The Psychometric Characteristic of the Taekwondo Electronic Protector Cognition Scale: The Application of the Rasch Model.

This research was to investigate the psychometric characteristics of the electronic protector cognition scale by the infit and outfit of taekwondo athletes. Methods: The research tools utilized the existing research of Jeon Ik-ki (2008), which conducted a survey of male and female athletes of 19 participating countries at the 19th Taekwondo World Championships. The electronic protector cognition scale used a five-point Likert grading with 1 (not at all) to 5 (very likely). Analysis using IBM SPSS STATISTICS version 23 (IBM SPSS, Inc., Chicago, IL, USA) was conducted for the 226 data sets collected. WINSTEPS 3.74 (Linacre, 2015) was used for calculating subject reliability, item goodness-of-fit, scale propriety, and item level of difficulty, in order to apply the item response theory to the psychometric characteristics of electronic protectors. The research results showed that it was suitable for subject infit/outfit in taekwondo electronic protector cognition scale as 1.00~1.01 and the input/output of taekwondo electronic protector cognition scale as 1.00~1.01. Secondly, five-point scales were reviewed to be suitable for scale propriety, resulting from stage index judgment. Thirdly, 8 items showed problems in item goodness-of-fit. Finally, scale propriety was reported to be suitable considering the ability distribution of taekwondo players and the level of scale difficulty.

The combined impacts of docosahexaenoic acid, endurance physical exercise, and prolonged fasting on brain function.

Docosahexaenoic acid (DHA), a long chain polyunsaturated fatty acid (PUFA) is highly enriched in the membrane phospholipids of the brain, neuronal tissue and retina. Accumulating evidence suggests that brain DHA is necessary for maintaining for optimal function of the cognition and the visual system, particularly the photoreceptor, the retina. Loss of brain DHA, especially during crucial brain development period, was highly associated with visual and cognitive defects. Here it would be addressed the effect of DHA on brain functions as assessed by spatial task performance using a first generation model which is similar to human nutrition case. And also, it was well known that prolonged fasting and energy restriction with endurance physical exercise stimulate cognitive function and brain function, which is caused by upregulated ketone body and upregulated brain-derived neurotropic factor (BDNF) responses. In the DHA intake or prolonged physical exercise, upregulated BDNF can activate mitochondrial biogenesis to elevate neuronal bioenergetics and enable synaptic formation. And it also can activate DNA repair in neurons. Further study on the mechanisms about the combine effects of supplementation of DHA and energy restriction on brain function is urgently needed in this area.

Yoga training improves metabolic parameters in obese boys.

Yoga has been known to have stimulatory or inhibitory effects on the metabolic parameters and to be uncomplicated therapy for obesity. The purpose of the present study was to test the effect of an 8-week of yoga-asana training on body composition, lipid profile, and insulin resistance (IR) in obese adolescent boys. Twenty volunteers with body mass index (BMI) greater than the 95th percentile were randomly assigned to yoga (age 14.7±0.5 years, n=10) and control groups (age 14.6±1.0 years, n=10). The yoga group performed exercises three times per week at 40~60% of heart-rate reserve (HRR) for 8 weeks. IR was determined with the homeostasis model assessment of insulin resistance (HOMA-IR). After yoga training, body weight, BMI, fat mass (FM), and body fat % (BF %) were significantly decreased, and fat-free mass and basal metabolic rate were significantly increased than baseline values. FM and BF % were significantly improved in the yoga group compared with the control group (p<0.05). Total cholesterol (TC) was significantly decreased in the yoga group (p<0.01). HDL-cholesterol was decreased in both groups (p<0.05). No significant changes were observed between or within groups for triglycerides, LDL-cholesterol, glucose, insulin, and HOMA-IR. Our findings show that an 8-week of yoga training improves body composition and TC levels in obese adolescent boys, suggesting that yoga training may be effective in controlling some metabolic syndrome factors in obese adolescent boys.

Combined effects of swim training and ginseng supplementation on exercise performance time, ROS, lymphocyte proliferation, and DNA damage following exhaustive exercise stress.

The purpose of this study was to analyze the combined effects of regular exercise and ginseng supplementation on peritoneal exudate ROS (reactive oxygen species), lymphocyte proliferation by splenocytes, and DNA damage following exhaustive exercise stress. Thirty-six female BALB/c mice were randomly divided into control (UT, n = 12), trained (TR, n = 12), and ginseng supplemented and trained (GT, n = 12) groups. Each group was divided into two equal subgroups where mice were studied at rest (UTre, TRre, and GTre) or immediately after exhaustive exercise stress (UTex, TRex, and GTex). Animals were bred in the animal facility, where they were housed at 22-24 degrees C and relative humidity (RH) 50-60% in a controlled environment with a 12-hour photoperiod, and provided food and water ad libitum. The trained mice underwent 10 weeks of endurance swim training (5 times/week) in water at 27-30 degrees C for 60 minutes. The analytical items examined were weight, proliferative activity, the production of ROS from peritoneal exudate cells, and DNA damage following exhaustive exercise stress (2 h exercise stress). Significant level was set at p < 0.05. The results obtained showed that the trained group had a significantly lower mean body weight than the untrained group (p < 0.05). However, there was no significant difference between UT and GT. Swim training increased swim survival time in TRex and GTex, and TRex showed the highest swim survival time. With regard to mitogenic activities of splenocytes in response to exhaustive exercise stress, all groups showed much lower lymphocyte proliferative activity when stimulated with media (Med), concanavalin A (ConA), or lipopolysaccharide (LPS) after exhaustive exercise stress. However, GTex had a higher proliferative activity than the other groups. Trained and ginseng-supplemented groups showed lower peritoneal ROS responses and lymphocyte DNA damage levels after exhaustive exercise. These findings suggest that the combined effect of swim training and ginseng supplementation sustain lymphocyte function in the presence of reduced ROS production and DNA damage following acute exercise stress.