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Purpose The purpose of this study was to evaluate the diagnostic performance of acoustic radiation force impulse (ARFI) elasticity imaging. Materials and Methods One hundred and twenty-seven thyroid nodules were examined by both ARFI elastography and B-mode sonography. Virtual Touch tissue quantification (VTQ) values of the thyroid nodules were measured. Scoring of B-mode sonographic findings of each thyroid nodules was performed. The sums of these VTQ and the B-mode scores were determined. The comparative diagnostic performances of the VTQ value, the B-mode score, and the combined score were analyzed. Results The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of each scoring mode were: B-mode score, 84%, 85%, 66%, 94%, and 85%; VTQ, 75%, 91%, 73%, 92%, and 86%; and combined score, 88%, 87%, 70%, 95%, and 88%. The areas under the curves for B-mode, VTQ, and combined score were 0.895, 0.837, and 0.912, respectively. Pairwise comparisons of receiver-operating characteristic curves showed no statistical differences between B-mode and VTQ, and B-mode and combined score. Combined score showed better diagnostic performance than VTQ value (p = 0.0023). Conclusion ARFI VTQ value is a good diagnostic modality for differentiating malignant thyroid nodules from benign nodules. However, ARFI evaluation is not superior to B-mode sonographic evaluation, but only has a better diagnostic performance when combined with B-mode sonographic findings.

Sleep architecture and sleep patterns normally change with aging. In preclinical Alzheimer’s disease (AD), the accumulation of amyloid plaques begins 10 to 20 years before any cognitive symptoms progress. Soluble amyloid-β (Aβ) is secreted during physiological synaptic activity. Since synaptic activity is correlated with sleep and awake state, a degree of Aβ fluctuates in a diurnal sleep pattern. In animal and human studies, a degree of sleep quality showed a significant correlation with brain levels of Aβ and a risk of AD. Conversely, Aβ aggregation would debilitate neuronal function in brain regions critical to sleep and wake promotion. This bidirectional relationship can be explained as positive feedback loop and associated factors that influence this relationship. In AD, the degree of sleep disturbances is much more severe compared with in the normal elderly. Further, Sundowning syndrome and a reduction of melatonin level cause a stressful neuropsychiatric symptoms and a disruption of physiological sleep rhythm, respectively. In AD patients, a correlation between sleep architectural modifications and learning performances has been reported. Moreover, executive function and emotional reactivity might be attenuated by sleep disturbances, too. However, sleep disturbance does not impact cognitive functions of all patients with AD. This could support an individual and potentially genetically determined susceptibility. Sleep disturbances have an important effect on patients and caregivers. It has a critical value to confirm and treat individuals with sleep disorders and to explore whether good quality of sleep in humans can decrease the progression of preclinical to symptomatic AD.

Background and Objective Although the sleep disturbances are very common and serious behavioral symptoms in Alzheimer’s disease (AD), the neuronal substrate of the gray matter structures associated with sleep disturbances in AD were not clear. The aim of this study is to investigate distinctive correlation patterns between the gray matter volume and sleep disturbances in AD. Methods Thirty drug-naïve patients with AD and 30 group-matched healthy control subjects underwent 3T magnetic resonance imaging scanning, and the whole brain gray matter volumes were measured using voxel based morphometry. We explored the correlation pattern between the gray matter volumes and the sleep disturbances in AD using the sleep disturbance subscale of Neuropsychiatric Inventory (NPI). Results Significant negative correlations were observed between left dorsolateral prefrontal cortex (DLPFC) and hypothalamus volumes and sleep disturbance subscale of NPI (false discovery rate corrected for multiple comparisons p < 0.05). Conclusions This study was the first to explore the relationships between whole brain gray matter volumes and sleep disturbances of drug-naïve patients with AD. These structural changes in DLPFC and hypothalamus might be the core of the underlying neurobiological mechanisms of sleep disturbances in AD.

