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[Purpose] We compared and analyzed energy consumption and excess post-exercise oxygen consumption (EPOC) following Taekwondo Taegeuk Poomsae performances.[Methods] Forty-two healthy men who could perform Taegeuk Poomsae 1–8 Jangs were enrolled in this study. To reduce the impact of Poomsae, a random cross-design was used. The washout time was set to at least three days. Oxygen consumption (VO2) was monitored after performing each Poomsae until a reference line was resumed. Each Taegeuk Poomsae was performed at a speed of 60 bpm.[Results] There was no significant difference in VO2, carbon dioxide excretion, and heart rate after performing the Taegeuk Poomsae once; however, all variables increased significantly in combined results of EPOC metabolism (Fp2p2

[Purpose] Although several physiological roles of lactate have been revealed in the last decades, its effects on energy metabolism and substrate oxidation remain unknown. Therefore, we investigated the effects of lactate on the energy metabolism of resting rats.[Methods] Male rats were divided into control (Con; distilled water), caffeine (Caf; 10 mg/kg), L-lactate (Lac; 2 g/kg), and lactate-plus-caffeine (Lac+Caf; 2 g/ kg + 10 mg) groups. Following oral administration of supplements, resting energy expenditure (study 1), biochemical blood parameters, and mRNA expression involved in energy metabolism in the soleus muscle were measured at different time points within 120 minutes of administration (study 2). Moreover, glycogen level and Pyruvate dehydrogenase (PDH) activity were measured.[Results] Groups did not differ in total energy expenditure throughout the 6 hour post-treatment evaluation. Within the first 4 hours, the Lac and Lac+Caf groups showed higher fat oxidation rates than the Con group (p

[Purpose] The purpose of this study was to evaluate the effects of a 12-week non-contact exercise intervention on body composition and health-related physical fitness in adults.[Methods] One hundred adults were initially enrolled; however, ninety-seven participants (men: n = 41, women: n = 56) completed the study. The non-contact exercise was performed for 12 weeks using a smart tracker (Charge 4, Fitbit, USA) and mobile phone applications. The non-contact exercise program included resistance, aerobic, and flexibility exercises.[Results] The results showed that percent body fat (F=4.993, p=.016, ηp2=.049), fat-free mass (F=4.690, p=.024, ηp2=.047), and skeletal muscle mass (F=5.623, p=.004, ηp2=.055) significantly changed during the intervention period. Further, significant increases were seen in hand grip strength (F=12.167, pp2=.112), sit-and-reach (F=20.497, pp2=.176), sit-ups (F=42.107, pp2=.305), and VO2max (F=4.311, p=.037, ηp2=.043).[Conclusion] Our findings suggest that 12 weeks of non-contact exercise improves body composition and health-related physical fitness. Wearable technologies encourage individuals to modify their lifestyles by increasing physical activity and achieving the goal of maintaining health conditions among adults.

[Purpose] This preliminary study aimed to develop a regression model to estimate the non-exercise activity thermogenesis (NEAT) of Korean adults using various easy-to-measure dependent variables. [Methods] NEAT was measured in 71 healthy adults (male n = 29; female n = 42). Statistical analysis was performed to develop a NEAT estimation regression model using the stepwise regression method. [Results] We confirmed that ageA, weightB, heart rate (HR)_averageC, weight × HR_averageD, weight × HR_ sumE, systolic blood pressure (SBP) × HR_restF, fat mass ÷ height2G, gender × HR_averageH, and gender × weight × HR_sumI were important variables in var ious NEAT activity regression models. There was no significant difference between the measured NEAT values obtained using a metabolic gas analyzer and the predicted NEAT. [Conclusion] This preliminary study developed a regression model to estimate the NEAT in healthy Korean adults. The regression model was as follows: sitting = 1.431 - 0.013 × (A) + 0.00014 × (D) - 0.00005 × (F) + 0.006 × (H); leg jiggling = 1.102 - 0.011 × (A) + 0.013 × (B) + 0.005 × (H); standing = 1.713 - 0.013 × (A) + 0.0000017 × (I); 4.5 km/h walking = 0.864 + 0.035 × (B) + 0.0000041 × (E); 6.0 km/h walking = 4.029 - 0.024 × (C) + 0.00071 × (D); climbing up 1 stair = 1.308 - 0.016 × (A) + 0.00035 × (D) - 0.000085 × (F) - 0.098 × (G); and climbing up 2 stairs = 1.442 - 0.023 × (A) - 0.000093 × (F) - 0.121 × (G) + 0.0000624 × (E).

