Hyun-Bae Kim

Treadmill exercise ameliorates symptoms of attention deficit/hyperactivity disorder through reducing Purkinje cell loss and astrocytic reaction in spontaneous hypertensive rats

Attention deficit/hyperactivity disorder (ADHD) is a neurobehavioral disorder of cognition. We investigated the effects of treadmill exercise on Purkinje cell and astrocytic reaction in the cerebellum of the ADHD rat. Adult male spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKYR) weighing 210± 10 g were used. The animals were randomly divided into four groups (n= 15): control group, ADHD group, ADHD and methylphenidate (MPH)-treated group, ADHD and treadmill exercise group. The rats in the MPH-treated group as a positive control received 1 mg/kg MPH orally once a day for 28 consecutive days. The rats in the treadmill exercise group were made to run on a treadmill for 30 min once a day for 28 days. Motor coordination and balance were determined by vertical pole test. Immunohistochemistry for the expression of calbindinD-28 and glial fibrillary acidic protein (GFAP) in the cerebellar vermis and Western blot for GFAP, Bax, and Bcl-2 were conducted. In the present results, ADHD significantly decreased balance and the number of calbindin-positive cells, while GFAP expression and Bax/Bcl-2 ratio in the cerebellum were significantly increased in the ADHD group compared to the control group (P< 0.05, respectively). In contrast, treadmill exercise and MPH alleviated the ADHD-induced the decrease of balance and the number of calbindine-positive cells, and the increase of GFAP expression and Bax/Bcl-2 ratio in the cerebellum (P< 0.05, respectively). Therefore, the present results suggested that treadmill exercise might exert ameliorating effect on ADHD through reduction of Purkinje cell loss and astrocytic reaction in the cerebellum.

Effect of 8 weeks of pre-season training on body composition, physical fitness, anaerobic capacity, and isokinetic muscle strength in male and female collegiate taekwondo athletes.

The purpose of the study was to determine the effect of 8 weeks pre-season training on body composition, physical fitness, anaerobic capacity, and isokinetic strength in collegiate taekwondo athletes. Thirty-four collegiate athletes (male: 22, female: 12) participated. Body composition, bone mineral density, physical fitness, anaerobic capacity, and isokinetic muscle strength were tested. After statistical analysis was performed the results indicated that there were significant decreases in body weight, percent body fat, and fat tissue after 8 weeks of pre-season training. Bone mineral density increased significantly only in males. There were significant improvements in the 50 m shuttle run and 20 m multistage endurance run in both males and females. The sit & reach test and standing long jump were not significantly changed after 8 weeks. Relative peak power and anaerobic capacity were significantly improved in males. Significant increases in angular velocity were observed for knee extension at both % BW 60°/sec and 180°/sec in both males and females. A significant increase in angular velocity was seen for right knee flexion at % BW 60°/sec for males, but it decreased at % BW 180°/sec for both males and females. In conclusion, this study suggests that 8 weeks of pre-season training has a positive effect on body composition, physical fitness, anaerobic capacity, isokinetic muscular strength, and endurance. Nevertheless, an exercise approach with the goal of increasing lean tissue, and improving power in knee flexors and flexibility of athletes, should be included in the training program.

Influence of mild traumatic brain injury during pediatric stage on short-term memory and hippocampal apoptosis in adult rats

Traumatic brain injury (TBI) is a leading cause of neurological deficit in the brain, which induces short- and long-term brain damage, cognitive impairment with/without structural alteration, motor deficits, emotional problems, and death both in children and adults. In the present study, we evaluated whether mild TBI in childhood causes persisting memory impairment until adulthood. Moreover, we investigated the influence of mild TBI on memory impairment in relation with hippocampal apoptosis. For this, step-down avoidance task, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay, and immunohistochemistry for caspase-3 were performed. Male Sprague-Dawley rats were used in the experiments. The animals were randomly divided into two groups: sham-operation group and TBI-induction group. The mild TBI model was created with an electromagnetic contusion device activated at a velocity of 3.0 m/sec. The results showed that mild TBI during the pediatric stage significantly decreased memory retention. The numbers of TUNEL-positive and caspase-3-positive cells were increased in the TBI-induction group compared to those in the sham-operation group. Defective memory retention and apoptosis sustained up to the adult stage. The present results shows that mild TBI induces long-lasting cognitive impairment from pediatric to adult stages in rats through the high level of apoptosis. The finding of this study suggests that children with mild TBI may need intensive treatments for the reduction of long-lasting cognitive impairment by secondary neuronal damage.