Abstract Background Despite the well-known health benefits of exercise, women’s participation in exercise is low worldwide. As women are at risk of developing various chronic diseases as they age, suggesting effective exercise methods that can maximize energy consumption is needed to prevent such conditions. Excess post-exercise oxygen consumption (EPOC) can maximize energy consumption. In this crossover, randomized controlled trial, we aimed to compare the EPOC for different exercise modalities including continuous exercise (CE), interval exercise (IE), and accumulated exercise (AE) that spent the homogenized energy expenditure during exercise in healthy women. Methods Forty-four participants (age, 36.09 ± 11.73 years) were recruited and randomly allocated to three groups. The intensity of each modality was set as follows: CE was performed for 30 min at 60% peak oxygen uptake (VO2peak). IE was performed once for 2 min at 80% VO2peak, followed by 3 min at 80% VO2peak, and 1 min at 40% VO2peak, for a total of six times over 26 min. AE was performed for 10 min with a 60% VO2peak and was measured thrice a day. Results During exercise, energy metabolism was higher for IE and CE than that for AE. However, this was reversed for AE during EPOC. Consequently, the greatest energy metabolism was shown for AE during total time (exercise and EPOC). Conclusions By encouraging regular exercises, AE can help maintain and improve body composition by increasing compliance with exercise participation, given its short exercise times, and by efficiently increasing energy consumption through the accumulation of EPOC. Trial registration Clinical number (KCT0007298), 18/05/2022, Institutional Review Board of Konkuk University (7001355-202201-E-160).

Background: This study investigates the effects of a 12-week circuit exercise program on blood pressure, vascular function, and inflammatory cytokines in older obese women with sarcopenia. Methods: Twenty-eight older obese women with sarcopenia (mean age: 78.2 ± 3.7 years) were randomly divided into an exercise group (EG, n = 14) and a control group (CG, n = 14). The EG participated in a 12-week circuit exercise training regimen, conducted three times weekly, with each session lasting between 45 to 75 minutes (progressively increased over time). The CG was advised to maintain their regular daily routines throughout the intervention period. All dependent variables, including blood pressure, vascular function, and inflammation cytokines, were evaluated pre- and post-intervention. Results: Positive changes were observed in the EG in body composition (body fat mass; p < 0.001, body fat percentage; p < 0.01, free-fat mass; p < 0.01), blood pressure (heart rate; p < 0.05, rate pressure product; p < 0.01), vascular function (brachial–ankle pulse wave velocity; p < 0.05, flow-mediated dilation; p < 0.001), and inflammation cytokines (interleukin-6; p < 0.05). In the CG, there was an increase in body fat mass (p < 0.05) and body fat percentage (p < 0.05), while no changes were observed in other variables. Conclusions: The 12-week circuit exercise program significantly reduced blood pressure, improved vascular function, and decreased inflammatory cytokines in obese older women with sarcopenia. However, individual variations in response highlight the need for personalized exercise regimens.

Background: This study investigated the effects of 12-week resistance training on body composition, blood pressure, blood lipid levels, muscle cross-sectional area (CSA), isokinetic muscle function, and hemorheological properties in middle-aged obese women. Methods: Twenty-eight obese women with a mean age of 50.79 ± 5.80 years were randomly assigned to the control (CON, n = 13) or experimental (EXP, n = 15) group. The EXP group underwent a resistance training program composed of warm-up, main resistance exercise (deadlift, barbell squat, seated leg extension, and lying leg curl, bench press, preacher bench biceps curl, barbell rowing, and dumbbell shoulder press), and cool-down. The resistance exercise consisted of three sets of 8–10 repetitions (reps) performed with 70–80% of 1-rep maximum, and reps and sets were increased every 3 weeks. The training frequency was 80 min, 3 days per week for 12 weeks. The CON group maintained their daily lifestyle without training. All participants underwent measurements of body composition (weight, body mass index, lean body mass, fat mass, and % body fat), blood pressure (systolic blood pressure, diastolic blood pressure, mean arterial pressure, and pulse pressure), blood lipid levels (triglycerides, total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol), CSA of the muscles (quadriceps, hamstring, and total thigh muscle), isokinetic muscle function (peak torque [PT], relative PT, mean power, and total work [TW]), and hemorheological properties (erythrocyte deformability and aggregation) before and after 12 weeks of training. Results: The EXP group showed a significant improved muscle function, including PT (p < 0.001), relative PT (p < 0.001) in extension 60°/s, TW (p < 0.001) in extension 180°/s, and TW (p = 0.018) in flexion 180°/s. Regarding hemorheological properties, the EXP group showed significant improvement in erythrocyte aggregation (p < 0.001) and deformability (p < 0.001). Conclusions: The present study verified that our resistance training program resulted in greater muscle function, decreased fat mass, and improved hemorheological properties. Clinical Trial Registration: This study was registered with cris.nih.go.kr (No. KCT0007412).

