• Korean Journal of Applied Biomechanics
• /
• v.23 no.3
• /
• pp.219-223
• /
• 2013

The purpose of the study was to investigate the effects of gymnasts shoes on risk factors of anterior cruciate ligament injuries during drop-landing followed by vertical jump in female gymnasts. Thirteen female gymnasts were recruited and performed randomly drop-landing followed by vertical jump in height of her knee with and without shoes. Kinematics and ground reaction data were collected to estimate the anterior cruciate ligament injuries risk factors. Data were analyzed with paired samples t-test with Bonferroni correction. Female gymnasts with shoes showed more reduced thigh maximum adduction angle, and knee maximum extension moment than without shoes. Female gymnasts with shoes showed more increased shank maximum abduction angle than without shoes. In conclusion, Female gymnasts with shoes reduced anterior cruciate ligament injuries risk factors.

• Journal of Nutrition and Health
• /
• v.32 no.1
• /
• pp.40-49
• /
• 1999

This study was conducted with 20 female gymnasts and 23 age-matched controls to examine pattern, weight control behavior and nutritional status. Most gymnasts(95.0%) reported that they used weight-control methods, while relatively few age-matched controls employed these methods. These methods included sauna(95.0%), food restriction(90.0%), excess exercise (70.0%), laxative abuse(10%) and use of diet pills(10%). Gymnasts had significantly (p<0.05) lower scores for statements related to 'sneaking food', 'vomiting after overeating', showing more negative eating behavior than age-matched controls. Energy intake of gymnasts was 968.9$\pm$421.4kcal while energy expenditure was 2,091$\pm$361kcal, showing negative evergy balance(-1,1225$\pm$534.6kcal). Female gymnasts consumed less than 70% of the RDA for protein, calcium, iron, vitamin A, thiamin, riboflavin and niacin, which reflects their low energy intake. The average intakes of calcium, iron, vitamin A, thiamin, riboflavin and niacin did not meet the recommended dietary allowances for their age groups. Adolescent athletes who train vigorously and consume a low-energy diet may be exposed to an increase in potential health risks. Therefore, individuals who advise athletic adolescents regarding training and dietary habits need to emphasize the importance of consuming an appropriate energy intake to support performance as well as growth and development. The sports nutritionist is in a position to convey such information to coaches, physicians, parents and to the athletes themselves.

• Journal of Nutrition and Health
• /
• v.32 no.1
• /
• pp.50-63
• /
• 1999

This study was conducted with 20 female gymnasts and 23 age-matched controls to examine the relationship of diet, menstrual function and bone mineral density (BMD). The results obtained are summarized as follows : Energy intake of gymnasts was 968.9$\pm$421.4kcal, and energy expenditure was 2091.4$\pm$361kcal showing negative energy balance(-1,122.5$\pm$534.6kcal). The average intakes of calcium, iron, vitamin A, thiamin, riboflavin and niacin did not meet the Recommended Dietary Allowances for their age groups. Mean age at menarche in gymnasts is 15.8$\pm$1.2 years compared with 11.8$\pm$2.8 years in age-matched controls. The profile of estradiol, progesterone, and luteinizing hormone was lower than age-matched controls but not significant. Athletic amenorrheic gymnasts(n=12) have the menstrual irregularity(n=10) and amenorrhea(n=2). A number of variables as such nutritional deficiency in diet, negative energy blasnce and hypogonadotropic hormonal status were included. The bone mineral density (BMD) of female gymnasts were significantly higher than controls for the lumbar neck(p<0.001), trochanter(p<0.01), and Ward's triangle(p<0.001), but there were no significant differences for the lumbar spine and forearm. The lumbar spine BMD had a positive correlation with age and lean body weight. The femoral neck BMD was significantly associated with age, group and lean body mass. The trochanter BMD had significant relationship with group, body mass index, energy expenditure and follicular stimulating hormone. Ward's triangle BMD were related to body mass index and follicular stimulating hormone. The significant association was deterced between forearm BMD and age and lean body weight. The major finding of this investigation is that the BMD of gymnasts were higher than age-matched controls despite the fact that gymnasts as a group had inadequate dietary calcium and a higher propensity to have an interruption of their menstrual cycle. These data indicate that grymnsts involved in sports producing significant impact loading on the skeleton had greater femoral neck, trochanter and Ward's triangle bone density than age-matched controls.

