This cross-sectional study aimed to examine the association of various aspects of physical activity, including intensity, duration, type, and purpose, with the phase angle (PhA), an objective indicator of health, in Korean adults after stratification by sex. Data from the 2022 Korean National Health and Nutrition Examination Survey, a nationwide, representative, population-based survey, were used. In total, 3996 participants were included in the study. Participants self-reported their weekly intensity, frequency, duration of engagement in physical activity. PhA was categorized into two groups on the basis of sex-specific averages. Multiple logistic regression analysis was used to investigate the relationship between physical activity and PhA, and proportional odds logistic regression analysis was performed to determine the association between physical activity and different subclasses of PhA. A positive association was found between sufficiently active aerobic physical activity and PhA compared with inactive physical activity (sufficiently active, male: odds ratio = 1.952, 95% confidence interval = 1.373–2.776; female: odds ratio = 1.333, 95% confidence interval = 1.019–1.745). This association was further strengthened when aerobic physical activity was accompanied by muscle-strengthening activity (sufficiently active with muscle-strengthening activity, male: aOR = 2.318, 95% CI = 1.512–3.554; female: aOR = 1.762, 95% CI = 1.215–2.556) and vigorous-intensity activities (sufficiently active with sufficient vigorous-intensity activity, male: aOR = 2.785, 95% CI = 1.647–4.709; female: aOR = 2.505, 95% CI = 1.441–4.356) and when there was more leisure-time physical activity than occupational physical activity (sufficiently active with more leisure-time physical activity, male: aOR = 2.158, 95% CI = 1.483–3.140; female: aOR = 1.457, 95% CI = 1.078–1.969). Furthermore, the inclusion of muscle-strengthening activity made a significant difference in the values of PhA for males with insufficiently active physical activity (aOR = 2.679, 95% CI = 1.560–4.602). For females with highly active physical activity (aOR = 1.521, 95% CI = 1.068–2.166), the inclusion of muscle-strengthening and vigorous-intensity activities were significantly associated with higher values for PhA. This study can be utilized to provide specific suggestions for better health programs and can change perception that only occupational physical activity is enough. This study also indicated that PhA can be used for personalized health assessments.
Changes in land-use type can affect soil and water properties in stream ecosystems. This study examined the effects of different land-use types on biogeochemical properties and microbial activities of a stream. We collected water and sediment samples in a stream at three different sites surrounded by varying land-use types; a forest, a radish field and a rice paddy. Nitrogen contents, such as nitrate, nitrite and total nitrogen in the stream water body, showed significant differences among the sampling sites. The highest nitrogen values were recorded at the site surrounded by cropland, as fertilizer runoff impacted the stream. Soil organic matter content in the sediment showed significant differences among sites, with the highest content exhibited at the forest mouth site. These differences might be due to the organic matter in surrounding terrestrial ecosystems. Microbial activities determined by extracellular enzyme activities showed similar values throughout all sites in the water body; however, the activities in the sediments exhibited the highest values near the forest site and mirrored the soil organic matter content values. From these results, we conclude that different land-use types are important factors affecting water and sediment properties in stream ecosystems.
Northern peatlands are substantial carbon sinks because organic matter in peat is highly stable due to the low rate of decomposition. Waterlogged anaerobic conditions induce accumulation of Sphagnum -derived phenolic compounds that inhibit peat organic matter decomposition, a mechanism referred to as the “enzymic latch”. Recent studies have predicted that the water table in northern peatlands may become unstable. We observed that such unstable water table levels can impede the development of Sphagnum mosses. In this study, we determined the effects of low and high frequency water table fluctuation regimes on Sphagnum growth and peat organic matter decomposition, by conducting a year-long mesocosm experiment. In addition, we conducted a molecular analysis to examine changes in abundance of fungal community which may play a key role in the decomposition of organic matter in peatlands. We found that rapid water table fluctuation inhibited the growth of Sphagnum due to fungal infection but stimulated decomposition of organic matter that may dramatically destabilize peatland carbon storage. Increased pH, induced by the fluctuation, may contribute to the enhanced activity of hydrolases in peat. We demonstrated that the water table fluctuation in peatlands impeded Sphagnum growth and accelerates decomposition due to fungal proliferation. Thus, we suggested that understanding the microbial community in the northern peatlands is essential for elucidating the possible changes in carbon cycle of peatland under the changing world.