This study aimed to compare vascular function, cardiometabolic parameters, hemorheological function, and cardiorespiratory fitness in middle-aged Korean women according to obesity defined using body mass index (BMI). A total of 32 Korean women aged between 34 and 60 years (16 without obesity, mean age 46.31 ± 7.49 years and 16 with obesity, mean age 49.68 ± 6.69 years) participated in this study. Obesity was defined as BMI ≥ 25 kg/m2. The body composition, vascular function, cardiometabolic parameters, hemorheological function, and cardiorespiratory fitness of all participants were measured. Statistical differences in the dependent parameters between individuals with and without obesity were analyzed, and the correlations between BMI and the dependent variables were verified. The obese group showed significantly worse results (p

The current study compared the effects of exercise program and a rehabilitation exercise program (REP) with electro muscle stimulation (EMS) on participants who had anterior cruciate ligament (ACL) reconstruction. The control group (CONG, n = 12) and the electro muscle stimulation group (EMSG, n = 12) were equally assigned among the 24 patients who underwent ACL reconstruction. For 12 weeks, CONG executed the REP, and EMSG executed of added EMS into the REP. Every participant in the rehabilitative exercise program completed two 60 min sessions each week for a total of 12 weeks. Both a pre- and post-evaluation were completed before and after the workout session. IKDC (International Knee Documentation Committee) score, Lysholm score, thigh circumference, muscular activity, and isokinetic muscle function were the variables examined. The EMSG exposed a significant increase (p < 0.05) in Lysholm score, muscle circumference, muscle activity of vastus medialis (VM), rectus femoris (RM), and vastus lateralis (VL), and isokinetic function (peak torque, total work). However, CONG only showed a significant increase in IKDC score (p < 0.05). This study proved that the REP employing EMS following ACL reconstruction enhanced muscular activation during muscle contraction when compared to REP, and it showed that using EMS in rehabilitation exercise is an effective rehabilitation strategy.

The purpose of the study was to examine the development of a multiple linear regression model to estimate heart rate variability (HRV) parameters using easy-to-measure independent variables in preliminary experiments. HRV parameters (time domain: SDNN, RMSSD, NN50, pNN50; frequency domain: TP, VLF, LF, HF) and the independent variables (e.g., sex, age, body height, body weight, BMI, HR, HR max , HRR) were measured in 75 healthy adults (male n = 27, female n = 48) for estimating HRV. The HRV estimation multiple linear regression model was developed using the backward elimination technique. The regression model’s coefficient of determination for the time domain variables was significantly high (SDNN = R 2 : 72.2%, adjusted R 2 : 69.8%, P < .001; RMSSD = R 2 : 93.1%, adjusted R 2 : 92.1%, P < .001; NN50 = R 2 : 78.0%, adjusted R 2 : 74.9%, P < .001; pNN50 = R 2 : 89.1%, adjusted R 2 : 87.4%, P < .001). The coefficient of determination of the regression model for the frequency domain variable was moderate (TP = R 2 : 75.6%, adjusted R 2 : 72.6%, P < .001; VLF = R 2 : 41.6%, adjusted R 2 : 40.3%, P < .001; LF = R 2 : 54.6%, adjusted R 2 : 49.2%, P < .001; HF = R 2 : 67.5%, adjusted R 2 : 63.4%, P < .001). The coefficient of determination of time domain variables in the developed multiple regression models was shown to be very high (adjusted R 2 : 69.8%–92.1%, P < .001), but the coefficient of determination of frequency domain variables was moderate (adjusted R 2 : 40.3%–72.6%, P < .001). In addition to the equipment used for measuring HRV in clinical trials, this study confirmed that simple physiological variables could predict HRV.

