI) and weight. Linear regression analyses were performed to evaluate the associations between daily sedentary time and each muscular parameter, adjusting for age, sex, ethnicity, annual family income, and moderate-to-vigorous physical activity (MVPA). Results: The linear regression analyses revealed negative associations between daily sedentary time and all muscular parameters, apart from absolute ALM. These included HGS (β, -0.265; standard error [SE], 0.074; p=0.001), HGS/BMI (β, -0.021; SE, 0.004; p<0.001), HGS/weight (β, -0.008; SE, 0.002; p<0.001), ALM/BMI (β, -0.008; SE, 0.003; p=0.010), and ALM/weight (β, -0.003; SE, 0.001; p=0.005). Conclusions After adjusting for MVPA, daily sedentary time was inversely associated with HGS, HGS/BMI, HGS/weight, ALM/BMI, and ALM/weight in United States adolescents.

Objectives: Excessive sedentary behavior in youth is a major global issue, contributing to the rise in childhood obesity and metabolic diseases. International public health authorities have issued guidelines recommending that children and adolescents limit their daily sedentary time, including screen time. However, to date, no studies have explored the relationship between sedentary behavior as an exposure factor and skeletal muscle strength and mass as outcomes in this population. The present study investigated the association of sedentary behavior with handgrip strength (HGS) and appendicular lean mass (ALM) among United States adolescents. Methods: A total of 1449 adolescent participants from the National Health and Nutrition Examination Survey (2011-2014) were included. Information on sedentary behavior, specifically daily sedentary time, was obtained through a self-reported questionnaire. Muscular parameters, including HGS and ALM, were measured. To adjust for differences in body size, these parameters were divided by body mass index (BMI) and weight. Linear regression analyses were performed to evaluate the associations between daily sedentary time and each muscular parameter, adjusting for age, sex, ethnicity, annual family income, and moderate-to-vigorous physical activity (MVPA). Results: The linear regression analyses revealed negative associations between daily sedentary time and all muscular parameters, apart from absolute ALM. These included HGS (β, -0.265; standard error [SE], 0.074; p=0.001), HGS/BMI (β, -0.021; SE, 0.004; p<0.001), HGS/weight (β, -0.008; SE, 0.002; p<0.001), ALM/BMI (β, -0.008; SE, 0.003; p=0.010), and ALM/weight (β, -0.003; SE, 0.001; p=0.005). Conclusions After adjusting for MVPA, daily sedentary time was inversely associated with HGS, HGS/BMI, HGS/weight, ALM/BMI, and ALM/weight in United States adolescents.

Objectives: Excessive sedentary behavior in youth is a major global issue, contributing to the rise in childhood obesity and metabolic diseases. International public health authorities have issued guidelines recommending that children and adolescents limit their daily sedentary time, including screen time. However, to date, no studies have explored the relationship between sedentary behavior as an exposure factor and skeletal muscle strength and mass as outcomes in this population. The present study investigated the association of sedentary behavior with handgrip strength (HGS) and appendicular lean mass (ALM) among United States adolescents. Methods: A total of 1449 adolescent participants from the National Health and Nutrition Examination Survey (2011-2014) were included. Information on sedentary behavior, specifically daily sedentary time, was obtained through a self-reported questionnaire. Muscular parameters, including HGS and ALM, were measured. To adjust for differences in body size, these parameters were divided by body mass index (BMI) and weight. Linear regression analyses were performed to evaluate the associations between daily sedentary time and each muscular parameter, adjusting for age, sex, ethnicity, annual family income, and moderate-to-vigorous physical activity (MVPA). Results: The linear regression analyses revealed negative associations between daily sedentary time and all muscular parameters, apart from absolute ALM. These included HGS (β, -0.265; standard error [SE], 0.074; p=0.001), HGS/BMI (β, -0.021; SE, 0.004; p<0.001), HGS/weight (β, -0.008; SE, 0.002; p<0.001), ALM/BMI (β, -0.008; SE, 0.003; p=0.010), and ALM/weight (β, -0.003; SE, 0.001; p=0.005). Conclusions After adjusting for MVPA, daily sedentary time was inversely associated with HGS, HGS/BMI, HGS/weight, ALM/BMI, and ALM/weight in United States adolescents.