• 한국체육학회지인문사회과학편
• /
• v.51 no.4
• /
• pp.419-425
• /
• 2012

The purpose of the study was to investigate the effects of knee brace on anterior cruciate ligament injuries risk factors during one-legged landing of female gymnasts. Eleven female gymnasts were recruited and performed randomly one-legged drop landing in height of her's knee with (3times) and without (3times) knee brace. Kinematics and ground reaction data were collected to estimate the anterior cruciate ligament injuries risk factors. Data were analyzed with paired samples t-test. Female gymnasts with knee brace showed more reduced the distance from ankle joint center to knee joint center in sagittal plane and knee maximum joint torque than without knee brace. In conclusion, Female gymnasts with knee brace reduced anterior cruciate ligament stress.

• Korean Journal of Community Nutrition
• /
• v.5 no.1
• /
• pp.50-62
• /
• 2000

This study was conducted with 20 female gymnasts to examine the relationship between eating patterns, diet menstrual function and hematological status. According to the baseline data a nutrition counseling and education program was developed and evaluated improved the nutritional status and health of female gymnasts. Mean body weight at the onset of the study was 42.1$\pm$7.0kg and was reduced to 41.8$\pm$6.1kg after the nutrition counseling and education program. The percent of body fat was significantly reduced from 13.9$\pm$3.7% to 13.1$\pm$3.1%(p<0.01) skinfold thickness of subscapular and thighs was reduced significantly(p<0.01, p<0.05) Mean daily intake levels of energy, protein calcium iron thiamin riboflavin and niacin were significantly elevated after the nutrition counseling and education program but were lower than the Recommenced Dietary Allowances. For the nutrition knowledge and food habits, the posttest mean scores showed a significant increase. The hematological status(hematocrit, serum ferritin) and the early follicle level of estradiol were elevated to a mild degree although it was not significant,. The follicular stimulating hormone level was elevated significantly(p<0.01) Gymnastica has been one of the sports implicated by the medical profession as having probable detrimental effects. The implications of such training to childs growth and maturation have yet to be determined . Most female athletes, however, experience poor nutritional status and delayed puberty The priorities were to prepared a more effective nutrition program and education material status and delayed puberty. The priorities were prepared a more effective nutrition program and educational material for athletes coaches and adminstrators to prepare guidelines for the team physicians and coaches to follow for the physical and physiological examinations of female athletes.

• Nutritional Sciences
• /
• v.8 no.2
• /
• pp.118-124
• /
• 2005

To examine the eating attitudes, weight concerns, dietary intake, and menstrual function of Korean female elite athletes, 109 subjects in seven sports disciplines (rhythmic gymnastics, synchronized swimming, badminton, volleyball, Taekwondo, field hockey, and soccer) responded to a questionnaire consisted of three parts; eating attitudes and behavior(Eating Attitude Test-26; EAT26), body weight perception (Body Dissatisfaction Index: BDI) and weight control behavior, and menstrual history and status. They also recorded three-day dietary intake. Body weight (43.6$\pm$4.3 kg) and body mass index (16.7$\pm$1.4 kg/$m^2$) in rhythmic gymnasts were lower than those in other athletes (P<0.05). EAT26 scores were not different among sport events (12.3$\pm$6.5 total), however, eating disturbances (EAT26 score$\geq$20) were highly prevalent in aesthetic athletes ($30\%$) than in others ($5\%$). More than half of the athletes perceived themselves overweight and four fifth of the athletes desired to reduce weight about 4.4 kg. The gymnasts consumed the lowest caloric intake (1028:t371) while the volleyball players did the highest (2995$\pm$342 kcal/d) (P<0.05). The BDI score was not different among sport events. Three fourth of the athletes experienced weight control, and the most frequently used weight reduction method was exercise followed by using robber suits, diet, and sauna. About $40\%$ of the subjects reported irregular menstrual cycles, but menstrual dysfunction ($\leq$6 menses/yr) was only $5\%$. Generally, the Korean female elite athletes desired to reduce weight from their current body weight. No differences in eating attitude and body dissatisfaction were noticed among athletic disciplines. However, eating disturbances were highly prevalent in aesthetic athletes who also reported much less energy intake than the recommend daily energy intake. It appeared that weight reduction methods were not properly practiced in these population. Menstrual dysfunction was minimally reported.

