Development of Reference Point of Doping Attitude and Dispositions for Anti-Doping Education Notification of Athletes: Application of Reference Group Model.

Background: We developed a reference point by applying a doping attitude and propensity tool to prevent doping in sports athletes. Methods: Performance Enhancement Attitude Scale (PEAS) was investigated on 768 registered athletes with the Korea Sports Association. Independent sample t-test and ANOVA were applied to confirm the doping attitude and propensity according to anti-doping education and event type. To establish the criteria for PEAS, the intersection was confirmed through the group comparison method, and EasyOZ by Excel was applied at this time. In addition, accuracy, sensitivity, and specificity were calculated to confirm the validity of the reference point. Results: First, in the case of anti-doping education, it was confirmed that more than 90% of the anti-doping education was completed in all sports. Second, there was no statistically significant difference in PEAS according to the type of sport, and there was only a difference in the PEAS according to whether or not anti-doping education was provided and whether or not there was anti-doping education. Third, the point of contact established in the group comparison method was 29.5 points, and as a result of validating the validity based on this, 30 points were found to be the most suitable index. Conclusion: This study could be used as important information in that it suggests a different method for evaluating PEAS and establishes a reference point that can be used more effectively in the actual field.

Taekwondo win-loss determining factors using data mining-based decision tree analysis: focusing on game analysis for evidence-based coaching.

BACKGROUND: Purpose In this study, the purpose of this study is to identify the determinants of winning and losing in taekwondo by applying decision tree analysis, one of the data mining techniques, based on the 2022 World taekwondo championships women's competition. METHODS: 272 women's games in the taekwondo championships in Guadalajara held by the WT in 2022 were used. For data processing, an independent sample t-test was performed for differences in game content variables according to the win/lose group, and a decision tree analysis was performed to confirm game content variables affecting the win/lose group. To check the predictive power of the model, classification accuracy, standard error, and misclassification estimates were calculated. All statistical significance levels were set at 0.05. RESULTS: First, it was found that there was no statistically significant difference only in body attack (attempt) and number of kicking variables according to the winning and losing groups(p > .05), and there were differences in all other game content variables(p < .05). Second, as a result of conducting a decision tree analysis to confirm the determinants of winning and losing in taekwondo sparring, winning situation, tie situation, and number of kicks were identified as important variables. CONCLUSION: The World taekwondo championships are analyzed in the currently changed taekwondo competition rules to identify important factors, and at the same time, based on this, data-based coaching is expected to improve performance.

Correlation between Ethical Sensitivity as Well as Doping Attitude and Dispositions in Taekwondo Kyorugi Athletes: Athlete Career and National Team Moderation Effect.

Background: We aimed to examine the effect of ethical sensitivity on doping attitude and dispositions for Taekwondo athletes, as well as whether there was a difference depending on the athlete's career and national team status. Methods: Overall, 331 Korean adult Taekwondo athletes were enrolled. Data were collected using sports ethical sensitivity and Performance Enhancement Attitude Scale (PEAS) tools as the research tools. For data processing, frequency analysis was performed to confirm demographic characteristics, and the fitness index was calculated by applying the Rasch model to confirm the validity and reliability of ethical sensitivity and PEAS. An independent sample t-test was performed to confirm the difference between ethical sensitivity and doping attitude and dispositions according to demographic characteristics. Pairwise parameter comparison values were used using multi-group analysis of path analysis to confirm the effect of ethical sensitivity on PEAS and the moderating effect was calculated. Results: First, according to the demographic characteristics of Taekwondo athletes, there were statistically significant differences in ethical sensitivity and PEAS only by gender. Second, as ethical sensitivity factors, both intentional behavior factors and intentional collusion factors had statistically significant effect on PEAS. Third, in the effect of ethical sensitivity on doping attitude and dispositions, there was no moderating effect of athlete experience and national representative status. Conclusion: Ethical sensitivity has a positive linear correlation with PEAS. In other words, enhancing the ethical sensitivity of sports players will enhance athletes' ethical consciousness and prevent unethical behavior, and furthermore, doping.

The effects of fluid absorption and plasma volume changes in athletes following consumption of various beverages.

