A comparative analysis of the physical fitness profile of Korean women's national amateur boxers by weight category.

The purpose of this study was to examine the differences in specific physical fitness of the national amateur women's boxer. The Korean women's national amateur boxers were classified into the lightweight category (LWC, n=21) and middleweight category (MWC, n=13), and body composition (percentage body fat and body mass index) and specific physical fitness (maximal muscle strength, anaerobic power, isokinetic muscle strength, cardiopulmonary endurance) were measured. The Mann-Whitney U-test was conducted to determine the differences in the body composition and specific physical fitness in women's boxers. The percentage body fat (P=0.004) and body mass index (P<0.001) were significantly higher in the LWC compared to MWC. In addition, LWC showed significantly higher isokinetic muscle strength (P<0.001), upper anaerobic mean power (P=0.002), maximal muscle strength (P=0.003), and maximal heart rate at anaerobic threshold (P=0.029), maximal oxygen consumption (P<0.001) and the 20-m shuttle-run exercise (P=0.004) compared to MWC. In conclusion, the body fat percentage and body mass index levels among body composition were significantly higher in the MWC than in the LWC, and the constant muscle strength, maximum muscle strength, and cardiopulmonary endurance levels were significantly higher in the LWC than in the MWC. The results of this study are expected to provide useful data for planning future strategies for efficient and scientific training programs for each weight category.

Percent Body Fat Cut-Off Points for Diagnosing Metabolic Syndrome in Korean Adolescents.

BACKGROUND: This study aimed to identify percent body fat cut-off points related to metabolic syndrome in a large sample of Korean adolescents. METHODS: The subjects (n=2120; boys=1107, girls=1013) were middle and high school students aged 12-17 yr who participated in the Korean National Fitness Award Project in 2013. Percent body fat was estimated via eight-polar bioelectrical impedance analysis. Metabolic syndrome was classified using established standards based on the National Cholesterol Education Program with the definition modified for age. Age- and sex-specific percent body fat z-scores were calculated for every adolescent using skewness, median, and coefficient of variation curves to account for growth and development. Receiver operating characteristic curve analysis was used to identify the percent body fat cut-off points using percent body fat z-scores from skewness, median, and coefficient of variation curves as the test and metabolic syndrome as the criterion. RESULTS: Based on the modified National Cholesterol Education Program criteria for metabolic syndrome, the areas under the receiver operating characteristic curve for percent body fat were 0.882 and 0.893 for boys and girls, respectively. The percent body fat percentiles were 82.2 and 87.3 for boys and girls, respectively. According to the skewness, median, and coefficient of variation curves, the percent body fat cut-off points based on the modified National Cholesterol Education Program criteria were 23.6%-25.7% for boys and 32.8%-37.3% for girls, both aged 12-17 yr. Age- and sex-specific percent body fat cut-off points were identified in relation to the metabolic syndrome status of Korean adolescents. CONCLUSION: These percent body fat cut-offs might be useful for identifying metabolic abnormality due to obesity in Korean adolescents.

The effects of 10 weeks of ß-alanine supplementation on peak power, power drop, and lactate response in Korean national team boxers.

This study was designed to investigate the effects of ß-alanine (BA) supplementation on peak power, power drop, and lactate response in elite male amateur boxers. Nineteen male Korean national team boxers were divided into groups with either BA (n=9) or placebo (PL, n=10) supplementation. BA consumed 4.9-5.4 g/day of BA with training for 10 weeks and PL took PL in a similar manner. Physical fitness and lactate changes in sparring were measured before and after the 10-week intervention. Significant interactions (P<0.05) were shown for lower body peak power (P=0.049) and upper body power drop (P=0.042). Positive effects for the BA group were shown for lower body peak power (Cohen d=0.72; 95% confidence interval [CI], 0.09-1.35) and the maintenance of upper body power output (d=-0.91; 95% CI, -1.61 to -0.17). These findings suggest that Korean national amateur boxers who consumed BA demonstrated differential responses following a training intervention in specific physical fitness when compared to boxing athletes who consumed a PL.

Effects of 16-week functional movement screen training program on strength and flexibility of elite high school baseball players.

Functional Movement Screen (FMS) is a way to pretest functional movement. This study examined the effects of the FMS training program on the strength and flexibility of 62 elite male high school baseball players (31 in the training group, 31 in the control group). All players who received less than two points on each FMS test item had to join the 16-week, three times weekly FMS training program. To analyze results among the FMS participants, measures including intraclass correlation coefficient (ICC) and repeated measure ANOVA were utilized. The Kappa coefficient was 0.805 when the intraclass correlation coefficient of the three participants was inspected. Strength showed a significant interaction depending on time and group (hand grip strength: P=0.011, bench press and squat both for one-repetition maximum (1RM): P=0.001 and P=0.008, respectively). Back muscle strength did not show a significant difference (P=0.660). Trunk forward flexion showed no interaction depending on time and groups (P=0.983) but trunk extension backward showed significant differences depending on groups (P=0.004) and time (P=0.001). Splits showed a significant difference depending on time and groups (P=0.004). The FMS training program improved the strength and flexibility of elite high school baseball players.

Salivary cortisol and immunoglobulin A responses during golf competition vs. practice in elite male and female junior golfers.

The purpose of this study was to investigate the stress and immune responses to a competition in elite male and female junior golfers. Six male (16.2 +/- 1.4 years) and 6 female junior golfers (16.4 +/- 1.1 years) completed salivary collections during competition vs. practice rounds on 2 different days. Salivary samples were collected on 4 occasions (rest, before, during, and after rounds). Salivary cortisol and IgA were measured for stress and immune responses, respectively. Our results were as follows: (a) Salivary cortisol level was higher in competition than practice in male golfers (p = 0.009) but it was similar in female golfers. In male golfers, salivary cortisol level was higher before a round than at rest (p = 0.029), but it was higher after rounds than at rest (p = 0.016) in female golfers. (b) Salivary IgA was elevated during competition than during practice rounds in male golfers (p = 0.019), but not in females (p = 0.152). Salivary IgA was not significantly different among salivary collection times although it tended to be elevated during and after rounds for both male and female golfers. In conclusion, salivary cortisol and IgA were elevated during golf competition compared with practice in male junior golfers, but they were not in female golfers. Furthermore, salivary cortisol was higher before a round than rest in men, but it was higher after a round than rest in women. Both male and female junior golfers, however, showed similar salivary IgA responses during golf. Our results suggest that sex might play a role on stress and immune responses during a game of golf in elite junior golfers.