• Journal of the Korean Data and Information Science Society
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• v.23 no.1
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• pp.179-190
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• 2012

The purpose of this study was to verify the contribution of the relationship between coaches-athletes which the athletes have perceived concerning the empowerment and sport motivation on the basis of the relational characteristics between badminton coaches-athletes. The results were as follows. First, the relationship between badminton coaches-athletes had positive effect on the formation of empowerment to badminton athletes. Second, the relationship between badminton coaches-athletes had positive effect on the internal motivation and external motivation among the sport motivation of badminton athletes, while it had no effect on non-motivation. Third, the empowerment of badminton athletes had positive effect on the internal motivation and external motivation, but it had no effect on non-motivation.

• Korean Journal of Exercise Nutrition
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• v.25 no.2
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• pp.20-25
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• 2021

[Purpose] The aim of this review was to discuss the effects of vitamin D on physical performance and musculoskeletal injuries in athletes and provide information on the field applications of vitamin D. [Methods] A systematic review was conducted to identify studies on vitamin D in athletes that assessed serum vitamin D levels, vitamin D and physical performance, vitamin D and musculoskeletal injuries, and practical guidelines for supplementation of vitamin D. [Results] Several studies reported that a high proportion of athletes had vitamin D insufficiency or deficiency. Low serum levels of vitamin D in athletes were more pronounced in winter than in other seasons, and indoor athletes had lower serum vitamin D levels than outdoor athletes. Low vitamin D levels have been demonstrated to have negative effects on muscle strength, power, and endurance; increase stress fractures and other musculoskeletal injuries; and affect acute muscle injuries and inflammation following high-intensity exercises. Therefore, periodic assessment and monitoring of vitamin D levels are necessary in athletes; the recommended serum level of 25(OH)D is > 32 ng/mL and the preferred level is > 40 ng/mL (-1). In those with low levels of vitamin D, exposure to sunlight and an improved diet or supplements may be helpful. Particularly, 2000-6000 IU of supplemental vitamin D3 can be consumed daily. [Conclusion] Vitamin D is a potential nutritional factor that can significantly affect physical performance and musculoskeletal injuries in athletes. The importance and role of vitamin D in athletes should be emphasized, and the current levels of vitamin D should be assessed. Therefore, it is essential to periodically evaluate and monitor serum vitamin D levels in athletes.

• Korean Journal of Community Nutrition
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• v.3 no.1
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• pp.94-106
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• 1998

Nutrient supplements are often used by athletes as ergogenic aids. This study was done to investigate the use of nutrient supplements, nutritional knowledge and nutrient intakes of athletes. Subjects of this survey consisted of 195 national team athletes. The prevalence of nutrient supplement use among all subjects was 30.3%, and the frequency of use, by decreasing order, was weight lifting, taekwondo and badminton athletes. Sport drinks were the type of nutrition supplement used most frequently and vitamin C was the second one. Major reasons for nutrient supplement use were to improve training performance and to recover from fatigue, to supplement fluid and to control weight. The average score of nutritional knowledge was $19.9\pm{2.5}$ for nutrient supplement users, and $19.8\pm{3.6}$ for nutrient supplement nonusers. Intakes of protein, calcium and niacin of the user were higher than those of the nonuser. This information provided by this study can help sport nutritionists identify nutrient supplement most often consumed by national elite athletes and can aid counselors as they guide athletes towards more healthful nutrition practices.

• Journal of the Korean Society of Physical Medicine
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• v.15 no.3
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• pp.1-9
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• 2020