The present study examined the effects of a rehabilitation exercise program with blood flow restriction (BFR) vs. a general rehabilitation exercise program in patients who have undergone anterior cruciate ligament (ACL) reconstruction. Among a total of 24 patients, the general rehabilitation exercise group (GRE, n = 12) and blood flow restriction group (BFR, n = 12) were assigned the same. The GRE group conducted a general rehabilitation exercise, and the BFR group conducted a BFR exercise along with the general rehabilitation exercise. All participants performed the rehabilitation exercise program session for 60 min three times a week for 12 weeks under supervision. All dependent parameters (Lysholm score and International Knee Documentation Committee (IKDC) subjective score, muscle activity, isokinetic muscular function, Y-balance test) were evaluated before and after the rehabilitation exercise program. GRE improved the Lysholm score, IKDC subjective score and Y balance test (posterior-medial, posterior-lateral) (p < 0.05). Moreover, BFR was effective in improving the Lysholm score and IKDC subjective score and muscle activity (e.g., vastus medialis oblique during isokinetic contraction and rectus femoris during isometric contraction), isokinetic function (e.g., peak torque and total work) and Y-balance test (e.g., anterior, posterior medial, posterior lateral) (p < 0.05). Our study confirmed that a rehabilitation exercise program with BFR after ACL reconstruction is a more effective rehabilitation modality for improving muscle activity during muscle contraction and muscle function compared with GRE. Therefore, it is recommended to use BFR as an effective rehabilitation program for rapid recovery after ACL reconstruction.

This study aimed to investigate the effects of acute moderate hypoxia (HYP), compared with those of normoxia (NORM), during endurance exercise with the same HR level on metabolic function, skeletal muscle oxygenation, and cardiac function. Twelve healthy men (aged 25.1 ± 2.3 years) completed 30 min of endurance exercise using a cycle ergometer with the same HR level (136.5 ± 1.5 bpm) corresponding to 70% maximal heart rate (HRmax) under NORM (760 mmHg) and HYP (526 mmHg, simulated 3000 m altitude) after a 30 min exposure in the respective environments on different days, in random order. Exercise load, rating of perceived exertion (RPE), metabolic function (saturation of percutaneous oxygen; SpO2, minute ventilation; oxygen uptake; VO2, carbon dioxide excretion; respiratory exchange ratio; RER, and oxygen pulse), skeletal muscle oxygen profiles (oxyhemoglobin, oxhb, deoxyhemoglobin, dxhb, total hemoglobin, and tissue oxygenation index; StO2), and cardiac function (heart rate, stroke volume, cardiac output, end-diastolic volume, end-systolic volume, and ejection fraction) were measured during endurance exercise. HYP showed a lower exercise load with the same RPE during exercise than did NORM. In addition, HYP showed a lower SpO2, VO2, oxygen pulse, oxhb, and StO2, and a higher RER and dxhb during exercise than NORM. We found that HYP showed lower exercise load and VO2 at the same RPE than NORM and also confirmed a higher anaerobic metabolism and oxygen inflow into skeletal muscle tissue due to the limitation of oxygen delivery capacity.

