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A decline in estrogen levels during menopause is associated with the loss of muscle mass and function, and it can accelerate sarcopenia. However, with the growing number of postmenopausal women due to the increase in life expectancy, the effects of estrogen on skeletal mus-cle are not completely understood. This article reviews the relationship between estrogen deficiency and skeletal muscle, its potential mecha-nisms, including those involving mitochondria, and the effects of exer-cise on estrogen deficiency-induced skeletal muscle impairment. In particular, mitochondrial dysfunction induced by estrogen deficiency accelerates sarcopenia via mitochondrial dynamics, mitophagy, and mitochondrial-mediated apoptosis. It is well known that exercise train-ing is essential for health, including for the improvement of sarcopenia. This review highlights the importance of exercise training (aerobic and resistance exercise) as a therapeutic intervention against estrogen de-ficiency-induced sarcopenia.

Chronic pain is defined as pain that persists past the normal healing time. Physical activity and exercise programs are increasingly being promoted and used for a variety of chronic pain conditions. Evidence suggests that physical exercise is an intervention with few adverse events that may improve pain severity and physical function, thus im-proving the quality of life. High-intensity interval training (HIIT) has been shown to improve physical outcome measures and to decrease disor-der-related disability in people with chronic disorders. Since an over-view of the benefits of HIIT on chronic pain conditions has not been published yet, this review aims to report the effects of HIIT alone or in combination with other forms of training on different kind of chronic pain conditions. A search in the main scientific electronic databases was performed. The results of the studies included in this review showed that HIIT is beneficial for several chronic pain conditions, im-proving pain and physical function. Since HIIT could represent a valid help to conventional drug therapies, it could improve the quality of life of these subjects. The actual quality of evidence remains very low, and further high evidence studies are needed to confirm the promising out-comes reported in this review.

We examined whether exercise is associated with hippocampus-medi-ated improvement in insulin signaling and cell differentiation in the triple transgenic mouse model of Alzheimer disease (3xTg AD) murine model following exposure to 40-Hz light flickering and exercise. We subjected 12-month-old 3xTg AD mice to exercise and 40-Hz light flickering for 3 months. The exercise session was proceeded for 12 consecutive weeks with gradual increase of intensity. To investigate insulin signaling proteins, western blot was conducted to detect the ratio of phosphory-lated insulin receptor β (p-IRβ)/total IRβ (t-IRβ), phosphorylated insulin receptor substrate 1 (p-IRS-1)/total IRS-1 (t-IRS-1), phosphorylated phosphatidylinositide-3-kinase (p-PI3K)/total PI3K (t-PI3K), phosphory-lated 3-phosphoinositide dependent protein kinase-1 (p-PDK1)/total PDK-1 (t-PDK1), phosphorylated protein kinase B (p-Akt)/total-Akt (t-Akt), and phosphorylated glycogen synthase kinase 3 beta (p-GSK3β)/total GSK3β (t-GSK3β). Doublecortin immunohistochemistry was per-formed for assessing cell differentiation in the hippocampus. Treatments exerted a positive effect. The combination of exercise and 40-Hz light flickering exposure was the most effective treatment enhancing insulin signaling. Increased ratio of p-IRβ/t-IRβ, p-IRS-1/t-IRS-1, p-PI3K/t-PI3K, p-PDK1/t-PDK1, p-Akt/t-Akt, and p-GSK3β/t-GSK3β and enhanced cell differentiation were observed in the 3xTg AD with exercise under 40-Hz light flickering group. Our results indicate that exercise under 40-Hz light flickering most potently improved insulin signaling, thereby promoted cell differentiation.

We reported that application of ethanol with lipopolysaccharide (LPS) and carbon tetrachloride (CCl4) enhanced alanine aminotransferase (ALT) and aspartate aminotransferase (AST) level. In the current experi-ment, the protective effect of treadmill running on liver injury caused by ethanol with LPS and CCl4 in mice was studied. Liver injury severity was determined by measuring ALT and AST level in the blood. Terminal de-oxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining, immunohistochemistry for caspase-3, and Western blotting for Bcl-2-associated X protein (Bax) and B-cell lymphoma 2 (Bcl-2) were performed to indicate hepatocyte apoptosis. In addition, to understand the mechanism, 5’-adenosine monophosphate-activated protein kinase (AMPK) phosphorylation was studied by Western blotting. Treadmill ex-ercise ameliorated ethanol with LPS and CCl4-mediated elevation of ALT and AST level. Treadmill exercise suppressed ethanol with LPS and CCl4-mediated elevation of the TUNEL-positive cell number and cleaved caspase-3 expression. Treadmill exercise suppressed ethanol with LPS and CCl4-mediated elevation of Bax expression and increased Bcl-2 ex-pression suppressed by application of ethanol with LPS and CCl4. Tread-mill exercise enhanced AMPK phosphorylation which was suppressed by application of ethanol with LPS and CCl4. Treadmill exercise has the effect of reducing liver damage caused by alcohol and or drug addiction.