A follow-up study on the physique, body composition, physical fitness, and isokinetic strength of female collegiate Taekwondo athletes

The purpose of the study was to analyze changes in physique, body composition, physical fitness, and isokinetic strength in female collegiate taekwondo athletes. The study included 14 subjects, of whom 8 were followed up throughout the study. Anthropometric characteristics included body weight, height, sitting height, circumferences, and bone width. Physical fitness parameters included flexibility, agility, muscle strength, muscular endurance, power, speed, and cardiorespiratory endurance. Peak torque, mean power, and H/Q ratio were analyzed by using Cybex 770. All data were analyzed by using the SAS statistical program. Paired t test was performed, with 0.05 as the significance level. The results indicated significant changes in body weight, and upper arm and flexed upper arm circumferences during the experimental period. Test scores for plate tapping, and sit and reach significantly increased, but that for power decreased. In addition, the peak power of right flexion at 180°/sec was significantly increased, as well as the mean power of right and left flexion, and the H/Q ratio at 180°/sec.

An Investigation into the History of the Taekwondo Uniform since the Korean Peninsula’s Liberation from Japan

Abstract This paper investigates the complex history of the taekwondo sport uniform. Although the uniform is an outward symbol of South Korea’s most popular martial art and national sport, few researchers have elucidated the uniform’s history. From studies into martial art uniforms, and the taekwondo uniform in particular, it is discovered that the tradition of wearing white trousers and jacket began with judo in the nineteenth century. This tradition was carried over to karate and other Japanese martial arts in the early twentieth century. After the liberation of the Korean peninsula from Japan, the taekwondo uniform began to evolve from its Japanese progenitors. The first important changes to the taekwondo uniform were implemented by Hwang Gi, who altered it to meet a traditional Korean clothing style. The 1970s saw the second important transformation to the uniform, whereby it became exclusively regarded as sports attire. However, since the 1970s, the taekwondo uniform did not account for traditional Korean clothing styles, and it faced several criticisms. Recent changes to the World Taekwondo Federation’s poomsae uniform have addressed these problems. The distinctiveness of the new uniform will further distinguish it from its Japanese counterparts, and help to promote the true identity of taekwondo, as well as Korean culture, worldwide.

Comparison of nutritional intake, body composition, bone mineral density, and isokinetic strength in collegiate female dancers

This study compared nutritional intake, body composition, bone mineral density, and isokinetic strength by dance type in collegiate female dancers. The study subjects included Korean dancers (n=12), ballet dancers (n=13), contemporary dancers (n=8), and controls (n=12). Nutritional intake was estimated using the Computer Aided Nutritional Analysis Program. Body composition and bone mineral density were measured using dual-energy X-ray absorptiometry. Isokinetic knee joint strength was measured by Cybex 770-NORM. All statistical analyses were performed by SAS 9.2. Means and standard deviations were calculated using descriptive statistics. One-way analysis of variance was applied to evaluate nutritional intake, body composition, bone mineral density, and isokinetic strength differences. Duncan multiple range test was used for post hoc testing. A level of significance was set at P<0.05. The study results indicated no significant differences in nutritional in-take among dancer types. Despite no significant differences in body composition among dancer types, contemporary and ballet dancers had lower body fat percentages than controls (P<0.05). No significant differences were seen in bone mineral density and bone mineral contents among dancer types. No significant differences were found in isokinetic strength in right or left knee flexion and extension at 60°/sec (P<0.05). There were significant differences in body composition and isokinetic strength between dancer groups and the control group. Further studies of different professional dance type and more scientific methods of dance training are needed.