[Purpose] This pilot study aimed to develop a re gression model to estimate the excess post-exercise oxygen consumption (EPOC) of Korean adults using various easy-to-measure dependent variables. [Methods] The EPOC and dependent variables for its estimation (e.g., sex, age, height, weight, body mass index, fat-free mass [FFM], fat mass, % body fat, and heart rate_sum [HR_sum]) were measured in 75 healthy adults ( 31 males, 44 females). Statistical anal ysis was performed to develop an EPOC estimation re gression model using the stepwise regression method. [Results] We confirmed that FFM and HR_sum were important variables in the EPOC regression models of various exercise types. The explanatory power and standard errors of estimates (SEE) for EPOC of each exercise type were as follows: the continuous exercise (CEx) regression model was 86.3% (R2) and 85.9% (adjusted R2), and the mean SEE was 11.73 kcal, interval exercise (IEx) regression model was 83.1% (R2) and 82.6% (adjusted R2), while the mean SEE was 13.68 kcal, and the accumulation of short-duration exercise (AEx) regression models was 91.3% (R2) and 91.0% (adjusted R2), while the mean SEE was 27.71 kcal. There was no significant difference between the measured EPOC using a metabolic gas analyzer and the predicted EPOC for each exercise type. [Conclusion] This pilot study developed a regression model to estimate EPOC in healthy Korean adults. The regression model was as follows: CEx = -37.128 + 1.003 × (FFM) + 0.016 × (HR_sum), IEx = -49.265 + 1.442 × (FFM) + 0.013 × (HR_sum), and AEx = -100.942 + 2.209 × (FFM) + 0.020 × (HR_sum).

[Purpose] Lactate has several beneficial roles as an energy resource and in metabolism. However, studies on the effects of oral administration of lactate on fat metabolism and glycogen synthesis are limited. Therefore, the purpose of the present study was to investigate how oral administration of lactate affects fat metabolism and glycogen synthesis factors at specific times (0, 30, 60, 120 min) after intake. [Methods] Male Sprague Dawley (SD) rats (n = 24) were divided into four groups as follows: the control group (0 min) was sacrificed immediately after oral lactate administration; the test groups were administered lactate (2 g/kg) and sacrificed after 30, 60, and 120 min. Skeletal muscle and liver mRNA expression of GLUT4, FAT/CD36, PDH, CS, PC and GYS2 was assessed using reverse transcription-polymerase chain reaction. [Results] GLUT4 and FAT/CD36 expression was significantly increased in skeletal muscle 120 min after lactate administration. PDH expression in skeletal muscle was altered at 30 and 120 min after lactate consumption, but was not significantly different compared to the control. CS, PC and GYS2 expression in liver was increased 60 min after lactate administration. [Conclusion] Our results indicate that exogenous lactate administration increases GLUT4 and FAT/CD36 expression in the muscle as well as glycogen synthase factors (PC, GYS2) in the liver after 60 min. Therefore, lactate supplementation may increase fat utilization as well as induce positive effects on glycogen synthesis in athletes.

[Purpose] Blood glucose and insulin resistance were lower following hypoxic exposure in previous studies. However, the effect of hypoxia as therapy in obese model has not been unknown. [Methods] Six-week-old mice were randomly divided into chow diet (n=10) and high-fat diet (HFD) groups (n=20). The chow diet group received a non-purified commercial diet (65 % carbohydrate, 21 % protein, and 14 % fat) and water ad libitum. The HFD group was fed an HFD (Research Diet, #D12492; 60% kcal from fat, 5.24 kcal/g). Both groups consumed their respective diet for 7 weeks. Subsequently, HFD-induced mice (12-weeks-old) were randomly divided into two treatment groups : HFD-Normoxia (HFD; n=10) and HFD-Hypoxia (HYP; n=10, fraction of inspired=14.6%). After treatment for 4 weeks, serum glucose, insulin and oral glucose tolerance tests (OGTT) were performed. [Results] Homeostatic model assessment values for insulin resistance (HOMA-IR) of the HYP group tended to be lower than the HFD group. Regarding the OGTT, the area under the curve was 13% lower for the HYP group than the HFD group. [Conclusion] Insulin resistance tended to be lower and glucose uptake capacity was significantly augmented under hypoxia. From a clinical perspective, exposure to hypoxia may be a practical method of treating obesity.