• Journal of Korean Home Economics Education Association
• /
• v.12 no.1
• /
• pp.59-73
• /
• 2000

The purpose of this study was to investigate the percent of body fat. fatness indices. and relationship between the percent body fat and dietary factors among the female middle school athletes. Hights, weights, an percent body fats of 17 soccer player. 10swimmer, and 5 rhythmic gymnast were measured. Dietary data were collected by questionnaires. The results of this study are summarized as follows. 1. Average body fat measured by infrared interactance method was 23.8$\pm$4.9% and BMI body fat was 20.3$\pm$2.6% Fatness indices such as BMI was 18.8$\pm$2.1 Rohrer index 119.4$\pm$11.8 percentage of ideal weight 90.4$\pm$9.2 and RBW 29.7$\pm$4.1. 2. Soccer player, swimmer, and rhythmic gymnast showed significant differences in percent body fat and fatness indices. ryhthmic gymnasts were smaller and lighter. 3. Most athletes were interested in diet and nutrition. and wanted to learn more about nutrition. Middle school female athletes ranked parents first or second for nutrition information. followed by managers$.$coaches$.$trainers. 4. Nutrition knowledge test score was 4.7 point out of possible 10, which is rather low, and showed significant difference in 3 kinds of players. 5. The quantities of food eaten in breakfast. lunch dinner and snack were significantly different among soccer player. swimmer. and rhythmic gymnast. In preference score of food groups, only beverage score was significantly different and of cooking methods. roasting and steaming were significantly different among the soccer player. swimmer. and rhythmic gymnast. 6. When subjects were divided into 3 groups on the basis of % infrared body fat, subjects with the highest body fat showed the tendency to eat more than others(non-sig). In the preference score of food groups. only fish showed significant difference among the groups. There were no significant differences between body fat and preference of various cooking method.

• Korean Journal of Applied Biomechanics
• /
• v.32 no.1
• /
• pp.24-30
• /
• 2022

Objective: The purpose of this study was to determine the factors of successful and unsuccessful movements through the analysis of kinematics and muscle activity of the Free Aerial Cartwheel on the balance beam. Method: Subjects (Age: 22.8 ± 2.4 yrs., Height: 158.7 ± 5.0 cm, Body mass: 54.1 ± 6.4 kg, Career: 13 ± 2.4 yrs.) who were currently active as female gymnasts participated in the study. They had no history of surgical treatment within 3 months. Subject criteria included more than 10 years of professional experience in college and professional level of gymnastics and the ability to conduct the Free Aerial Cartwheel on the Balance Beam. Each subject performed 10 times of Free Aerial Cartwheel on the balance beam. One successful trial and one unsuccessful trial (failure) among 10 trials were selected for the comparison. Results: It was found that longer time required in case of unsuccessful trial when performing the Free Aerial Cartwheel on the balance beam compared with successful trial. It is expected to be the result of movement in the last landing section (i.e. phase 5). In addition, it was found that the center of gravity of the body descends at a high speed to perform the jump (i.e. phase 2) in order to obtain a sufficient jumping height when the movement is successful while the knee joint is rapidly extended to perform a jump when movement fails. In the single landing section after the jump (i.e. phase 4), if the ankle joint rapidly dorsiflexed after take-off and the hip joint rapidly flexed, so landing was not successful. Conversely, in a successful landing movement, muscle activity of the biceps femoris was greatly activated resulting no shaking in the last landing section (i.e. phase 5). Conclusion: In order to succeed in this movement, it is necessary to perform a strong jump after rapidly descending the center of gravity of the body using the force of the biceps femoris muscle. Further improvement of the skills on the balance beam requires the analysis of the game-like situation with continuous research on kinematic and kinematic analysis of various techniques, jumps, turns, etc.

• Korean Journal of Applied Biomechanics
• /
• v.19 no.1
• /
• pp.49-58
• /
• 2009

This study aims to analyze the association between the center of mass(C.O.G) and ocular movement(E.O.G) according to the success and failure in the left turn motion on the balance beam, targeting three female gymnasts. When successful, the left-right C.O.G was moved to the left, which was a rotational direction until such time as the body rotated $180^{\circ}$, whereas there appeared to be a greater movement during failure; thus, it was shown to affect the maintenance of dynamic postural control. In case of the subsequent left-right turning motion of E.O.G, this matches the previous theory that the eyeball moves against the direction of rotation of the body. However, there was a difference at the time of movement, and a clear difference emerged in the success and failure in this study. Also, in the E.O.G in the up-down direction, a movement during failure showed a pattern of down direction in most cases; thus, it is deemed to affect the failure. Therefore, the kinetic postural control and E.O.G are supposed to affect the success and failure in a landing, which is the most importantly evaluated movement on the balance beam, in mutual association.