• Journal of Technologic Dentistry
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• v.33 no.3
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• pp.193-202
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• 2011

Purpose: The aim of this study was to evaluate the effect of pre-treatment of core and hydrothermal treatment on the bond strength and flexural strength of ceramic veneered zirconia. Methods: 3Y-TZP specimens(KaVo Zr, $25mm{\times}3mm{\times}1mm$)were prepared by five pre-treatment methods and divided into seven groups including control two groups, subsequently the specimens veneered with the E-MAX ceram according to manufacturer's information(total specimen thickness 1.5mm). Two groups from ceramic-zirconia specimens(n=105, n=15 per group)were assigned into two experimental fatigue conditions, namely storage in an autoclave at $134^{\circ}C$ for 5h, thermo-cycling(3,000cycles, between 5 and $55^{\circ}C$, dwell time 45s, transfer time 2s). A flexural strength test was performed in a universal testing machine(crosshead speed: 0.5mm/min). Data were statistically analyzed using one-way ANOVA and Tukey's test(${\alpha}$=0.05). Results: The ceramic-zirconia bond strength value for liner application group(LLW, $27.3{\pm}3.8$) were significantly lower than those of the pre-treatment groups($30.72{\pm}5.3$). The ceramic-zirconia bond strength and zirconia flexural strength was not affected by thermo-cycling(p>0.05), whereas it was affected by storage in an autoclave at $134^{\circ}C$ for 5h(p<0.05). Conclusion: The results indicated that the ceramic-zirconia bond strength and zirconia flexural strength was affected by low temperature degradation.

• Journal of Digital Convergence
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• v.14 no.4
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• pp.479-486
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• 2016

The purpose of this study was to investigate effects of 12-week physical activity intervention on obesity and metabolic syndrome risk factors and smartphone game time in children. A total of 27 children(fifth grade elementary school students) participated in this study. The subjects were divided to exercise group(n=16) and control group(n=11), and participants in exercise group performed running and jump rope(60min/day; 3days/week; 50~70% of THR) during 12-week. We analyzed measurement data using two-way ANOVA. As results, obesity indices except body weight and metabolic syndrome risk factor decreased significantly in exercise group compare with control group. And VO2max increased and smartphone game time decreased significantly in exercise group compare with control group. In conclusion, we suggest that 12-week exercise intervention in children has positive effects on obesity and metabolic syndrome and improve negative lifestyle such as smartphone game.

• Journal of the East Asian Society of Dietary Life
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• v.15 no.6
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• pp.675-686
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• 2005

It is known that appropriate exercise changes body composition and improves coronary artery disease. This study was undertaken to evaluate the relationships between aerobic exercise, body composition, and the blood lipid levels in the middle-aged women(33 to 54 years old). The 57 subjects were divided into two groups based on their exercise: the aerobic exercise group(A group: 44) which performed at about $60\%$ of $VO_2max$ during over 6 months and the sedentary one(S group: 13). The percentages of body fat waist/hip ratio(WHR), body mass, and lean body mass of two groups were measured and compared in serum HDLC level and oxidized LDL level, the two most effective factors of coronary artery disease. The subjects in A group showed the lower percentages of body fat and WHR, when compared with the ones in S group. The body mass and lean body mass of A group subjects were higher than those of S group subjects. The serum HDL-C level$(58.6\pm12.7mg/mL)$ was significantly higher for A than S group subjects.(p<0.05) The sem ox-LDL level $(6.64\pm4.11Eu/mL)$ for A group subjects was lower than S group ones. The fat mass showed significantly positive correlations with atherogenic index(AI)(r=0.301, p<0.05), and with blood glucose levels(r=0.334, p<0.05). Also the WHR whowed significantly positive correlations with LDL-C levels(r=0.277, p<0.05), and with AI(r=0.466, p<0.01). In summary, the subjects in A group have the lower percentages of body fat and WHR, when compared with the ones in S group. Also, A group subject showed a tendency that exercise enhances serum HDL-C levels and decreases oxidized LDL levels. And aerobic exercise showed positive results which change body composition and improve blood lipid levels. There were significantly positive correlations among the percentages of body fat At and blood glucose level. These results suggest that moderately intensive exercise is a significant factor in reducing coronary artery disease.

