ABSTRACT
PURPOSE: The objective of this study was to investigate the effects of plyometric training on physical fitness and muscle damage in high school baseball players. METHODS: The participants in the study included 21 high school baseball players who are healthy and well-training. The participants were randomly allocated to the plyometric training (n=11) and control (n=10) groups. The plyometric training was applied 3 times a week for a total of 8 weeks and the control group took part in only regular baseball skills training without plyometric training. For physical fitness, measures included maximal strength (left and right hand-grip strength), muscle endurance (sit-up), agility (side-step), power (standing long jump), and balance (left and right Rhomberg test). For muscle damage, creatine kinase (CK) and lactate dehydrogenase (LDH) levels were measured. RESULTS: The results showed a significant interaction effect between time and groups in left hand-grip strength (P = 0.022), side-step (P = 0.004), and standing long jump (P < 0.001) after the 8-week plyometric training, with greater improvement in the plyometric training group than the control group. On the other hand, there was no significant interaction effect between time and groups in right hand-grip strength, situp, left and right Rhomberg test, CK level, and LDH level (P > 0.05). CONCLUSION: In conclusion, 8-week plyometric training had a positive effect on improving physical fitness, such as maximal strength, agility, and power, in high school baseball players without causing additional muscle damage.
ABSTRACT
BACKGROUND: There have been few recent reports on the methodological quality of meta-analysis, despite the enormous number of studies using meta-analytic techniques in the field of anesthesia. The purpose of this study was to evaluate the quality of meta-analyses and systematic reviews according to the Assessment of Multiple Systematic Reviews (AMSTAR) and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines in the anesthesia literature. METHODS: A search was conducted to identify all meta-analyses ever been published in the British Journal of Anaesthesia (BJA), Anaesthesia, and Korean Journal of Anesthesiology (KJA) between Jan. 01, 2004 and Nov. 31, 2016. We aimed to apply the AMSTAR and PRISMA checklists to all published meta-analyses. RESULTS: We identified 121 meta-analyses in the anesthesia literature from January 2004 through the end of November 2016 (BJA; 75, Anaesthesia; 43, KJA; 3). The number of studies published and percentage of 'Yes' responses for meta-analysis articles published after the year 2010 was significantly increased compared to that of studies published before the year 2009 (P = 0.014 for Anaesthesia). In the anesthesia literature as a whole, participation of statisticians as authors statistically improved average scores of PRISMA items (P = 0.004) especially in the BJA (P = 0.003). CONCLUSIONS: Even though there is little variability in the reporting and methodology of meta-analysis in the anesthesia literature, significant quality improvement in the reporting was observed in the Anaesthesia by applying the PRISMA checklist. Participation of a statistician as an author improved the reporting quality of the meta-analysis.
ABSTRACT
[Purpose] We investigated whether waist and mid-thigh circumference correlated with cardiovascular fitness (VO2max) in a selected sample of Korean college students. [Subjects and Methods] The subjects were 41 college students (25 males, 16 females; age, > 19â years) who visited the sports medicine laboratory at the Korea National University of Transportation in Chungju-si, Republic of Korea, to undergo measurements of body composition, cardiovascular fitness, and waist and mid-thigh circumference. [Results] VO2max did not correlate with waist circumference or mid-thigh circumference in males, whereas VO2max was negatively correlated with mid-thigh circumference, but not waist circumference, in females. [Conclusion] Mid-thigh circumference was not associated with cardiovascular fitness or waist in male college students. However, it was associated with cardiovascular fitness in female college students. Well-designed studies are needed to investigate this further.
ABSTRACT
Menopause is associated with an increased risk of cardiovascular disease (CVD). Exercise and soy isoflavone diets have been suggested to reduce the risk of CVD in postmenopausal women. We investigated the effects of exercise, or combined exercise and soy isoflavone diet, on plasma lipid profiles, paraoxonase (PON), nitric oxide (NO) and apoptosis in the aorta of ovariectomized (OVX) rats. Thirty-two female Sprague-Dawley rats were divided into four groups: OVX with general diet (OVX-GD), OVX with isoflavone diet (OVX-ISO), OVX-GD with exercise training (OVX-ET) and OVX-ISO with exercise training (OVX-ISO+ET). The experimental rats undertook treadmill training (30 min/day, 4 days/week) and/or were supplied a soy isoflavone diet (added to the experimental diet at 2.39 mg/g protein) for 12 weeks. Body weight and levels of total cholesterol (TC), triglyceride (TG), LDL-cholesterol (LDL-C) increased in the OVX rats and HDL-C decreased. These effects were reduced by exercise and/or soy isoflavone supplementation. PON and NO activities were higher in the OVX-ISO+ET group than in the OVX-GD group. In addition, this group had lower caspase-9 and -3 and higher Bcl-2 expression, and there was less aortic apoptotic cell death. These results suggest that a combination of exercise and a soy isoflavone diet has beneficial effects in terms of protecting against cardiovascular risk factors by controlling lipid profiles and the related enzyme, PON, as well as NO activity and apoptosis of the aorta in OVX rats.
