Annals of Applied Sport Science

Background. Effective kick-topspin serving in tennis requires power to transfer mechanical energy through a kinematic chain from different parts of the body that is directly related to the kinetics of the joints. Energy flow analysis is a powerful tool for observing the mechanical energy transfer through the body parts.
Objectives. This research aimed to study the correlation and predictive ability of the independent variables affecting the energy flow in a topspin kick serve.
Methods. Ten male tennis players aged 19 - 25 were recruited by purposive sampling and consisted of elite and amateur tennis players. The movement patterns of the kinetic chain mechanism and the energy flow in kick topspin tennis serve were recorded with six motion cameras with a force platform and motion analysis program to analyze their 3D motion. The relationship and comparison with the independent variables affecting the dependent variable at seven joints were investigated using Multiple Analysis of Variance (MANOVA) and Stepwise multiple regression analysis for the predicted equation (p<0.05).
Results. The results showed no significant differences in the seven body joints in both groups. The correlation and predictability revealed that the variables were used to transfer and release mechanical energy differently in three distinct phases.
Conclusion. The effective kinetic chain and energy flow lead the mechanical energy to the segment of the body to achieve proper position and energy transfer; smooth coordination leads to greater speed in the acceleration phase to the follow-through phase in the tennis serve.

Background. The spread of COVID-19 has several impacts on health behavior.
Objectives. This study was to study changes in health behaviors and factors influencing the health behaviors of office workers (OW) living in Bangkok during the Covid-19 pandemic.
Methods. The online survey was designed to collect data on physical activity (PA), sedentary behavior (SB), stress, healthy food consumption, and sleep quality from 494 OW. Multinomial logistic regression was used to determine the factors influencing health behaviors due to the pandemic.
Results. During the pandemic, OW reported having good health, healthy food consumption, good sleep quality, and moderate PA (p < 0.05); but their stress and SB were increased (p < 0.05). Undergraduate OW reported being 4 times healthier than those with postgraduate education (OR = 4.30). Those with bachelor's degrees reported 3 times less stress than OW with postgraduate degrees (OR = 3.54). The PA of OW who earn 20,000-30,000 Baht/month was 3 times lower compared to higher earners (OR = 3.11). Younger and female OW had 2 times increase in SB (OR = 2.01 and 2.30, respectively). If returned to normal, OW wants to work as a hybrid, be more physically active, eat a nutritious diet, put greater emphasis on sleep and reduce SB.
Conclusions. Changes in health behaviors as a result of an epidemic depend on several factors, including age, education, and accommodation. After the pandemic, Bangkok OW increased its desire to take care of its health.

Background. Globally, physical activity among children and adolescents is declining, with only 27% of Thai youth meeting the recommended 60 minutes daily. This trend raises public health concerns and emphasizes the role of school-based interventions. While rural children often have more active lifestyles, urban students face environmental and academic constraints. Comparative studies in the Thai context remain scarce.
Objectives. This study aimed to compare physical competence, comprising physical fitness and motor performance, among students in rural and urban Thai schools to assess the impact of contextual differences.
Methods. A total of 223 students aged 10–12 years were assessed using CAPL-2 across four schools: Tak rural school: n=66, Suphanburi: n=66, Chulalongkorn University Demonstration School: n=38, Srinakharinwirot University Demonstration School: n=53. The PACER, plank test, and CAMSA were used to evaluate aerobic fitness, muscular endurance, and motor performance. Group differences were examined using one-way ANOVA with post-hoc tests and partial η².
Results. Students from the Tak rural school had significantly higher overall physical competence and motor performance, while those from Chulalongkorn University Demonstration School performed best in muscular endurance. Suphanburi students consistently showed the lowest scores. All differences were statistically significant (p<0.001).
Conclusion. School context significantly influences children's physical competence. Rural environments support more natural movement, while urban schools may benefit from targeted endurance training.