BACKGROUND: To verify the hydration effects of oral rehydration solution (ORS) on athletes by comparing the degrees of fluid absorption and plasma volume changes following beverage consumption, including ORS. METHODS: Thirty-one participants visited the testing laboratory 4 times at 1-week intervals to consume 1 L of beverage (e.g., water, ORS, and two sports drinks [SpD]) for 30 min on each visit. The urine output was measured 4 times at 1 h, 2 h, 3 h, and 4 h after beverage consumption. A blood sample was collected 3 times at 1 h, 2 h, and 3 h after beverage consumption. Body weight was measured once in 4 h after beverage consumption. RESULTS: Body weight change was smaller for ORS than for water, SpD1, and SpD2 (p < 0.05). Cumulative urine output in 4 h was lower for ORS, SpD1, and SpD2 than for water (p < 0.05), and it was lower for ORS than for SpD2 (p < 0.05). BHI in 4 h was higher for ORS, SpD1, and SpD2 than for water (p < 0.05), and it was higher for ORS than for SpD2 (p < 0.05). There was no significant difference in PVC for different beverages at all test times, i.e.., 1 h, 2 h, and 3 h. CONCLUSIONS: We evaluated the hydration effects of the consumption of beverages, such as water, SpD, and ORS in athletes. ORS and SpD were more effective than water. A comparison between ORS and SpD showed that the result could vary depending on the type of SpD.

Relation of Flatfoot Severity with Flexibility and Isometric Strength of the Foot and Trunk Extensors in Children.

BACKGROUND: Flatfoot is a deformity in which the foot is flattened due to a decrease in or loss of the medial longitudinal arch. STATEMENT OF THE PROBLEM: Few studies have investigated the relationship between the severity of flat feet, trunk strength, and joint flexibility. PURPOSE: The aim of this study is to investigate the relationship between the severity of flatfoot and joint flexibility and foot and trunk strength in children with flexible flatfoot. METHODS: This study included 16 children (boys, 12; girls, 4; age, 4~8 years) with flexible flatfeet. We examined the resting calcaneal stance position angle (RCSPA) and foot posture index (FPI) scores for clinical severity and radiographic parameters, such as calcaneal pitch angle, talometatarsal angle (TMA), and talocalcaneal angle (TCA). Muscle thicknesses of the tibialis posterior (TP), peroneus longus (PL), and L1 multifidus were measured by sonography. Isometric contraction of ankle inversion, eversion in a seating position, and lumbar extension at a prone position were induced using a handheld dynamometer to measure the maximum muscle strength for each muscle. Beighton's scoring system was used to assess joint flexibility by evaluating the hyperextension of the joint for each category when performing stretching motion. Spearman's rank correlation coefficient for nonparametric data was used. RESULTS: The FPI showed a moderately negative correlation with the muscle thickness of TP (r = -0.558, p = 0.009) and L1 multifidus (r = -0.527, p = 0.012), and the strength of the ankle inverter (r = -0.580 p = 0.005) and lumbar extensor (r = -0.436 p = 0.043). RCSPA showed a moderately positive correlation with TCA (r = 0.510, p = 0.006). Beighton's score showed no significant correlation with all parameters. CONCLUSION: In children with flatfoot, FPI reflected the clinical severity; thus, the more severe the symptoms, the weaker the ankle inverter and lumbar extensor.

Adequacy of setting standards for kick impact in the Taekwondo electronic scoring system: comparison of a reference group model based on empirical data.

BACKGROUND: In Taekwondo competitions, the rule is that points are scored when the impact of the kick reaches a predetermined threshold of strength. This study aimed to explore the adequacy of the protector and scoring system (PSS) designed to determine taekwondo body scoring based on a reference group model (RGM). Specifically, the kicking impact of the PSS was calculated using data from 188 matches fought during of 2018 Jakarta Asian Games. The RGM was designed based on empirical data by classifying the victory and defeat groups by gender and weight class, and the scoring method was set according to these criteria. RESULT: The result of this study are as follows. First, there was no difference in the average impact of kicks of taekwondo players by weight class. Second, result of setting up the kick scoring impact standards of taekwondo PSS by classifying the winning and non-winning groups, the kick scoring impact set by the WT was found to be high in all weight classes except 58 kg. Lastly, result of comparing the settings of impact to score according to weight classes, the kick scoring impact standard set by the WT was higher in heavyweight (men's: under 80 kg, + 80 kg, women's: under 67 kg, over 67 kg) than in the lightweight (men's: under 58 kg, under 63 kg, under 68 kg, women's: under 49 kg, under 53 kg, under 57 kg). CONCLUSION: The kick scoring impact set by the WT was found to be high in all weight classes except for the under 58 kg class defining kick scoring impact based on the standards of WT-certified PSS by classifying the matches into winning and non-winning groups. Finally, as a result of comparing the scoring impact settings according to weight class, the kick scoring impact standard set by the WT was higher for the heavier weight classes than for the lighter weight classes.

Differences in body composition of upper and lower limbs in elite taekwondo athletes / Diferencias en la composición corporal de los miembros superiores e Inferiores en atletas de taekwondo de élite

In this study, we analyzed the differences in body composition among athletes during different stages of their career Forty taekwondo athletes and 10 non-athletes (20 males and 30 females) with a mean age of 18.2 years (range, 15-23 years), a mean height of 173.4 cm, and a mean body weight of 64.8 kg were studied using dual energy X-ray absorptiometry and Biodex balance system. The bone mineral density of upper and lower limbs was higher among university athletes of both sexes than in high school athletes. The lean body mass of male athletes in the university was higher than in high school male athletes. By contrast, in case of females, the opposite results were obtained for the upper and lower limbs. Elucidation of the body composition according to career and sex of taekwondo athlete is worthwhile.