This study aimed to analyze the status of sarcopenia, obesity, osteoporosis, and cardiometabolic disease according to the level of physical activity (PA) among elderly people in Korea. Among the data obtained from the National Health and Nutrition Survey (2008–2011), we analyzed the data of a total of 3,573 Korean elderly people over 65 years of age who were surveyed for dual X-ray absorptiometry (DXA) and PA. Higher levels of PA were associated with a lower prevalence of cardiometabolic disease (χ2 = 33.865, p < 0.001), osteoporosis (χ2 = 94.198, p < 0.001), sarcopenia, obesity, and sarcopenic obesity (χ2 = 71.828, p < 0.001). Above moderate-active PA was associated with lower body weight (p < 0.001), body fat mass (p < 0.001), and percent body fat (p < 0.001), and higher free-fat mass (p < 0.001) and appendicular skeletal muscle mass (ASM) (p < 0.001) than in low-active PA. In addition, when high-active is the risk factors of cardiometabolic were lower in waist circumference (p = 0.001), total cholesterol (TC) (p = 0.015), and triglyceride (TG) (p < 0.001) than low- and moderate-active PA, and higher in high-density lipoprotein cholesterol (HDL-C) (p < 0.001). The prevalence of cardiometabolic diseases was significantly decreased in high-active PA (odds ratio (OR) 0.60, 95% confidence interval (CI) 0.50–0.71); waist circumference (OR 0.85, 95% CI, 0.73–0.99; OR 0.59, 95% CI, 0.50–0.70) and HDL-C (OR 0.76, 95% CI, 0.65–0.88; OR 0.56, 95% CI, 0.47–0.67) significantly improved in moderate- and high-active PA, respectively, and TG (0.67 95% CI, 0.55–0.80) significantly improved in high-active PA. Osteoporosis (OR 0.62, 95% CI, 0.53–0.74; OR 0.46, 95% CI, 0.38–0.55) and sarcopenia (OR 0.77, 95% CI, 0.60–0.98; OR 0.73, 95% CI, 0.57–0.93) were significantly improved in moderate- and high-active PA, respectively. The incidence of obesity (OR 0.47, 95% CI, 0.39–0.57) and sarcopenic obesity (OR 0.47, 95% CI, 0.30–0.75) were significantly decreased in high-active PA. Therefore, we verified a lower prevalence of sarcopenia, osteoporosis, obesity, and cardiac metabolic disease in Korean elderly with more active PA. This suggests that more active PA maybe reduce the prevalence of sarcopenia, osteoporosis, obesity, and cardiometabolic diseases in older adults.

Cardiovascular diseases (CVDs) are recognized as one of the major causes of morbidity and mortality worldwide. Generally, most CVDs can be prevented by addressing behavioral risk factors, including smoking, unhealthy diet and obesity, lack of physical activity, and alcohol abuse. Therefore, it is important to have a healthy lifestyle by performing regular physical activity to improve cardiovascular health and diseases. However, a majority of adults worldwide do not meet the minimum recommendations for regular aerobic exercise, and overweight and obesity ratio continues to rise. In addition, obese individuals, with a high prevalence of CVDs, have a lower participation rate for exercise because of the strain on the musculoskeletal system. Hypoxic therapy, including exposure or exercise intervention under hypoxia, has been utilized as a new therapeutic modality for cardiovascular benefit and amelioration of CVDs. Hypoxic therapy shows various physiological and pathophysiological properties, including increased appetite suppression and dietary intake reduction, increased energy consumption, improved glycogen storage, enhanced fatty acid oxidation, improved myocardial angiogenesis or ventricular remodeling, augmentation of blood flow within the skeletal muscle vascular beds, and reduction of the burden on the musculoskeletal system making it applicable to patients with CVDs and obesity with attenuated cardiovascular function. In particular, hypoxic therapy is very effective in improving cardiovascular benefits and preventing CVDs by enhancing arterial function, vascular endothelial function, and hemorheological properties. These observations indicate that hypoxic therapy may be an important and essential strategy for improving cardiovascular health and reducing cardiovascular morbidity and mortality.