• Fashion & Textile Research Journal
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• v.8 no.3
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• pp.349-356
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• 2006

The purpose of this study was to compare the thermophysiological responses and subjective sensations of clothing materials with different water transfer property investigated in exercising and resting subjects at an ambient temperature of $20^{\circ}C$ and a relative humidity of 40%. Two kinds of clothing ensemble were tested: 100% cotton with highly water-absorbent but slowly dry properties(C) and 100% polyester with quickly water-absorbent and dry properties by four capillary channels(QADP). Seven apparently healthy male participants each undertook two series of experiments comprised 10-min of rest, 20-min of exercise with 70% of $VO_{2max}$ on a treadmill and 20-min of recovery. Mean skin temperature was significantly lower in QADP than in C during exercise and recovery. Clothing microclimate temperature was significantly lower in QADP during exercise and clothing surface temperature was also lower in QADP especially during recovery. Also, clothing surface humidity was significantly higher in QADP after the later half of exercise. The concentration of blood lactic acid tended to decrease to a lower level at recovery 3 minutes when wearing QADP rather than C clothing ensemble. Metabolic energy was marginally significantly less during the second half of exercise in QADP. Body mass loss tended to be greater in C than in QADP. The participants had better scores in thermal sensation, comfortable sensation and wetness in QADP during exercise and recovery. These results show that functional materials with quickly water-absorbent and dry properties can alleviate heat strain and induce more comfortable clothing microclimates and subjective sensations in the exercise-induced hyperthermia.

• Preventive Nutrition and Food Science
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• v.18 no.3
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• pp.175-180
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• 2013

The purpose of this study was to determine the effects of a pre-exercise meal on the plasma human growth hormone (hGH) response and fat oxidation during walking. Subjects (n=8) were randomly provided with either 1 g/kg body weight of glucose in 200 mL water (CHO) or 200 mL water alone (CON) 30 min prior to exercise and subsequently walked on a treadmill at 50% of VO2max for 60 min. Plasma hGH concentrations were significantly higher in subjects who received CHO compared to those who received CON at 15 and 30 min. The fat oxidation rate in the CHO was significantly lower than the CON while walking for 5~15, 25~35 and 45~55 min. Plasma FFA levels were also significantly lower in the CHO compared to the CON at 30, 45 and 60 min. Plasma glucose levels in the CHO were significantly lower while plasma insulin levels were significantly higher than in the CON at 15 and 30 min. Therefore, the results of this study suggest that the elevation of plasma hGH levels due to the intake of a pre-exercise meal may not be strongly related to fat oxidation and plasma free fatty acid (FFA) levels during low-intensity exercise.

• The Journal of Korean Physical Therapy
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• v.29 no.5
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• pp.281-286
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• 2017

Purpose: The purpose of this study was to examine the correlations among the resting physical factors related to a six-minute walk test (6MWT) and to determine the effects of the resting physical factors on the distance and intensity related to the 6MWT in healthy female subjects. Methods: A total of 43 healthy female subjects ($22.84{\pm}3.90yrs$) participated in this study. They performed the 6MWT, and the physical factors related to the 6MWT were assessed. SPSS 20.0 was used to analyze the data, and the mean and standard deviation were calculated, and the collected data were analyzed by the Pearson's correlation coefficient (among physical factors related to 6MWT) and independent t-test (between six-minute walk distance [6MWD] groups and six-minute walk intensity [6MWI] groups). Results: The 6MWD had a significant negative correlation with the resting HR (beat/min) in healthy female subjects (r=-0.49, p<0.05). The 6MWI had a significant negative correlation with the resting systolic blood pressure (SBP) (r=-0.45, p<0.01). A comparison of the 6MWD revealed the long distance group (LDG, 700-799 m) to be significantly higher than the middle distance group (MDG, 600-699 m) in the 6MWI (%), %predicted distance (%), predicted VO2max (mL/kg/min), resting HR (beat/min), and resting SBP (mmHg)(p<0.05). In the comparison of 6MWI, the moderate intensity group (MIG, 64-75%HRmax) was significantly lower than the low intensity group (LIG, 50-63%HRmax) in the resting SBP (mmHg) (p<0.05). Conclusion: These results suggest that the resting physical factors are related to the 6MWD and 6MWI of the 6MWT in healthy females. In particular, SBP is associated with not only the 6MWD but also the 6MWI in 6MWT.

• Journal of Life Science
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• v.13 no.4
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• pp.448-456
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• 2003

The purpose of this study was to determine changes in their cardiorespiratory function and body composition in female workers after aerobic exercise and circuit weight training. The subjects of this study were 16 female workers in B city and was divided into exercise and control groups which were composed of 8 people respectively. The members of exercise group had aerobic exercise and circuit weight training an hour a day, 5 days per week, for 8 weeks while controled group did not. Both groups were pretested and posttested, and the results of this study on cardiorespriatory function and body composition are as follows. Exercise group showed significant decrease in heart rate at rest(p<.001). Exercise group showed significant increase in the oxygen uptake at rest, in the maximum oxygen uptake and in the vital capacity(p<.001). Exercise group showed significant decrease in the %fat and fat(p<.001). Exercise group showed significant increase in the %LBM and LBM(p<.001).

