Yun-A Shin

Exercise training improves the antioxidant enzyme activity with no changes of telomere length

The purpose of this study was to determine the changes of both oxidant and antioxidant levels with exercise training in obese middle-aged women. The association between telomere length and oxidative stress with exercise was also examined. Sixteen obese middle-aged women participated in this study. The subjects were randomly divided into exercise group (EX) and control group (CON). EX performed aerobic exercise training for 6 months. DNA was extracted from leukocytes in peripheral blood and their telomere lengths were measured by real time PCR analysis. Long-term exercise training decreased body weight and BMI, and increased VO2 max. Resting levels of erythrocyte glutathione peroxidase activity were higher in EX compared to CON. Superoxide dismutase (SOD) activities were higher after the acute exercise test at mid-intensity in post-exercise training than in the pre-exercise training conditions. The telomere length did not change significantly after the acute exercise test in the pre-exercise training condition in spite of the increased level of malondialdehyde (MDA) as a marker of oxidative stress. In conclusion, antioxidant enzyme activities were increased following long-term exercise training; however, the lengths of telomere in leukocytes were not influenced by both mid-intensity and high intensity of exercise stress.

Effect of high-intensity exercise and high-fat diet on lipid metabolism in the liver of rats

[Purpose] This study investigated the effects of high-intensity exercise (Ex) and high dietary fat intake on lipid metabolism in the liver of rats. [Methods] Male Sprague-Dawley rats were randomly assigned to one of the four groups (n=10 per group) that were maintained on a normal diet (ND) or high-fat diet (HFD) consisting of 30% fat (w/w), with or without exercise on a treadmill at 30 m/min and 8% grade) for 4 weeks (i.e., ND, ND+Ex, HFD, and HFD+Ex groups). [Results] Body weight (p<.001), total plasma cholesterol (TC) (p<.001), triglyceride (TG) (p<.05), and liver TG levels (p<.05) were increased in the HFD group relative to the ND groups, and serum glucose (p<.05), insulin (p<.05), homeostatic model assessment of insulin resistance (HOMA-IR) (p<.01), and liver TG levels (p<.01) were also higher in the HFD group compared to the ND+Ex group. Plasma free fatty acid was elevated in the HFD+Ex group compared to the HFD group (p<.01). With the exception of acetyl coenzyme A carboxylase, the expression of lipid metabolism-related genes in the liver was altered in the Ex groups compared to the control group (p<.05), with genes involved in lipolysis specifically up regulated in the HFD+Ex group compared to the other groups. [Conclusion] Vigorous exercise may increase glucose utilization and fat oxidation by activating genes in the liver that are associated with lipid metabolism compared to that in animals consuming a HFD without exercise. Therefore, high intensity exercise can be considered to counter the adverse effects of high dietary fat intake.

Short-term effects of Theracurmin dose and exercise type on pain, walking ability, and muscle function in patients with knee osteoarthritis

The purpose of this study was to investigate the short-term of Theracurmin dose and exercise type on pain, walking ability, and muscle function in patients with knee osteoarthritis. Twenty-five patients with knee osteoarthritis randomly selected to Theracurmin intake (T) group and Theracurmin in combined with exercise (T+E) group. T group (n= 13) was taken orally a capsule of 700 mg, 3 times per day, (total 2,100 mg, 35 mg/kg-body weight). T+E group (n= 12) performed aerobic training of 30-min walking and weight training for increasing leg muscular strength. After treatment, the number of steps, muscle mass, range of motion of knee, and the muscle strength in flexion and extension significantly increased. The percent body fat, visual analogue scale, The Western Ontario and McMaster score, centers of pressure with closed eye, 10-m walking ability, stair ascending speed were significantly decreased after treatment. Although no difference observed between the T and T+E groups, the 4-week intake of Theracurmin with and without exercise appeared to be effective in reducing the pain and enhancing muscular and balancing function. Therefore, Theracurmin intake for early symptoms and additional exercise as symptoms alleviate might be an effective way of delaying and managing osteoarthritis, and additional studies investigating the effects of Theracurmin and exercise on osteoarthritis could be beneficial.

Up-regulation of lipolysis genes and increased production of AMP-activated protein kinase protein in the skeletal muscle of rats after resistance training

The purpose of this study was to investigate the expression of lipogenesis- and lipolysis-related genes and proteins in skeletal muscles after 12 weeks of resistance training. Sprague-Dawley rats (n=12) were randomly divided into control (resting) and resistance training groups. A tower-climbing exercise, in which rats climbed to the top of their cage with a weight applied to their tails, used for resistance training. After 12 weeks, rats from the resistance training group had lower body weights (411.66±14.71 g vs. 478.33±24.63 g in the control), there was no significant difference between the two groups in the concentrations of total cholesterol, and high or low density lipoprotein cholesterol. However, the concentration of triglyceride was lower in resistance-trained rats (59.83±14.05 μg/mL vs 93.33±33.89 μg/mL in the control). The mRNA expression levels of the lipogenesis-related genes sterol regulatory element binding protein-1c, acetyl-CoA carboxylase, and fatty acid synthase were not significantly different between the resistance-trained and control rats; however, mRNA expression of the lipolysis-related carnitine palmitoyl transferase 1 and malonyl-CoA decarboxylase increased significantly with resistance training. AMP-activated protein kinase protein levels also significantly increased in resistance training group compared with in the control group. These results suggested that resistance exercise training contributing to reduced weight gain may be in part be due to increase the lipolysis metabolism and energy expenditure in response to resistance training.

Comparison of tests for measuring maximal exercise ability in elite swimmers.

The purpose of this study was to compare of tests for measuring maximal exercise ability in elite swimmers. The high-school male elite swimmers (n=17) were performed maximal exercise ability tests. The experimental method consisted of a crossover design at 1-week intervals with the swimming tests (field test, water VAMEVAL test, 200-m test, and 400-m test) in random order. It measured the heart rate, ratings of perceived exertion (RPE), and lactate level by physiological factors, and swimming velocity (SV), stroke rate (SR), and stroke length (SL) by mechanical factors. The change of SV, SR, and SL in swimming tests was no significantly different. To compare tests, however, the lactate level and RPE in 200-m test was higher than water VAMEVAL test. The RPE of the 200-m and 400-m tests were higher than the field test and the water VAMEVAL test. Correlations showed between the field test and the 400-m test in heart rate and RPE. Moreover, a correlation observed between the field test and 200-m test in heart rate. In this study, 200-m and 400-m tests were suit to apply the test methods for establishing the exercise intensity appropriate for the underwater training of swimmers.