The purpose of the study is to find the impact of social and economic factors in physical activity of children and youth. This study utilized the data from 4th Korean Children and Youth Panel Study(KCYPS), and the analysis were carried out based on the starting sample of 2,009 from ‘the elementary 4 panel’ and 1,978 from the ‘middle school 1 panel’ and 1,984 from the ‘high school 1 panel’, 5,971 full data were used in the final analysis. Data were processed using hierarchical regression analysis and it was statistically validated at the significance level of 0.05. First, Pearson r and Spearman ρ showed that all variables are statistically significant correlations. Second, among the first factors of personal and family characteristics, household income level(B=.113), family composition(B=-.049) and parental education (B=.060) were found on a significant impact on the movement of physical activity time, parental education (B=.027) was found on a significant impact on the subjective evaluation of physical education grades. Third, among the second factors of community-level characteristics, Gini coefficient (B=-.810), wealth concentrating (B=.120) were found on a significant impact on the movement of physical activity time, the Gini coefficient (B=-0.315) was found on a significant impact on the subjective evaluation of physical education grades. Additional factors that determine the coefficient of variation in the level 2 were found to be 0.623 and 0.001 respectively. Therefore, second factors of community-level characteristics are added such as Gini coefficient, wealth concentrating were explained to children and youth exercise time during physical activity 62.3%(p<.01) and subjective evaluation of physical education in grades 0.1%(p<.01). predictive power to
The frailty, characterized by reduced physiological function is closely related to a fall, disability, institutionalization, hospitalization, and mortality in the elderly. A reduced physical fitness is a major phenotype of the frailty. The purpose of this study was to investigate the relationship among pre-frailty, physical activity (PA) and functional fitness in the community dwelling elderly women. The study participants were elderly women (n=338, 70.6±4.2years) aged over 65 who took part in the Korean Healthy Fitness Criteria study for the National Fitness Award Project in 2015. The pre-frailty was defined using the Cardiovascular Health Study frailty criteria. PA was assessed using the International PA Questionnaire (IPAQ). The participants were classified as regular PA participants if they meet the World Health Organization (WHO) PA recommendation for the elderly. Functional fitness was assessed using the composite of the National Fitness Award fitness testing for the elderly. Quality of life was evaluated using EuroQoL visual analogue scale and WHO quality of life assessment. As the results, the pre-frail elderly women were significantly older and obese (body mass index, percent body fat, waist circumference) than the healthy elderly. The pre-frail elderly presented significant decreases in walking, moderate intensity, and total PA compared to the healthy elderly even after adjusted for age and percent body fat. However, no significant difference was found in vigorous-intensity activity between the pre-frail and healthy elderly. Also, the pre-frail elderly women showed the decrease in functional fitness and quality of life compared to the healthy elderly. Regular PA was associated with high levels of muscular endurance and coordination in healthy and pre-frail elderly. In pre-frail elderly, high levels of cardiorespiratory endurance was associated with PA. In conclusion, regular PA is inversely associated with fitness decline in healthy and pre-frail community-dwelling elderly women. Regular PA might attenuate fitness decline in pre-frail elderly women.
PURPOSE This study investigates the effectiveness of biomechanics information on intermediate golfers driver swing learning. It analyzes changes in center of pressure (COP) patterns, GRF Direction Inclination, driver performance, and learners psychological responses to determine the learning effects. METHODS Subjects were 32 right-handed male golfers (handicap 15-23) who had no difficulty in performing the golf driver swing (Full swing). Four groups were selected, BF (Biomechanics Feedback group), BVC (Biomechanics Verbal Cue group), CB (Combination group), and CT (Control group), and assigned randomly. Driver swing learning showed results after 6 weeks,and a transfer test was conducted 1 week after the completion of the learning. RESULTS Analysis of COP patterns and GRF Direction Inclination indicated changes in the BF, BVC, and CB groups. Furthermore, analysis of driver distance (m), club head speed (km/h), and ball spin rate (rpm) revealed that during the 6-week acquisition phase, all three groups (excluding the control group) showed improvements in driver distance, club head speed, and ball spin rate. However, there were no statistically significant differences among the groups. In contrast, the transfer test showed statistically significant differences among the groups, with the CB group exhibiting the highest driver distance. Learners' psychological responses during the learning process were trust, understanding, and satisfaction. The understanding factor was relatively higher in the CB and BVC groups compared to the BF group. CONCLUSIONS In summary, biomechanics information (BI) was effective in improving driver performance, and changesappeared in the COP pattern and GRF Direction Inclination, indicating a change in movement. Therefore, BI can be fully utilized for athletes or high-level advanced players and for motor learning for intermediate-level students.However, BI can only improve learning effects by strengthening learners' “understanding” when visual feedback forms and verbal cues are provided together.