PURPOSE: This study examined the effects of muscle fatigue on proprioception in the type of taekwondo training, causing injury to taekwondo athletes. METHODS: The subjects were divided into Taekwondo Kyorugi athletes (n = 14) and Taekwondo Poomsae athletes (n = 14). After inducing muscle fatigue to the subjects, the joint position sense (JPS) and the force reproduction sense (FRS) were measured before and immediately after the induction of muscle fatigue. RESULTS: Studies have shown no significant impact on the JPS and FRS caused by muscle fatigue induced by Poomsae and Kyorugi (p > .05). The JPS, however, showed a significant difference before and after Kyorugi (p < .05). The FRS showed significant differences before and after Poomsae (p < .05). Through this study, the injuries to taekwondo athletes appear to be influenced by the joint position and force reproduction. Moreover, the injury appears to affect the joint position sense in Kyorugi athletes and the force reproduction sense in Poomsae athletes. CONCLUSION: The results will contribute to injury prevention and athlete protection. In addition, the information can be used as basic data for the development of sports injuries prevention and rehabilitation programs for Taekwondo athletes. Research is needed on the customized management of sports methods and self-care to prevent sports damage, considering the athletic characteristics of the taekwondo athletes in the future.

• Nutrition Research and Practice
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• v.14 no.1
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• pp.45-54
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• 2020

BACKGROUND/OBJECTIVES: This study aimed to examine differences in weight control practices, beliefs, self-efficacy, and eating behaviors of weight class athletes according to weight control level. SUBJECTS/METHODS: Subjects were weight class athletes from colleges in Gyeong-gi Province. Subjects (n = 182) responded to a questionnaire assessing study variables by self-report, and data on 151 athletes were used for statistical analysis. Subjects were categorized into High vs. Normal Weight Loss (HWL, NWL) groups depending on weight control level. Data were analyzed using t-test, ANCOVA, x²-test, and multiple logistic regressions. RESULTS: Seventy-three percent of subjects were in the HWL group. The two groups showed significant differences in weight control practices such as frequency (P < 0.01), duration and magnitude of weight loss, methods, and satisfaction with weight control (P < 0.001). Multiple logistic regression showed that self-efficacy (OR: 0.846, 95% CI: 0.730, 0.980), eating behaviors during training period (OR: 1.285, 95% CI: 1.112, 1.485), and eating behaviors during the weight control period (OR: 0.731, 95% CI: 0.620, 0.863) were associated with weight control level. Compared to NWL athletes, HWL athletes agreed more strongly on the disadvantages of rapid weight loss (P < 0.05 - P < 0.01), perceived less confidence in controlling overeating after matches (P < 0.001), and making weight within their weight class (P < 0.05). HWL athletes showed more inappropriate eating behaviors than NWL athletes, especially during the weight control period (P < 0.05 - P < 0.001). CONCLUSIONS: Self-efficacy was lower and eating behaviors during pre-competition period were more inadequate in HWL athletes. Education programs should include strategies to help athletes apply appropriate methods for weight control, increase self-efficacy, and adopt desirable eating behaviors.

• Nutrition Research and Practice
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• v.15 no.6
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• pp.732-746
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• 2021

BACKGROUND/OBJECTIVES: This study examined the differences in psychosocial factors and eating behaviors by the stages of change (SOC) in nutrition management among elementary and middle school athletes. SUBJECTS/METHODS: Subjects were young athletes recruited from the athletic clubs of 10 organizations. Subjects responded to a survey questionnaire, and data on 167 athletes were analyzed. Subjects were grouped into the pre-action or action stage in nutrition management. The χ² test, t-test, analysis of covariance, and correlation analysis were used in data analysis. RESULTS: Athletes in the action stage (62.3%) compared to the pre-action stage, showed a higher self-efficacy (P < 0.01), and felt more confidence in performing specific eating behaviors (P < 0.05 to P < 0.01). Those in the action stage had more favorable beliefs regarding nutrition (P < 0.001) and agreed less strongly on the specific misconceptions/disadvantages of nutrition (P < 0.01) than those in the pre-action stage. Eating behaviors (P < 0.001) and subscales of the eating behaviors (P < 0.05 to P < 0.01) also differed significantly by the SOC group. Place of eating dinner (P < 0.05) and the person who prepares dinner (P < 0.05) showed significant differences by the SOC group. The relationship of self-efficacy, beliefs regarding nutrition, and eating behaviors to the SOC differed by sports type. Beliefs for football athletes, self-efficacy, and beliefs for baseball athletes were correlated significantly with the SOC, whereas all 3 variables were related to the SOC for handball and other athletes. CONCLUSIONS: This study showed differences in psychosocial factors and eating behaviors between the pre-action and action stages. Nutrition education should include strategies to help young athletes modify their beliefs, mainly misconceptions/disadvantages of nutrition, increase self-efficacy, and adopt specific and desirable eating behaviors. Nutrition education might employ different strategies considering the sports type that student-athletes participate.

