Background At least 60 min of moderate-intensity physical activity per day is recommended for physical and mental health of adolescents. Schools are one of the most suitable places for promoting students’ health as it is a place where vigorous physical activity occurs. However, the physical activity of students is threatened because schools are closed worldwide owing to the coronavirus disease (COVID-19) outbreak in 2019. Therefore, this study aimed to analyze the physical fitness changes in 27,782 Korean adolescents during the pandemic and present alternative education and health policies to the school. Methods We included 29,882 middle school students (age: 13–15 years; males: 14,941, females: 12,841) in Korea from 2019 to 2021 . Participants’ physical fitness at school was measured using the physical activity promotion system (PAPS) manual developed to measure students’ physical fitness. Physical fitness variables included body mass index (BMI), 20 m shuttle run, handgrip strength, sit-and-reach, and 50 m run. Results The COVID-19 pandemic has had a negative impact on the BMI and cardiorespiratory endurance of Korean middle school students. Specifically, male students’ BMI increased, while body composition, cardiorespiratory endurance, and grip strength decreased significantly. Female students showed significant decreases in BMI and sit-and-reach test scores. It is clear that the physical fitness level of adolescents decreased by a greater degree after the COVID-19 pandemic than before, and the decrease in the physical fitness level of male students was noticeable. Therefore, a lesson strategy should be prepared that considers the contents and methods of physical education classes to improve the physical fitness level of male and female adolescents. Conclusions Fitness-based classes suitable for online methods should be urgently added as alternative physical education classes to prepare for the second COVID-19 outbreak. In addition, it is necessary to create an environment in which physical activity is a possibility in physical education classes, in any situation using artificial intelligence and virtual reality.

PURPOSE This study was conducted for the purpose of exploring the direction and quality of Pilates research in the future by comparing and analyzing research trends in the field of Pilates natural science at home and abroad.METHODS In order to analyze domestic and foreign Pilates research trends, we analyzed academic papers of the last 10 years (2013-2022) in the natural science field, and domestic papers were used as the keyword ‘Pilates’ using DP Pia, Kiss, and Riss, which are academic information services. A total of 105 papers were used by searching. For overseas studies, Pub med and Scholar were used, and only SCI and SCIE papers were collected and 129 papers were searched.RESULTS First, according to the comparative analysis of research trends by domestic and foreign fields, physiology (61%), kinematics (24.8%), and rehabilitation (14.2%) were found in the order of domestic, whereas in foreign countries, kinematics (34.9%) and physiology (33.3%) and rehabilitation (31.8%), a study with a relatively even distribution was conducted. Second, in the comparative analysis by study subject, domestic literature was the highest with 68.7% of studies targeting women, and was conducted separately by various age groups. Foreign fields, 40.9% of studies conducted by gender were found, and there were many studies that considered the characteristics of musculoskeletal disorders and metabolic diseases rather than gender. Third, looking at the comparison by research variable, studies have been conducted on various topics in physiology and kinetic dynamics. However, while domestic studies have focused on changes in body composition, foreign studies are actively conducting research on muscle function, musculoskeletal disorders, and rehabilitation.CONCLUSIONS In summary, it is judged that active research in the field of kinematics and rehabilitation should be conducted for more diverse subjects in the field of Pilates.

No abstract

PURPOSE: The purpose of this study is to verify the effect of soft tissue stiffness on joint range of motion and athletic performance in soccer players.METHODS: Fifteen adult male soccer players participated in the study. After the warm-up, calf muscle and Achilles tendon stiffness were measured. Subsequently, range of motion of the ankle joint and 30 m sprint and vertical jump were performed. Exercise performance was assessed as a field test to create an experimental environment similar to that of actual training and competition.RESULTS: Achilles tendon stiffness showed a significant correlation with the 30 m sprint and the vertical jump (<i>p</i><.05). A moderate correlation was observed between the 30 m sprint and the vertical jump(<i>p</i><.01). Soleus muscle stiffness was significantly correlated with the 30 m sprint(<i>p</i><.05). No other correlations were observed.CONCLUSIONS: Therefore, it was confirmed that Achilles tendon stiffness affects exercise performance. In a follow-up study, it was necessary to confirm the effect of the stiffness of various soft tissues on exercise performance.

PURPOSE: This study aimed to investigate the correlation between repeated sprint ability (RSA) and Hoff test performance in high school soccer players.METHODS: Fourteen male high school football players participated in this study. After measuring body composition, the Bangsbo Sprint Test for RSA and Hoff test were performed. The tests were conducted in the field to create an experimental environment similar to that during actual training and competition.RESULTS: A significant correlation was observed between the fatigue index (FI) in the RSA and running distance in the Hoff test (<i>p</i><.05). A high level of correlation between the performance distance and body fat percentage and muscle mass in the Hoff test was observed (<i>p</i><.001). There was no significant relationship between the best and average RSA records using the Hoff test.CONCLUSIONS: It was confirmed that the running distance in the Hoff test developed for event specificity affects the FI in RSA. In subsequent studies, it will be necessary to examine the variables affecting the best and average RSA records.