The purpose of this study was to examine the relationship between QTc interval and maximal oxygen consumption(V˙O2max) and body fat distribution in middle-aged men. Abnormal subjects (QTc interval, ≥440ms, n=10) and normal subjects(≤430ms, n=11) using QTc interval based on the Bazzet's equation were involved in the study. After overnight fasting, blood and blood pressure were measured. Abdominal fat area and regional fat compartment were measured by computed tomography(CT) and dual-energy X-ray absorptiometry(DXA), respectively. For V˙O2max, the subjects underwent a maximal graded exercise test on a cycling ergometer. Abnormal group was significantly higher in SBP, basal insulin, HOMA-IR, and leg fat compared with normal. There was a significant relationship(r=.614, p=.03) between QTc interval and V˙O2max in all subjects. Also, partial correlation analysis showed a significant relationship(r=.480, p=.032) between the QTc interval and V˙O2max. Having a QTc interval outside normal range significantly worsened risk parameters for metabolic syndrome, in particular blood pressure and insulin resistance. Moreover, QTc interval was strongly correlated with cardiorespiratory fitness in middle-aged men. This study indicates that further study will be needed to assess the exercise training effects on QTc interval.
Purpose The purpose of this study was to examine the difference and consistency of kinematic variables for each athlete by selecting the official records of the world's elite female triple jumpers to evaluate the performance level. Methods Three athletes who won the prizes at the World Championships Daegu 2011 Women's Triple Jump were selected as the study subjects, and only the successful trials were used for analysis. Pearson's correlation analysis was conducted with the kinematic variables in the hop, step, and jump phase, respectively. Also, kinematic variables with statistically significant correlations between braking time and pushing time and related variables were described separately. The duty factor and support factor for the hop, step, and jump of support phases were calculated. Results The successful trials rate were 66.7% for Olha, 50% for Olga, and 83.3% for Caterine. In the last three stride distances of the approach run, Olha and Caterine had a “medium-long-short” pattern and Olga had a “long-short-medium” pattern. There was no difference in the duty factor value between hop and jump phases in the ‘hop-dominate’ technique type, but there was a difference in the jump phase in the ‘balance’ technique type, and the duty factor value in the step of both technique types was greater than that of hop and jump phases. As for the percentage of the support factor, Olha and Caterine had a characteristic that the percentage of braking time in step and jump phases was opposite. On the other hand, Olga had the same percentage for the hop and step phase, and a smaller percentage for the jump phase. Conclusion To increase the accuracy of the board touch-down, maintain a certain last stride(1SL) depending on the technique type. This consistency of the approach run increases reduces distance loss on the take-off board and increases the successful rate of each trial. The duty factor can judge both the performance level and the technique type of triple jump, and the support factor is a variable that can classify the technique types of hop, step, and jump phases. If both the relative time required for the triple jump and the variability of the support time(braking and pushing) for each phase are constant, the difference in records by trial will be small.
Purpose The purpose of this study was to find out the physical characteristics of Wushu athletes by comparing the differences on the results of physical fitness between the male athletes of the Wushu national team Taolu and the Sanda group. Methods Measurement of basic and professional fitness based on muscle function, targeting 37 men Wushu national team players (24 taolu, 13 Sanda) in the selection and evaluation contests twice in 2018 and 2019. Body composition, isometric muscle strength, flexibility and equilibrium, anaerobic power, and isokinetic muscle strength. The fitness factors were divided into two groups, Taolu and Sanda. Results First, body fat rate of the Sanda athlete group was significantly lower than that of the taolu athlete group (p<.01). Second, in the isometric muscle strength category(back muscle strength, grip strength), the Sanda athlete group had higher muscle strength than Taolu athlete group, but there was a statistically significant difference only in the left grip strength (p<.01). Third, in terms of flexibility and equilibrium, the taolu players were significantly higher in all items(p<.001). Fourth, in the anaerobic power, the taolu athlete group had higher both the peak power and the mean power, and there were a significant differences(peak power: p<.01, mean power: p<.001). Fifth, isokinetic muscle strength was significantly higher in the right knee flexion of the taolu athlete group (p<.01), and lumbar extensor muscle was significantly higher in the Sanda athlete group (p<.05). Sixth, in the isokinetic strength ratio, the knee flexion ratio of the Sanda athlete group were significantly higher on the left and right knee flexion and extensor ratios (p<.05). In addition, in the lumbar flexor and extensor ratios, the group of Sanda athlete group were significantly higher on the lumbar extensor(p<.05). Seventh, there was no significant difference between two groups in isokinetic muscle power. Conclusions The results of this study can be used as basic data to improve the efficiency of technical and physical training through the analysis of the characteristics of Taolu and Sanda. The effectiveness of this training will help to improve the performance.