• Nutrition Research and Practice
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• v.5 no.4
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• pp.349-356
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• 2011

This study was conducted to investigate relationships and gender differences in dietary supplement (DS) and oriental supplement (OS) prevalence as well as anti-doping awareness during training and the game period. Korea National Sport University athletes (343 male and 136 female) participated in this study and completed DS and OS practice and anti-doping awareness questionnaires. Forty-six percent of athletes used DS during the training period, and there was significantly higher DS use in females (53%) compared to males (43%) (P < 0.05). Twenty-eight percent of athletes used OS, and there was significantly higher OS use in females (35%) than males (26%) (P < 0.05) during the training period. The primary reason of DS use was to supply energy both in males (36%) and females (28%). The main reason for male athletes' OS use was to supply energy (41 %). Meanwhile, the reasons for female athletes' OS use were to supply energy (23%), to maintain health (19%), and to improve recovery ability (20%), which showed a significant gender difference (P < 0.05). Athletes rated their perceived degree of satisfaction, perceived importance, and beliefs in efficacy of DS and OS use all over 50% during the training period, and no gender differences were detected. In a comparison between athletes educated about anti-doping (at least more than one time) and non-received athletes, DS and OS use during the training period was 2.30 (1.47-3.60) and 1.71 (1.03-2.82), respectively. DS and OS use immediately before the game period was 2.38 (1.50-3.80) and 3.99 (1.20-13.28), respectively.Elite athletes' anti-doping education was highly related to increased DS use during the training period and immediately before the game. Although elite athletes use various DS and OS during the training period and before the game period, doping education for elite athletes is related with DS and OS use during the training period and before the game.

• Korean Journal of Psychosomatic Medicine
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• v.3 no.1
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• pp.39-48
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• 1995

This study was designed to investigate the role of weight control in the formation of underlying pathology in eating disorder or eating related problems. The subjects were 304 college athletes(Male : 187. Female: 121) and they were divided into two groups according to need for weight control(Weght control group: 110, Weght non control group: 194). The authors used self report questionnaire which was composed of epidemiologic data, food habit scale, eating attitude test, scale for locus of control for weight, scale for food preference and eating behavior. And we also used Eysenck Personality Questionnaire of Korean standardized edition for assessment of personality characteristics, Beck depression inventory, and the scale of hypochondriasis. The results were as follows: 1) Body mass index and the amount of cigarrette smoking and alcohol drinking showed significant differences by sex but not by need for weight control. 2) Eating habit of female athletes was the worst in all athletes. The score of eating attitude test of female athletes was higher than that of male athletes but there was no significant difference by need for weight control. Food preference and eating related behavior was also different by sex. 3) There were no significant differences in all subscales of Eysenck Personality Questionnaire, Beck depression inventory, and the scale of hypochondriasis between two groups which were divided by need for weight control. Neuroticism score was higher in female atheletes and psychoticism score was the highest in weight control male atheletes. 4) There was no significant difference in number of population with abnormal EAT score(to-tal score$\geq$26) between two groups which were divided by need for weight control. 5) The score of eating attitude test had positive correlation with the score of psychoticism and the tendency of depression in weight control male athletes but not in non-weight control male athletes. In non-weight control male athletes, the score of eating attitude test had positive correlation with the score of lie scale. so its correlation is different from those of weight control male athletes. But in female athletes, the score of eating attitude test had significant positive correlation with the score of psychoticism in both groups. In conclusion, these results suggest that the differences of eating traits in athletes are depend upon the sex difference, not upon the need for weight control. and that the role of weight control in eating disorder or abnormal eating attitude differs according to sex.