Background: Sarcopenic obesity is caused by a decrease in muscle mass and an increase in body fat due to aging, and has been the cause of cardiovascular diseases such as hypertension, diabetes, hyperlipidemia, and arteriosclerosis and high inflammatory conditions. However, there is a lack of research on the effects of long-term exercise training as regards to the body composition and blood-related physiological indicators. Therefore, the purpose of this study was to investigate the influences the effect of circuit exercise training for 12 weeks on cardiovascular risk factors, vascular inflammatory markers, and insulin-like growth factor-1 (IGF-1) in elderly obesity women with sarcopenia. Methods: A total of 28 elderly obese Korean women with sarcopenia (75.0 ± 5.1 years) were randomly assigned either to a control group (CG, n = 14) or an exercise group (EG, n = 14). The EG performed circuit exercise training for 25–75 minutes (gradually incremental) three times per week over a period of 12 weeks, while the CG maintained their usual daily lifestyle during the intervention period. Pre- and post-intervention evaluations were performed on selected cardiovascular risk factors, inflammatory markers, and IGF-1. Results: The EG group exhibited improved body composition (i.e., body mass index, fat-free mass, % fat mass, waist-to-hip ratio; all p < 0.030, η2 > 0.169), Cardiovascular risks factor (i.e., heart rate, systolic blood pressure, rate pressure product, high-density lipoprotein cholesterol, total cholesterol/HDL-C ratio, triglyceride/HDL-C ratio, low-density lipoprotein cholesterol/HDL-C ratio, brachial-ankle pulse wave velocity, fasting plasma insulin, homeostasis model assessment-insulin resistance; all p < 0.042, η2 > 0.150), Inflammatory markers (i.e., high sensitivity C-reactive protein, interleukin-6; all p < 0.045, η2 > 0.146), and IGF-1 (p = 0.037, η2 = 0.157). Conversely, there were no significant changes observed in CG. Conclusions: Twelve weeks of circuit training had a positive effect on the improvement in cardiovascular risk factors, vascular inflammatory markers, and IGF-1 in elderly obese women with sarcopenia.

Background: This study aimed to compare and analysis of cardiopulmonary function, energy metabolism, and exercise intensity and time according to the number of repetitions of Taekwondo Taegeuk Poomsae in Taekwondo players. Methods: The participants were 29 healthy men (19.5 ± 1.2) who could perform Taekwondo Taeguek Poomsae 1 to 8 Jang. Results: Minute ventilation, oxygen consumption, and carbon dioxide excretion, which assess cardiopulmonary function, were highest in 1st repetition of Taegeuk 6–8 Jang and 5th and 10th repetitions of Taegeuk 4 and 5 Jang, respectively. The respiratory exchange ratio was highest in 1st repetition of Taegeuk 1 Jang and 5th and 10th repetitions of Taegeuk 8 Jang. Regardless of the number of repetitions, carbohydrate oxidation was highest in Taegeuk 8 Jang, and energy consumption was highest in Taegeuk 5–8 Jang. The amount of fat oxidation was higher in 1st repetition of other Taegeuk Poomsaes than in 1st repetition of Taegeuk 1 and 2, and a similar occurrence was observed with 5th repetitions. However, at the 10th repetition, Taegeuk 8 Jang was the lowest. Regarding exercise intensity and time, the percentage heart rate maximum exercise intensity for 1st repetition of the Poomsaes was 54%–63%, for 5th repetitions was 69%–82%, and for 10th repetitions was 72%–87%. The time duration according to the number of repetitions was 0.31 to 0.66 minutes for 1st repetition, 2.05 to 3.79 minutes for 5th repetitions, and 4.22 to 7.70 minutes for 10th repetitions. Conclusions: This study suggests that as the number of repetitions of Taekwondo Taegeuk Poomsae increased, the cardiopulmonary function, exercise intensity, and energy metabolism increased. In particular, cardiopulmonary function and exercise intensity were similar for all but Taegeuk Poomsae 1 Jang, but the energy consumption was higher in Taegeuk 5–8 Jang than in Taegeuk 1–4 Jang.