[Purpose] Numerous epidemiological studies have shown that it is possible to prescribe exercise for neurodegenerative disease, such as Alzheimer''s dis­ease and Parkinson’s disease. However, despite the availability of diverse scientific knowledge, the effects of exercise in this regard are still unclear. Therefore, this study attempted to investigate a substance, such as black chokeberry (Aronia melanocapa L.) that could improve the ability of the treatment and enhance the benefits of exercising in neurodegenerative diseases. [Methods] The cell viability was tested with 2,3-bis[2- methyloxy-4-nitro-5-sulfophenyl]-2H-tetrazolim-5- carboxanilide and the cells were stained with ethidium homodimer-1 solution. The mRNA expression levels were evaluated by microarray. The active compounds of black chokeberry ethanolic extract (BCE) were analyzed by gas chromatography. The chemical shift analysis in the brain was performed using magnetic resonance spectroscopy. [Results] BCE treatment decreased hydrogen perox­ide-induced L6 cell death and beta amyloid induced primary neuronal cell death. Furthermore, BCE treatment significantly reduced the mRNA levels of the inflam­matory factors, such as IL-1α, Cxcl13, IL36rn, Itgb2, Epha2, Slamf8, Itgb6, Kdm6b, Acvr1, Cd6, Adora3, Cd27, Gata3, Tnfrsf25, Cd40lg, Clec10a, and Slc11a1, in the primary neuronal cells. Next, we identified 16 active compounds from BCE, including D-mannitol. In vivo, BCE (administered orally at a dosage of 50 mg/ kg) significantly regulated chemical shift in the brain. [Conclusion] Our findings suggest that BCE can serve as a candidate for neurodegenerative disease therapy owing to its cyto-protective and anti-inflamma­tory effects. Therefore, BCE treatment is expected to prevent damage to the muscles and neurons of the athletes who continue high intensity exercise. In future studies, it would be necessary to elucidate the effects of combined BCE intake and exercise.

[Purpose] The purpose of this study was to determine whether different types of carbohydrate diets with or without exercise changes energy metabolism at rest and during exercise. [Methods] To minimize differences in food and energy intake between experimental groups, mice were pairfed. After 1 week of adaptation, 40 male ICR mice (6 weeks old) were randomly divided into four groups: Sta. (high fat + high starch), Scu. (high fat + high sucrose), StaEX. (high fat + high starch + exercise), and SucEX. (high fat + high sucrose + exercise). StaEX. and ScuEX. groups underwent training by running on a treadmill five times a week. After 10 weeks of training, energy metabolism was measured for 24 h and during a 1 h exercise period. [Results] The final body weight showed no significant difference between the groups. However, the weight of abdominal tissues (epididymal, perirenal, and mesenteric adipose tissue) in training groups was markedly decreased following 10 weeks of training. Results of all energy metabolism (24 h at rest and during 1 h of exercise) showed no significant interactions between diet and exercise. A brief summary of the results of the energy metabolism is that the metabolism related indicators over 24 h were more affected by the dietary pattern than the exercise but during the 1 h of exercise, training had more effect on energy metabolism than diet. [Conclusion] Our findings confirm that: (a) the type of carbohydrates included in the diet influence the metabolic responses over 24 h, (b) training had more effect on energy metabolism than diet during 1 h of exercise, (c) both results; abdominal adipose tissue weight and fat oxidation during exercise are suggestive for a beneficial effect of moderate physical activity on weight maintenance.

[Purpose] The purpose of this study was to confirm that the difference in excess post-exercise oxygen consumption (EPOC) during exercise of the spending the same calories between the continuous and interval exercise. [Methods] Thirty-four healthy college students who did not regularly exercise volunteered to participate in our study. Continuous exercise was performed on an ergometer for 30 min at 60% of maximal oxygen consumption (VO2 max). Interval exercise was performed on a cycle ergometer at 80% VO2 max for 2 min initially, followed by 40% VO2 max for 1 min, and 80% VO2 max for 3 min. This was repeated six times for a total of 26 min. [Results] The major findings were as follows: (1) energy consumption during exercise was not significantly different between continuous exercise and interval exercise groups; (2) EPOC was higher in interval exercise than in continuous exercise for all dependent variables (i.e., total oxygen consumption, total calories, summation of heart rate); and (3) there were no significant differences in the lipid profile between continuous and interval groups. [Conclusions] Our study confirmed that after equalizing energy expenditure for continuous and interval exercise on a cycle ergometer in subjects in their twenties, interval exercise results in higher EPOC than continuous exercise. These data suggest that interval exercise may be more effective than continuous exercise in reducing body fat, for a given amount of energy expenditure.