• The Korean Journal of Physiology
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• v.18 no.1
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• pp.51-65
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• 1984

In an effort to elucidate the effect of physical training on the electrocardiographic amplitudes, QRS vector, axis and QRS vector amplitude, electrocardiograms were recorded before and 1, 5 and 10 minutes after 3 minute rebounder exercise in 23 healthy male students aged between 18 and 21 years in two groups of athletes and non-athletes. ECG amplitudes were measured from lead I, $V_1$ and $V_5$ and axis and amplitudes of QRS vectors were measured from lead I and III in frontal plane, from lead $V_2$ and lead $V_6$ in horizontal plane. The results obtained are summarized as follows. ECG amplitudes: The R wave amplitude was $23.38{\pm}1.14\;mm$ in athletes which was higher than $17.91{\pm}2.00\;mm$ in non-athletes. After exercise, the difference in two groups remained significant throughout the recovery period. The S wave amplitude was increased significantly, and the T wave amplitude was decreased in both groups after exercise. The P wave amplitude was increased in both groups after exercise, and it was lower in athletes than in non-athletes. The PQ segment amplitude was zero in athletes but negative in non-athletes than in the resting state. The J point amplitude was positive in resting state and was negative after exercise in both groups. J+0.08 sec point amplitude was also lowered after exercise, and it was higher in athletes than in non-athletes. Therefore the whole ST segment was proved to be decreased after exercise. The summated amplitude of R in $V_5$ plus S in $V_1$ was $38.74{\pm}2.71\;mm$ in athletes which was higher than $32.82{\pm}2.90\;mm$ in non-athletes. After exercise, it was also significantly higher in athletes than in non-athletes. Axis of QRS vector: In frontal plane, axis of QRS vector was $62.7{\pm}7.36^{\circ}$ in athletes, it showed no significant difference between the two groups. In horizontal plane, axis of QRS vector was $-23.5{\pm}7.2^{\circ}$ in athletes which was significantly higher than $-38.8{\pm}8.2^{\circ}$ in non-athletes. After exercise, it was significantly higher than the resting state in both groups. Amplitude of QRS vector : In frontal plane, amplitude of QRS vector was $13.86{\pm}1.44\;mm$ in athletes which was significantly higher than $9.62{\pm}0.97\;mm$ in non-athletes. After exercise, it was also significantly higher in athletes than in non-athletes. In horizontal plane, amplitude of QRS vector was $19.82{\pm}2.10\;mm$ in athletes which was significantly higher than $16.90{\pm}1.39\;mm$ in non-athletes. After exercise, it was also significantly higher in athletes than in non-athletes. From the above, these results indicate that R wave amplitude in athletes was significantly higher than in non-athletes before and after exercise, and that the summated amplitude of R in $V_5$ plus S in $V_1$ in athletes was also $38.74{\pm}2.71\;mm$ suggesting a left ventricular hypertrophy We should note that the PQ segment and ST segment amplitude were higher in athletes than in non-athletes, and they were decreased with exercise in both groups. In particular, the fact that amplitudes of QRS vector in frontal plane or in horizontal plane were significantly greater in athletes than in non-athletes may be an index in evaluating athletes.

• Journal of Sport and Applied Science
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• v.6 no.4
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• pp.11-23
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• 2022

New insights into the aetiology of anaemia in athletes have been discovered in recent years. From hemodilution and redistribution, which are thought to commit to so-called "sports anaemia," to iron deficiency triggered by higher requirements, dietary requirements, decreased uptake, enhanced losses, hemolysis, and sequester, to genetic factors of different types of anaemia (some related to sport), anaemia in athletes necessitates a careful and multisystem methodology. Dietary factors that hinder iron absorption and enhance iron bioavailability (e.g., phytate, polyphenols) should be considered. Celiac disease, which is more common in female athletes, may be the consequence of an iron deficiency anaemia that is unidentified. Sweating, hematuria, gastrointestinal bleeding, inflammation, and intravascular and extravascular hemolysis are all ways iron is lost during strength training. In training, evaluating the iron status, particularly in athletes at risk of iron deficiency, may work on improving iron balance and possibly effectiveness. Iron status is influenced by a healthy gut microbiome. To eliminate hemolysis, athletes at risk of iron deficiency should engage in non-weight-bearing, low-intensity sporting activities.