En este estudio, analizamos las diferencias de la composición corporal entre los atletas durante las diferentes etapas de su carrera. Se estudiaron cuarenta atletas de taekwondo y 10 no atletas (20 hombres y 30 mujeres) edad media de 18,2 años (rango, 15-23 años), una altura media de 173,4 cm y un peso corporal medio de 64,8 kg. Se utilizaron la absorciometría de rayos X de energía dual y el sistema de equilibrio Biodex. La densidad mineral ósea de las miembros superiores e inferiores fue mayor entre los atletas universitarios de ambos sexos, que en los atletas de educación secundaria. La masa corporal magra de los atletas varones en la universidad fue mayor que en los varones de la educación secundaria. Por el contrario, en el caso de las mujeres, se obtuvieron los resultados opuestos para las miembros superiores e inferiores. En conclusión se debe considerar un análisis de la composición corporal según la carrera y el sexo del atleta de taekwondo.

Reliability and quantification of gastrocnemius elasticity at relaxing and at submaximal contracted condition.

AIMS: To investigate the feasibility of quantitative analysis of muscle stiffness by Acoustic Radiation Force Impulse (ARFI) imaging, to obtain the reference values at relaxing and contraction position of gastrocnemius medialis (GCM) and to evaluate the inter-observer and intra-observer reliabilities of shear wave velocities measurements in healthy skeletal muscles. MATERIAL AND METHODS: The stiffness of the left GCM muscle of 15 healthy volunteers was measured by ARFI elastography in transverse scan while the ankle was in the relaxed position and in 30 degrees of plantar flexion with the submaximal isometric contraction. All subjects were examined by two experienced physiatrists with four years of experience. Reliability of ARFI measurements was assessed by means of the intraclass correlation coefficient (ICC). Interobserver and intra-observer reliabilities were statistically analyzed. RESULTS: The mean shear wave velocity (SWV) of GCM at plantar flexion position with submaximal isometric contraction was significantly higher than that at relaxed position (first physiatrists: plantar flexion with submaximal isometric contraction 2.41±1.09 m/s, relaxed 0.84±0.28 m/s, second physiatrist: plantar flexion with submaximal isometric contraction 2.49±0.94m/s, relaxed 0.83±0.21), p<0.05. The inter-observer reliability was excellent for ankle-plantar flexion with submaximal isometric contraction (ICC=0.968), and good for relaxed position (ICC=0.891) respectively. The intra-observer reliability for ankle-plantar flexion with submaximal isometric contraction were excellent (ICC: first physiatrist 0.98 and second physiatrist 0.96) and that for relaxed position (ICC: first physiatrist 0.98 and second physiatrist 0.90) were also excellent. There was no significant correlation between SWV and body mass index. CONCLUSIONS: ARFI elastography is a reliable imaging modality for quantifying the stiffness of contracting muscles. Additionally, the characterization of pathological soft tissues by ARFI elastography would be a promising clinical practice for patients with musculoskeletal issues.

Clinical Characteristics of Sleep-Disordered Breathing in Subacute Phase of Stroke.

OBJECTIVE: To assess the frequency and severity of sleep-disordered breathing (SDB) in subacute stroke patients in Korea. METHODS: We consecutively enrolled subacute stroke patients who were transferred to the Department of Rehabilitation Medicine from February 2016 to August 2016. The inclusion criteria were as follows: diagnosis of the first onset of cerebral infarction or hemorrhage in the brain by computed tomography or magnetic resonance imaging; patients between 18 and 80 years old; and patients admitted within 7 days to 6 months after stroke onset. We evaluated baseline clinical data on patients' admission to the Department of Rehabilitation Medicine. We assessed demographic data, stroke severity, neurologic impairment, cognition and quality of life. We used the Epworth Sleepiness Scale to assess quality of sleep. We used a portable polysomnography to detect SDB. RESULTS: Of the 194 stroke patients, 76 patients enrolled in this study. We evaluated and included 46 patients in the outcome analysis. The mean apnea-hypopnea index (AHI) was 24.2±17.0 and 31 patients (67.4%) exhibited an AHI ≥15. Those in the SDB group showed a higher National Institutes of Health Stroke Scale, lower Functional Ambulation Category, lower Korean version of Modified Barthel Index, and lower EuroQol five dimensions questionnaire (EQ-5D) at admission. Prevalence and clinical characteristics of SDB did not show significant differences among stroke types or locations. CONCLUSION: SDB is common in subacute stroke patients. SDB must be evaluated after a stroke, particularly in patients presenting severe neurologic impairment.