This study was aimed at investigating the effect of head-tilt angle on autonomic nerve modulation immediately after a single bout of exercise in twenty-three healthy young males(age 21.96 ± .4 yrs). Post-exercise HRV was measured on supine(SUP), -15°head-down tilt(HDT), and +15°head-up tilt(HUT) followed by 20 min aerobic exercise with moderate intensity(40% of VO2max). As results, heart rate recovery during post-exercise on each tilt angle(SUP vs. HDT vs. HUT) had no significant difference(p> .05). Also, there were no significant difference in time and nonlinear domain index of HRV. On spectral analysis; however, frequency domain index(HF, LF/HF ratio, HF/TP ratio, HF nu, LF nu) had significant difference(p< .05) on each tilt angle at recovery. Especially, PNS reactivation index (HF, HF/TP ratio, HF nu) had significant increase on HDT compared to HUT(p<. 05) while SNS activation index (LF/HF ratio, LF nu) had significant decrease on HDT compared to HUT(p<. 05). Furthermore, there were significant interaction between recovery time elapsed and each tilt angle (except for HF/TP ratio). In conclusion, -15°head-down tilt promotes the effective cardiac vagus nerve reactivation immediately after a single bout of aerobic exercise.
PURPOSE This study identifies girls with learned helplessness in middle school physical education coping mechanism and growth process. METHODS Eight female 9th graders who previously experienced learned helplessness in physical education were purposely selected with their physical education teachers’ recommendation. After individual in-depth interviews, data were analyzed using inducted data analysis. RESULTS Findings show that the girls could overcome learned helplessness through their own will and with support of peers and physical education teachers. Moreover, they have undergone various growth processes after coping with learned helplessness. Recently, they have self-confidence in physical education classes and desire to learn physical education. Additionally, results showed that the girls’ learning will in physical education influenced other subject matters, which helped them overcome new challenges in their school and daily lives. CONCLUSIONS Results can be used as practical guidelines to develop educational programs and create policies for girls with learned helplessness.
This study was purposed to explore psychological change and regulation process during badminton competition. The data were conducted using group interviews and participation observations who 18 K college badminton players. The data were analyzed using open, axial, and selective coding based on grounded theory method (Strauss & Corbin, 1998). The results were as follows: Open coding results, 89 concepts, 44 subcategories, and 18 categories emerged as psychological change and regulation process during badminton competitions. Axial coding results, the categories are showed structural relationships such as performance, score, psychological momentum, the importance of competition, court environment, physical condition, competition strategy, psychological preparation, past experience, outcome expectation, psychological disturbance, psychological skills, game situation-changing strategy, support-seeking strategy, significant others' behavior, the opponents' behavior, psychological resilience, and maintenance psychological disturbance. Selective coding results, core category of this study was revealed to maintain psychological homeostasis. Environmental context during badminton competitions causes specific situations and events that evoke psychological disturbance. In turn, a player seeks mental and behavioral strategies to maintain psychological homeostasis. There is psychological homeostasis mechanism during badminton competitions for peak performance. Development of proper interest for psychological homeostasis will be improved through this research approach in sport psychology.
PURPOSE This study conducted a longitudinal analysis of physical activity levels and characteristics of middle-school boys and girls over a three-year period before and after the COVID-19 pandemic. METHODS This study used a sequential mixed-methods research design. In the quantitative study; three-dimensional accelerometers were used to measure weekly physical activity and sedentary time over three years (2019, 2020, and 2021) among 33 middle-school boys and girls, and the data were analyzed using repeated measures analysis of variance. In the qualitative study, data were collected and analyzed through focus group interviews with five participants. RESULTS The quantitative study indicated a significant increase in sedentary behavior and significant decrease in low-intensity activity and MVPA during the first year of the COVID-19 pandemic. In the second year of the pandemic, no significant difference was observed in sedentary behavior, low-intensity activity, and MVPA compared to the data collected in the first year. During the pandemic’s first year, qualitative study identified the following physical activity problems: “lockdowns,” “sedentarization of leisure,” and “reduced structured physical activity.” The following reasons were identified for the lack of improvement in physical activity during the second year: “intensified sedentary lifestyle habits,” “weak social networks,” and “lack of energy to exercise.” CONCLUSIONS The COVID-19 pandemic has led to a significant decrease in physical activity and a significant increase in sedentary behavior among middle-school students in South Korea, and even as the environments for physical activity have recovered, the physical activity problems of the early stages of the pandemic have not improved.
PURPOSE This study aimed to compare body composition, physical fitness, maximum muscle strength, and blood lactate concentration according to the level of aerobic capacity in Keirin cyclists. METHODS Forty-four Keirin cyclists participated in this study and were divided into three groups: the top 20% VO2max group (TG, n=9), the middle 20% VO2max group (MG, n=9), and the low 20% VO2max group (LG, n=9). The study measured body composition, physical fitness, maximum muscle strength, and blood lactate concentration in Keirin cyclists. Differences between groups were determined using one-way ANOVA analysis. RESULTS Body weight, percentage of body fat, and body mass index were significantly higher in the LG than in the TG and MG. The vertical jump and maximum muscle strength were significantly higher in the TG and MG than in the LG. Additionally, blood lactate concentrations immediately after exhaustive exercise and during the 5-minute recovery periods were higher in the LG than in the TG and MG. Moreover, the time to exhaustion, HRmax and maximum power were the highest in the TG. CONCLUSIONS Our findings suggest new information that levels of aerobic capacity in male Keirin cyclists might be a crucial predictor of cycling performance and recovery ability.