The prevalence of multiple job-holding (MJH) is expected to show an upward trend among Korean workers, yet its potential impact on workers’ health remains poorly discussed. This study aimed to explore the association between MJH and experience of physical and psychological symptoms in various aspects among active Korean workers and to identify its differences depending on workers’ gender.

The coronavirus disease 2019 (COVID-19) pandemic drastically modified the occupational system wherein telecommuting has risen as the major form of work. Few studies have incorporated Karasek’s job demand-control (JDC) model into explaining the health effects of telecommuting. This study aimed to investigate the health risk in South Korean telecommuters during the pandemic, and its distribution according to the job stress-related factors.

The prevalence of multiple job-holding (MJH) is expected to show an upward trend among Korean workers, yet its potential impact on workers’ health remains poorly discussed. This study aimed to explore the association between MJH and experience of physical and psychological symptoms in various aspects among active Korean workers and to identify its differences depending on workers’ gender.

The coronavirus disease 2019 (COVID-19) pandemic drastically modified the occupational system wherein telecommuting has risen as the major form of work. Few studies have incorporated Karasek’s job demand-control (JDC) model into explaining the health effects of telecommuting. This study aimed to investigate the health risk in South Korean telecommuters during the pandemic, and its distribution according to the job stress-related factors.

The prevalence of multiple job-holding (MJH) is expected to show an upward trend among Korean workers, yet its potential impact on workers’ health remains poorly discussed. This study aimed to explore the association between MJH and experience of physical and psychological symptoms in various aspects among active Korean workers and to identify its differences depending on workers’ gender.

The coronavirus disease 2019 (COVID-19) pandemic drastically modified the occupational system wherein telecommuting has risen as the major form of work. Few studies have incorporated Karasek’s job demand-control (JDC) model into explaining the health effects of telecommuting. This study aimed to investigate the health risk in South Korean telecommuters during the pandemic, and its distribution according to the job stress-related factors.

Objectives: Adolescents who engage in unhealthy behaviors are particularly vulnerable to anxiety. We hypothesized that participation in physical activity could influence the relationship between anxiety and unhealthy behaviors in adolescents. These behaviors include smoking, alcohol consumption, and unsafe sexual activity. Methods: This study included 50 301 students from the first year of middle school to the third year of high school, all from Korea. The unhealthy adolescent behaviors examined included current alcohol consumption, current smoking, and unsafe sexual behavior. Anxiety levels were assessed using the Generalized Anxiety Disorder-7 questionnaire (GAD-7). Results: The participants had a mean age of 15.19 years and an average GAD-7 score of 4.23. No significant differences were observed in GAD-7 score among exercising participants when categorized by smoking status (p=0.835) or unsafe sexual behavior (p=0.489). In contrast, participants in the non-exercise group who engaged in these behaviors demonstrated significantly higher GAD-7 scores (p<0.001 and 0.016, respectively). The only significant interaction was found between unsafe sexual behavior and exercise (p=0.009). Based on logistic regression analysis, within the non-exercise group, significant positive associations were observed between current smoking and anxiety (odds ratio [OR], 1.36; 95% confidence interval [CI], 1.18 to 1.57), as well as between unsafe sexual behavior and anxiety (OR, 1.33; 95% CI, 1.02 to 1.73). However, within the exercise group, no significant association was found between anxiety and either smoking or unsafe sexual behavior. Furthermore, no significant interaction was observed between unhealthy behaviors and exercise. Conclusions These findings are insufficient to conclude that physical activity influences the relationship between unhealthy behaviors and anxiety.