[Purpose] Resistance exercise training (RET) and an additional intake of dietary protein supplements may improve muscle mass and muscular function, and reduce inflammatory markers. The types, amount, and timing of dietary protein supplements are important for the synergistic effects of resistance training and dietary protein supplements. We hypothesized that a 25.1 g protein complex supplement taken for 12 weeks, immediately before and after resistance exercise, would enhance fat free mass and isokinetic muscular function in young untrained males. [Methods] Eighteen participants were randomly assigned to a placebo (n=8) or protein complex supplement groups (n=10). The RET was a supervised progressive program, 3 times per week for 12-weeks, and was performed progressing 80% of their one repetition maximum (1-RM). Body composition, blood pressure, plasma inflammatory markers, lipid level and isokinetic muscular function were assessed before and after the study period. [Results] There was a significant interaction effect in C-reactive protein (CRP) (p =0.044) among blood vessel inflammatory markers. The protein complex supplement group had shown more effective improvement at 12 weeks intervention compared to the placebo group in isokinetic muscular function. There was a significant interaction effect in peak torque at 60 degrees/sec leg extension (p =0.044), total work at 240 degrees/sec leg extension (p =0.025), and total work at 240 degrees/sec leg flexion (p =0.011). [Conclusion] Protein complex supplementation during RET appears more effective than RET alone in improving isokinetic muscular function for 12 weeks in untrained young men.

[Purpose] Physical inactivity behavior at middle age or older is a major risk factor for cardiovascular disease. However, the effects of levels of habitual physical activity on arterial stiffness in elderly population remain unclear currently. Therefore, the purpose of this study was to demonstrate whether the effects of habitual physical activity could attenuate arterial stiffness in elderly individuals via a meta-analysis. [Methods] We searched the Medline and Embase databases from January 1997 through November 2017, using the medical subject headings “older population”, “physical activity” (e.g., walking, cycling, climbing, and any participation in sports), “arterial stiffness”, “pulse wave velocity”, and “cardiovascular health” published in English. Six articles (2,932 participants) were included in this meta-analysis. We investigated the effects of habitual physical activity on arterial stiffness, which was measured by the pulse wave velocity. [Results] Results confirmed heterogeneity (Q-value = 160.691, p = 0.000, I2 = 96.888) between individual studies. The effect size was calculated using random effect model. It has shown that physically active individuals have significantly lower arterial stiffness than their sedentary peers do (standardized mean difference: -1.017 ± 0.340, 95% confidence interval: -1.684 ~ -0.350, p = 0.003). [Conclusion] Findings of our systematic review and meta-analysis indicate that habitual physical activity can significantly ameliorate arterial stiffness in the elderly population.

[Purpose] The purpose of the current study was to investigate steps per day (steps/d) and physical activity level (PAL) in Korean elementary school children having normal weight (normal-weight). We also clarified whether a gender difference exited between steps/d and PAL. [Methods] Children aged 9 to 12 y were recruited from two elementary schools located in different urban districts in Korea. The present study included 33 Korean children, of which 18 were normal-weight boys and 15 were normal-weight girls. During the same 1 week study period under free-living conditions the total energy expenditure (TEE) and step counts were estimated using the doubly labeled water (DLW) method and an accelerometer, respectively. We calculated PAL as the TEE/ resting metabolic rate. [Results] The range of PAL was 1.25 – 1.93 with a mean value of 1.57. None of the variables of energy expenditure was significantly different by sex. However, steps/d were significantly higher in boys than in girls. When adjusting regression analysis by gender, steps/ d were positively associated with PAL among all subjects (r = 0.56, P < 0.01). Furthermore, steps/d were positively associated with PAL in boys (r = 0.68, P < 0.01), but not in girls (r = 0.27, P = 0.34). [Conclusion] Our results suggest that locomotive activity may be the main contributor to the individual PAL differences for elementary school boys, while non-locomotive activity may be the main contributor for elementary school girls.

Purpose The effect of BCAA (branched chain amino acid) administration on muscle atrophy during growth phases is not well known. We investigated whether BCAA administration can prevent the muscle atrophy induced by hindlimb suspension in growing male rats. Methods Male Wistar rats were assigned to 1 of 2 groups (n = 7/group): hindlimb suspension and hindlimb suspension with oral BCAA administration (600 mg·kg(-1)·day(-1), valine 1: leucine 2: isoleucine 1). After 14 days of hindlimb suspension, the weight and mRNA levels of the soleus muscle were measured. Results BCAA administration prevented a decrease in soleus muscle weight. BCAA administration attenuated atrogin-1 and MuRF1 mRNA expression, which has been reported to play a pivotal role in muscle atrophy. Conclusion BCAA could serve as an effective supplement for the prevention or treatment of muscle atrophy, especially atrophy caused by weightlessness.