• Korean Journal of Exercise Nutrition
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• v.13 no.1
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• pp.75-81
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• 2009

This study aims to find out the effect of ingestion of 3 mg·kg^-1 caffeine on fluid-electrolyte balance and Tty change during exercise under heat environment of 30~32℃ (40-50% humidity). Five trained males who routinely trained for approximately 60 min·d^-1, 3-6 d·wk^-1 (age; 28.20±3.56yrs, height; 174.56±5.46 cm, body mass; 76.13±9.02 kg, body fat(%); 14.24±3.99, VO₂max; 54.00±4.30 mL·kg^-1·min^-1, exercise career; 4.20±1.95yrs) performed 40min of treadmill running in heat chamber. The study was a double-blind, randomized, crossover design. Body mass change following exercise was higher for the PLAC (Placebo) and CAFF (Caffeine) in comparison to the CON (Control), there was no significant difference between the CAFF, PLAC, CON (p= .997). The U_sg not significant differences (p= .731) and Osm_urine not significant differences between the CAFF, PLAC, CON (p= .901). There also were not significant between the CAFF, PLAC, CON for [Na⁺]_urine and [K⁺]_urine (p= .928, p= .469). In the case of Tty, although the increase rate of Tty was the highest for the CAFF on exercise early, exercise the second half in comparison to the CON and PLAC, there was not significant interaction effect between the CAFF, PLAC, and CON of Tty (p= .067), In conclusion, it was confirmed that the 3 mg·kg^-1 caffeine ingestion prior to exercising in heat environment does not impart negative effect on body fluid, electrolyte balance and changes in Tty.

• 한국체육학회지인문사회과학편
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• v.54 no.1
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• pp.553-566
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• 2015

This study was performed to identify the effects of different intensities of regular aerobic exercise on erythropoietin (EPO) and BDNF levels, and cognitive function and working memory in middle-aged women. Women aged 40 to 60 years residing in G-gu, Y-si, Gyeonggi-do were divided into 3 groups: control group, moderate-intensity aerobic exercise group and high-intensity aerobic exercise. All groups were asked to exercise at the given intensities, twice a week for a total of 12 weeks. Blood samples were collected from participants on week 0 (before exercising), week 6 and week 12, and then cognitive function and working memory tests were followed to measure erythropoietin (EPO) and BDNF levels, cognitive function and working memory. Repeated measures ANOVA, univariate analysis and follow-up test were performed on all data to compare the group, period and interaction through a SPSS. As a result, a significant difference over time was observed in EPO, BDNF, cognitive function and working memory; therefore, a follow-up one-way ANOVA analysis was performed on each group. As a result of analysis, a significant increase in erythrocyte, hematocrit, BDNF level and working memory was observed in moderate-intensity aerobic exercise group while erythrocyte and working memory were significantly increased inhigh-intensity aerobic exercise group. When comparing the results between the groups, the level of hematocrit was shown to be significantly higher in both moderate-and high-intensity aerobic group than the control group and also the higher level of hemoglobin was observed in both moderate-and high-intensity aerobic group comparing to control group. Considering the results of this study, therefore, a 12-week long aerobic exercise at moderate to high intensity positively affected EPO and BDNF levels, cognitive function and working memory in middle-aged women.

• Journal of Life Science
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• v.19 no.6
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• pp.804-808
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• 2009

The purpose of the this study was to examine the effects of 12 weeks of regular aerobic exercise training on hepatic enzymes in type 2 diabetes mellitus (T2DM) patients. The subjects consisted of 13 middle-aged male type 2 diabetes mellitus (T2DM) patients, all of whom had no other complications. Subjects participated in regular aerobic exercise training for 12 weeks, in which they started to exercise for $20{\sim}60$ min, at $60{\sim}80$% $HR_{max}$ (exercise intensity was increased gradually), per day, $3{\sim}5$ times a weeks. The results after 12 weeks were compared to baseline values. Weight and BMI, %body fat, and fasting glucose significantly decreased, and $_{peak}VO_{2}$, exercise time (ET) significantly increased after 12 weeks of aerobic exercise training. On the other hand, there were no significant differences in hepatic enzymes of Albumin, Total bilirubin, Alkaline phosphatate, AST, and ALT after training compared to baseline values. Conclusively, 12 weeks of aerobic exercise training may result in a decrease of insulin resistance factors (Weight, BMI, % body fat, fasting glucose) and an increase of aerobic capacity, but hepatic enzymes did not significantly decrease in middle age T2DM patients.