Voluntary stand-up physical activity enhances endurance exercise capacity in rats

Involuntary physical activity induced by the avoidance of electrical shock leads to improved endurance exercise capacity in animals. However, it remains unknown whether voluntary stand-up physical activity (SPA) without forced simulating factors improves endurance exercise capacity in animals. We examined the eff ects of SPA on body weight, cardiac function, and endurance exercise capacity for 12 weeks. Twelve male Sprague-Dawley rats (aged 8 weeks, n=6 per group) were randomly assigned to a control group (CON) or a voluntary SPA group. The rats were induced to perform voluntary SPA (lifting a load equal to their body weight), while the food height (18.0 cm) in cages was increased progressively by 3.5 every 4 weeks until it reached 28.5 cm for 12 weeks. The SPA group showed a lower body weight compared to the CON group, but voluntary SPA did not affect the skeletal muscle and heart weights, food intake, and echocardiography results. Although the SPA group showed higher grip strength, running time, and distance compared to the CON group, the level of irisin, corticosterone, genetic expression of mitochondrial biogenesis, and nuclei numbers were not affected. These findings show that voluntary SPA without any forced stimuli in rats can eff ectively reduce body weight and enhance endurance exercise capacity, suggesting that it may be an important alternative strategy to enhance endurance exercise capacity.

Empirical Analysis of Supplier Induced Demand in Korea: Distinction between Induced Demand Effect and Availability Effect / 보건행정학회지

BACKGROUND: Supplier induced demand (SID) indicates the case when doctors increase the demand of the patients, following their (physicians') own best interests rather than patients'. This may occur when asymmetry of information exists between suppliers and consumers. This study aims to confirm whether SID exists in the Korean setting, particularly by dividing SID into both 'induced demand effect' and 'availability effect.' METHODS: Induced demand effect and availability effect are differentiated following Carlsen & Grytten's theoretical frame which divides doctor density regions into high and low ones. RESULTS: Positive correlation between doctors' density and utilization of their services was found, which could be interpreted as 'availability effect.' CONCLUSION: The result suggests that additional medical use for additional doctor, particularly in the area of low doctor density, can be interpreted to occur to meet the basic medical need of the people rather than as a result of unnecessary induced demand. It is important to make more medical doctors provided and to distribute them appropriately across the region in such a country like Korea where doctor's density is relatively low.

Factors Associated with Early Smoking Initiation among Korean Adolescents

PURPOSE: The aim of this study was to identify factors associated with early initiation of cigarette smoking among Korean adolescents. METHODS: A secondary analysis was conducted on the 2012 Korea Youth Risk BehaviorWeb-based Survey data using Cox proportional hazards regression. RESULTS: Early smoking initiation was associated with being male, having a positive subjective health status, perceiving oneself as thin or average weight (body image), having an average happiness level, being stressed, consuming alcohol, having suicidal ideation, experiencing sexual intercourse, having low or average academic grades, having a parental education level of high school or below, not taking a family trip in the previous 12 months, and having a family that approves of smoking in the home. CONCLUSIONS: Interventions targeting the prevention of smoking initiation among adolescents should include individual factors such as health status, body weight, perceived mental health status, health-risk behaviors, and academic characteristics as well as family factors that reinforce family cohesion and home smoking bans. Moreover, male adolescents aged 12e13 years and their parents should be the main target of these interventions.

Relationship between Health Status and Life Styles and Atopic Dermatitis in Adolescents

PURPOSE: The aim was to explore the relationship between health status/life style and prevalence of atopic dermatitis in adolescents. METHODS: Data from 1,743 adolescents (aged 13 to 18 years) derived from the fourth Korea National Health and Nutrition Examination Survey (KNHANES) were analyzed using binary logistic regression and the classification and regression tree (CART) model. RESULTS: The prevalence rate of atopic dermatitis was 10.3%. Third quartile income class (OR=2.19, 95% CI=1.20-4.00), fair and unhealthy self-rated health (OR=1.49, 95% CI=1.06-2.11; OR= 2.73, 95% CI=1.64-4.55), past or current smoker (OR=0.41, 95% CI=0.20-0.85; OR=0.44, 95% CI=0.21-0.92), and more than average stress (OR=1.43, 95% CI=1.03-1.99) were related with increased prevalence of atopic dermatitis. The high prevalence risk groups for atopic dermatitis were adolescents who perceived themselves to be healthy on self-rated health and had more than average stress and those who perceived themselves to be unhealthy and who never smoked. CONCLUSION: The results of the study indicate that health status, smoking, and stress are associated with a prevalence risk for adolescent atopic dermatitis in different degrees. Therefore, for control of atopic dermatitis, various interventions for smoking and stress need to be reinforced for the high prevalence atopic dermatitis groups.