Objectives: A campus-based intervention to enhance food literacy (FL) and establish exercise habits among college students was developed and the program’s effectiveness was evaluated. Methods: The 13-session program was developed based on the transtheoretical model and social cognitive theory. Junior and senior students majoring in food and nutrition and physical education were asked to participate as mentors, with freshmen and sophomores from varied majors as mentees. The program encompassed food, nutrition, and exercise lessons including cooking sessions. Data were collected via pre- and post-program surveys using a questionnaire consisting of items on FL and nutrition behaviors and physical fitness measurements. Results: Among 39 participants (35.9% male, 64.1% female), the overall FL score increased significantly from 64.1 to 70.6 post-program (P = 0.001). Significant increases were observed in the nutrition and safety (P < 0.001), cultural and relational (P = 0.023), and socio-ecological (P = 0.001) domains, as well as knowledge (P = 0.001), self-efficacy (P = 0.013), attitude (P < 0.001), and behavior (P = 0.005) items in three domains of FL. Additionally, meal duration increased significantly (P = 0.007) and sit-up performance among female showed a meaningful change (P = 0.046). Changes in dietary behaviors significantly progressed (P = 0.015) while that in exercise habits approached a marginal significance (P = 0.053) after the intervention. Conclusion: The results reveal positive changes in FL and some modifications in eating habits, although the program had limited effects on physical activity and fitness measurements. These findings suggest that strategic approaches to foster exercise behavior changes in college students are required. This pilot program can serve as foundational data for improving and expanding multicomponent health promotion programs for this population.
Abstract Background Anxiety disorders are common during adolescence; therefore, detecting anxiety disorders among adolescents and providing appropriate treatment are crucial. Studies have suggested that watching online audiovisual broadcasts like mukbang and cookbang (hereafter mukbang ), where hosts eat or cook food, may influence anxiety disorders. However, there is insufficient research on the association between watching mukbang and generalized anxiety disorder (GAD). Therefore, we investigated the association between watching mukbang and GAD among Korean adolescents. Methods We analyzed 51,764 adolescents who participated in the 2020 Korea Youth Risk Behavior Web-Based Survey (KYRBS). The participants were asked how frequently they watched mukbang per week over the past 12 months. Anxiety disorders were assessed using the generalized anxiety disorder-7 (GAD-7) questionnaire. A multiple logistic regression analysis was performed after adjusting for confounding variables. Results The prevalence of GAD was higher among adolescents who watched mukbang compared to those who did not (aOR: 1.100, 95% CI: 1.026–1.180, P = 0.008 in male participants; aOR: 1.090, 95% CI: 1.003–1.185, P = 0.042 in female participants). The frequency of watching mukbang showed a dose-dependent relationship with a greater likelihood of GAD in female adolescents. Conclusion This study’s results showed that watching mukbang is associated with GAD in Korean adolescents. Proper interventions for mental health are needed for adolescents who watch mukbang.
Soil microorganisms play a pivotal role in regulating the forest C cycle, and responses of forest soil C to climate change depend on their community characteristics. Since recently, climate change and anthropogenic activities–induced forest vegetation shifts are occurring across the globe and substantially affect the forest C cycle. In Northeast Asia, expansion of broadleaf forest and contraction of needleleaf forest has been recently reported and predicted. This vegetation shift can significantly change soil microbial characteristics since broadleaf and needleleaf species have different litter chemistry and physical structure. However, the effects of this shift on forest soil microbial characteristics and consequently on the forest C cycle are yet poorly understood. Here, we monitored soil respiration, extracellular enzyme activities, and edaphic characteristics seasonally for 2 years and microbial community composition, structure, and diversity seasonally for a year in a subtropical forest under different tree species. We also monitored soil respiration and enzyme activities during the growing season in a temperate forest under different tree species. Broadleaf forest showed higher soil respiration and extracellular enzyme activities than needleleaf forest. Distinct soil microbial community composition and structure were found between broadleaf forest and needleleaf forest. Statistical analysis suggested that soil organic matter primarily determines distinct microbial characteristics between broadleaf and needleleaf species. Our results suggest that climate change and anthropogenic activities–induced expansion of broadleaf forest and contraction of needleleaf forest substantially increase overall soil CO2 emission in forests, subsequently inducing positive feedback to climate change.