Background: Obesity is recognized as an important global health problem that increases the risk of all-cause death. It is a major risk factor for various cardiovascular and metabolic diseases. Methods: We conducted this review through searching the related literature plus internet links. Results: Recently, many researchers have been applying various efficient alternative exercise paradigms for treating obesity, such as high-intensity interval training, whole-body vibration training, and hypoxic therapy. Compared with moderate-intensity continuous training, high-intensity interval training involves a shorter exercise time but higher energy expenditure and excess post-exercise oxygen consumption via a higher exercise intensity and is effective for treating obesity. Whole-body vibration training effectively reduces the rate of fat production and accumulation through passive vibration of the whole body and improving the body composition, muscle function, and cardiovascular function of the obese population. Hypoxic therapy has been reported to improve obesity and obesity-related diseases through appetite loss, reduced dietary intake, increased energy consumption, improved glycogen storage and fatty acid oxidation, angiogenesis and left ventricle remodeling, decreased mechanical load, and reduced sarcopenia progression due to aging. Conclusion: The new therapeutic exercise modalities, namely, high-intensity interval training, whole-body vibration training, and hypoxic therapy, are practical, useful, and effective for improving obesity and various metabolic and cardiovascular diseases induced by obesity.

Hypoxic training is believed to be generally useful for improving exercise performance in various athletes. Nowadays, exercise intervention in hypoxia is recognized as a new therapeutic modality for health promotion and disease prevention or treatment based on the lower mortality and prevalence of people living in high-altitude environments than those living in low-altitude environments. Recently, resistance training in hypoxia (RTH), a new therapeutic modality combining hypoxia and resistance exercise, has been attempted to improve muscle hypertrophy and muscle function. RTH is known to induce greater muscle size, lean mass, increased muscle strength and endurance, bodily function, and angiogenesis of skeletal muscles than traditional resistance exercise. Therefore, we examined previous studies to understand the clinical and physiological aspects of sarcopenia and RTH for muscular function and hypertrophy. However, few investigations have examined the combined effects of hypoxic stress and resistance exercise, and as such, it is difficult to make recommendations for implementing universal RTH programs for sarcopenia based on current understanding. It should also be acknowledged that a number of mechanisms proposed to facilitate the augmented response to RTH remain poorly understood, particularly the role of metabolic, hormonal, and intracellular signaling pathways. Further RTH intervention studies considering various exercise parameters (e.g., load, recovery time between sets, hypoxic dose, and intervention period) are strongly recommended to reinforce knowledge about the adaptational processes and the effects of this type of resistance training for sarcopenia in older people.

Interval training under hypoxia (IHT) is commonly used to enhance endurance exercise performance. However, previous studies examining hematologic changes related to the immune system that affect health and conditioning are lacking. This study aimed to evaluate the effects of IHT for 6-weeks on hematological parameters, hemodynamic function, and endurance exercise performance in amateur Korean female runners. Twenty healthy amateur Korean female runners (age: 24.85 ± 3.84 years) were equally assigned to normoxic training group (NTG) for interval training under normoxia (760 mmHg) and hypoxic training group (HTG) for interval training under hypobaric hypoxia (526 mmHg, 3000 m simulated altitude) according to their body composition and endurance exercise performance. All participants performed 120-min of training sessions, consisting of 20-min of warm-up, 60-min of interval training, and 20-min of cool-down. The training program was performed 3-days per week for 6-weeks. Warm-up and cool-down were performed for 20-min at 60% maximal heart rate (HRmax). The interval training sessions comprised 10 repetitions of interval exercise (5-min of exercise corresponding to 90–95% HRmax and 1-min of rest) on a treadmill. All participants underwent measurements of hematological parameters, hemodynamic function, and endurance exercise performance before and after training. Both groups showed a significant increase in erythropoietin (EPO) level and a decrease in monocyte abundance, with EPO showing a greater increase in the HTG than in the NTG. B cell abundance significantly increased in the NTG; hematocrit and neutrophil counts significantly increased, and lymphocyte counts significantly decreased in the HTG. The HTG showed a significant improvement in oxygen uptake, stroke volume index, and end-diastolic volume index compared to the NTG. In addition, both groups showed significant improvements in heart rate, end-systolic volume index, and cardiac output index. The maximal oxygen uptake and 3000 m time trial record were significantly improved in both groups, and the HTG showed a tendency to improve more than the NTG. In conclusion, the IHT was effective in enhancing endurance exercise performance through improved hemodynamic function. Furthermore, hematological parameters of immune system showed a normal range before and after training and were not negatively affected.

