PURPOSE This study aimed to verify the criterion validity of the two-minute step test in older Korean adults, develop an equation for predicting VO2max, and verify cross-validation. METHODS A submaximal exercise test and the two-minute walk test were performed on 150 older adults (74 males and 74 females) aged 65 years or older. Correlation analysis was performed to confirm criterion validity. An equation for estimating VO2max was developed through multiple regression analysis, and cross-validation was confirmed by performing a correlation analysis between measured and predicted values of VO2max. RESULTS The correlation coefficient between VO2max and the two-minute step test was 0.457 (p<.001). The adjusted R2 of the developed VO2max prediction equation was 0.430 (p<.001), and the explanatory variables finally selected were sex, age, number of steps in the two-minute step test, and percentage of body fat. The correlation coefficient between the measured VO2max (19.08±4.36) and the predicted VO2max (19.73±3.36) was 0.654 (p<.001). CONCLUSIONS This study confirmed the criterion validity of the two-minute step test in older Korean adults, and the cross-validation of the developed VO2max prediction formula was verified. The explanatory variables of the prediction equation will be easy to apply in the field, and more meaningful results will be derived if the validity of the prediction equation developed for a larger number of participants is verified.
PURPOSE The purpose of this study was to investigate the current injury status and traits, including damage area, cause of damage based on the situation, and type of occurrence by age group for middle and high schools, university, and professional athletes, in record competition sports (swimming, track and field, and weightlifting). METHODS The study included 503 athletes enrolled in the Korean Sport & Olympic Committee in 2020, and an online survey was conducted using the R statistical program. RESULTS Approximately 38.4% athletes suffered injuries with weightlifting (0.81 times at university) and weightlifting (7.02 times at university) during training. The lower extremities were the most affected areas in all age groups (53.8% in middle school, 48.6% in high school, 44.4% in university, and 47.4% in professional). The causes of damage found to occur most frequently were ‘lack of physical strength, overuse or lack of rest, and recurrence’ and external factors, including ‘facility programs and weather problems.’ The results showed that internal factors during training were mostly associated with ‘overuse or lack of rest and excessive attempts at skills’, while external factors were found to occur in ‘weather problems’. According to the classification of each event, the top priority of frequent damage according to the damaged area was skin bleeding of the head in swimming and muscle inflammation in the torso and upper and lower extremities. Track and field resulted in muscle inflammation in the head, torso, and upper and lower extremities. Weightlifting caused damage to the head and torso, resulted in spinal diseases (disc, spinal stenosis, etc.), and muscle inflammation in the upper and lower extremities. CONCLUSIONS This study highlighted changes in the training environment and training environment, including level-specific physical training, reinforcement programs, scientific access to specific skills, sufficient rest and recovery, and continuous improvement of facilities and equipment.