PURPOSE The purpose of this study was to develop a non-face-to-face self-regulation training program for middle and high school student-athletes through the conduct of a group online video counseling session, as well as to verify the effectiveness of such a tool. METHODS Based on the models of Zimmerman(2000) and Han Si-wan (2008), the 12-session non-face-to-face self-regulation training program consisting of interactions involving cognitive, emotional, and behavioral factors was developed and used on a 16-member experimental group. Additionally, self-regulation and mental toughness questionnaires were given to each member before and after the program, and the results were compared with the results of a 17-member control group. Since a qualitative evaluation was conducted, recorded training contents were organized into a text file; after which, a step-by-step coding procedure was performed, and then meanings and themes were identified and categorized. RESULTS Quantitative analysis found that the volitional inhibition mode of the control group decreased significantly; this was in comparison to the increase in the self-regulation mode of the experimental group. In addition, among the seven sub-factors of the mental strength test of the experimental group, a significant increase was found in the post-test of self-belief, attention control, emotional regulation, resilience, and optimism factors. As a result of qualitative data analysis, they complained of difficulties in the early stages of participation, but gradually recognized their problems and searched for changes, showed changes in cognition, emotion, and behavior as they approached the end of the study period. CONCLUSIONS It can be said that the non-face-to-face self-regulation training program helped student athletes improve their school life and performance by driving positive cognitive, emotional, and behavioral changes.
PURPOSE The purpose of this review was to summarize the current knowledge on the trends in athletes’ health problems (and their preventive strategies) caused by low energy availability (LEA) and relative energy deficiency in sports (RED-S). METHODS In this narrative review, we summarized previous studies by searching the literature in the PubMed, Google Scholar, and Science Direct databases. RESULTS Energy availability (EA) refers to the amount of energy from caloric intake used for exercise, and a LEA is considered as a surrogate marker of RED-S. In several previous studies, chronic low energy availability in female athletes has been reported to cause health problems such as endocrine dysfunctions, immunosuppression, and psychological disorders, and to also affect the hypothalamic-pituitary-gonadal (HPC) axis and bone health. Moreover, it has been suggested that an increase in injury risk and a decrease in exercise performance may occur. CONCLUSIONS Since it can be difficult to recover from the health deteriorations caused by RED-S, early detection (of related signs and symptoms) and prevention are very important. Therefore, athletes, coaches, and parents need to develop educational programs that ease the recognition of the problems caused by various symptoms related to RED-S and promote educational interventions.
Purpose The purpose of this study was to further understand how out-of-school adolescents’ self-esteem and interpersonal relations have changed in a peer mentoring basketball program and what they have experienced for the program It was action research of qualitative research method. Methods 4 out-of-school adolescents in the adolescents Center of C-si were selected as the participant. The data was collected by in-depth interviews, participant observation, and research journal. The collected data was then analyzed by an inductive categorical system. Results The findings were summarized as follows: the out-of-school adolescents showed somewhat low self-esteem and difficulties of interpersonal relations at an early stage participating in the peer mentoring basketball program. However, their self-esteem and interpersonal relations have been gradually changed during the program. First, they participated in various mentoring activities and self-expression activities. Their self-esteem has been improved as they found their real values, communicated with others, and lived with their confidence. Second, they overcame personal relations with fear and indifference of others, extended personal relations, and sympathized with others to solve the problem that they had as interpersonal relations. Conclusions The out-of-school adolescents has positively changed their self-esteem and interpersonal relations through the peer mentoring basketball program. We expect that out-of-school adolescents could overcome their difficulty and live well their life in the future.
Purpose Incidence and prevalence of Korean teenager cheerleading injuries were surveyed. Methods A total of 769 junior cheerleaders who participated in National Sport Cheerleading Competitions responded to a questionnaire, and 435 reported experiences of injuries. Results Risk factors for injury included older age (p<0.001), increased experience (p<0.001), and higher BMI (p<0.05). The most frequent injury occurred at wrist, ankle, knee, shoulder and waist. And the most responded types of injury were muscular pain and contusion. Cheerleading experience affected on injury prevalence. They were injured when they perform Elevator (<0.5 yrs), Cradle (0.5-1 yrs), Cradle and Basket toss (1-2 yrs), Cradle and Pyramid (2-3 yrs). These techniques involved in bodily movements of going up and cradle. About 56% of injury was treated at home or not treated at all, and 60% of injury was either self-treated or not intervened. And only 32% of cheerleaders practiced on a formal mattress. Conclusion Safety measures for these youth cheerleaders are necessary and guidelines for securing safety and preventing and treating injuries for these population are urgent.
Lactate was considered a dead-end waste product of glycolysis due to lack of oxygen. Accumulating lactate in the muscle and blood was viewed only as a major cause of muscle fatigue and tissue damage. Furthermore, buildup of lactate due to glycogen re-synthesis is thought to cause excess oxygen consumption (oxygen debt) after exercise. However, research has also shown lactate to be an important mediator in numerous metabolic processes and a fuel for aerobic metabolism. Lactate is not metabolic waste, but a major player in cellular and whole body metabolism. Lactate can be used within the cell (intracellular lactate shuttle) or be transported through the cytoplasm or blood to be used by other cells (cell-cell lactate shuttle). Lactate shuttle hypothesis has helped in identifying and understanding the link between the glyoclyic and oxidative pathways, and identified lactate as a major energy source and gluconeogenic precursor. Therefore, the purpose of this review was to better understand the physiological roles of lactate at rest and during exercise, and the concept of lactate shuttle with implications for clinical practice.