Purpose This study aimed to investigate the effects of acute cold stress (10℃, 0℃) compared with ordinary temperature (20℃) on exercise performance and physiological response at rest and during exercise. Methods A total of 10 healthy men (21.55 ± 2.16) were selected. In each environmental condition (20℃, 10℃, 0℃), the three testing order was randomly selected at crossover, and there was a week interval between the graded exercise test (GXT). On the testing day, they remained resting for 30 min in each environmental condition. Dependent variables (body temperature, energy metabolism parameters, skeletal muscle oxygenation profiles, and exercise performance parameters) were measured at rest and during GXT. Results In body temperature, at each environmental condition, there was a significant decrease (p

Background : : The present study examined the effects of a prolonged exercise intervention at the lactate threshold (LT) on body composition, aerobic performance, and the autonomic nervous system (ANS) in women with obesity. Methods : : A total of 36 obese Korean women aged 36 to 55 years (mean±standard deviation, 44.8±5.2 years) were randomly assigned to a control group (CON, n=18) or an experimental group (EXP, n=18); and EXP underwent aerobic exercise training three times a week at a heart rate corresponding to the LT (HR_LT) for 12 weeks. All dependent variables (body composition, aerobic performance, and ANS function parameters) were evaluated before and after training. Results : : Compared with the CON group, the EXP group showed significant improvement in body composition (body weight, −4.57 vs. −2.40 kg; body mass index, −1.79 vs. −0.96 kg/m2; %body fat, −4.63 vs. −1.41; fat-free mass, 3.24 vs. –0.08 kg), aerobic performance (oxygen consumption at LT, 5.74 vs. 0.12 mL/kg/min; maximal oxygen consumption, 5.41 vs. 2.14 mL/kg/min; treadmill speed at HR_LT, 1.40 vs. 0.29 km/hr; bicycle load at HR_LT, 18.62 vs. 4.52 w; and ANS function (mean RR, 50.83 vs. −15.04 ms; standard deviation of NN intervals, 5.08 vs. −0.55 ms; root mean square of successive differences, 6.42 vs. 1.87 ms; total power, 0.34 vs. 0.10 ms2; high frequency, 0.32 vs. −0.04 ms2; low frequency/high frequency, −0.09 vs. 0.01). Conclusion : : Aerobic exercise at the LT for 12 weeks is a practical method of improving body composition, aerobic performance, and ANS function for women with obesity.

The aim of this study was to investigate the microstructural alterations of white matter (WM) in Alzheimer's disease (AD) patients with apathy and to observe the relationships with the severity of apathy. Sixty drug-naïve subjects took part in this study (30 apathetic and 30 nonapathetic subjects with AD). The loss of integrity in WM was compared in AD patients with and without apathy through measurement of fractional anisotropy (FA) using by tract-based spatial statistics (TBSS). In addition, we explored the correlation pattern between FA values and the severity of apathy in AD patients with apathy. The apathy group had significantly reduced FA values (p(corrected)