This study examined the association among cognitive function, physical fitness, and health status in healthy older women. Ninety-four females aged from 62 to 86 years (72.66±5.38 years) from community healthcare centers and an exercise club in Seoul, South Korea. Cognitive function was assessed using the Seoul Neuropsychological Screening Battery. Physical performance comprised cardiorespiratory endurance, lower extremity strength, active balance ability, and walking speed. Health status included blood pressure and waist circumference. Multiple lin-ear regression analyses were performed to determine the relationship among cognitive function, fitness components, and health status, with age and educational attainment as covariates. In the unadjusted model, attention was significantly associated with cardiovascular endurance (B=0.19, P<0.05). Memory was significantly associated with lower limb strength (B=0.77, P<0.05) and active balance ability (B=2.35, P<0.05). In the adjusted model, attention was significantly associated with car-diovascular endurance (B=0.15, P<0.05). Memory was significantly as-sociated with lower limb strength (B=0.87, P<0.05). In both models, cognitive function was not significantly associated with any health sta-tus variable. Though limited by a relatively small sample of female par-ticipants, who were healthy registrants of a community exercise pro-gram with normal cognitive function, the current study demonstrates that cognitive function is significantly associated with physical fitness, but not with health status, in healthy older women.

The purpose of this study was to investigate the effects of a 4-week moderate-intensity aerobic exercise on changes of body composition and markers of inflammation and oxidative stress independent from weight loss in middle-aged obese females. Thity-five obese females were randomly assigned to either an exercise (EX, N=16) or control (CON, N=19) group. The EX performed moderate intensity aerobic ex-ercise on the treadmill for 60 min at 55% of maximal oxygen consump-tion (VO2max) for 4 weeks (3 days/wk). Body composition measurement with dual-energy x-ray absorptiometry and blood collection were con-ducted before and after the 4-weeks intervention. Blood samples were used to measure levels of tumor necrosis factor-alpha (TNF-α), C-reac-tive protein, adiponectin, total antioxidant status (TAS), and 8-hy-droxydeoxyguanosine. Four weeks of aerobic exercise intervention sig-nificantly increased VO2max in EX (P<0.001). EX also observed a decrease in TNF-α (P=0.033) and an increase in TAS (P=0.028) without changes in body weight and fat mass after 4 weeks of aerobic exercise training. No changes were observed in CON after the intervention. Results of this study indicate that moderate aerobic exercises may contribute, at least a part, to reductions of inflammation and oxidative stress inde-pendently from fat loss. Therefore, it may reduce risks of obesity-asso-ciated disorders in middle-aged obese females.

This study was conducted to investigate the effect of regular endur-ance exercises on the management of cardiovascular health in mid-dle-aged men. The following conclusions were drawn as the result of comparatively analyzing middle-aged men who regularly performed tri-athlon and cycling exercises for more than 5 years. The effect of regular endurance exercises on cardiovascular health management in middle- aged men was found to be relatively positive. However, prolonged en-durance exercises can cause cardiovascular disease which can ad-versely affect the cardiac function, and to date, no defining limit is known about the amount of exercise that improves the cardiovascular function while reducing the cardiovascular events. Therefore, aiming for exer-cises at moderate intensity that befit the individual’s fitness level as well as conducting regular examinations to predict and manage the risk of sudden cardiac death from exercising were considered as the more ef-fective method of cardiovascular health management.

A randomized crossover trial was carried out in prehypertensive obese men to compare postexercise hypotension and heart rate variability (HRV) following water-based and land-based high-intensity interval exercises (HIIEs). Nine prehypertensive obese participants, aged 23.6± 2.4 years, were randomly assigned to one of three interventions: no-ex-ercise control, HIIE with immersion up to the chest, or HIIE on dry land. In the evenings of three separate days, participants performed either of the interventions. Matched with exercise volume, both HIIEs com-posed of 5 repetitions of 30-sec sprints at maximum effort followed by a 4-min rest. Ambulatory blood pressure and HRV were measured before the interventions and over the 24-hr following period. Both HIIEs result-ed in significant reductions of average 24-hr mean arterial pressure (-6.7 mmHg). Notably, the water-based HIIE resulted in a significantly higher reduction of 24-hr systolic blood pressure (SBP) (-9 mmHg) than the land-based HIIE, particularly at night, in addition to a significantly longer duration of postexercise hypotension. Finally, the water-based HIIE was more effective at restoring HRV during recovery. Our findings demonstrated postexercise hypotension following the HIIEs, particular-ly the water-based HIIE. During recovery, the water-based HIIE was re-markably effective at restoring HRV. These findings indicate that water- based HIIE is more effective at reducing SBP and requires less recov-ery time than land-based HIIE in prehypertensive obese men.

The purpose of this study was to analyze the characteristics of injuries in female national soccer players. The injuries data were recorded by Korea Football Association medical staff using the Daily Medical Report provided by the Asian Football Confederation during a total 21 training camps and friendly and official matches from January 2014 to Decem-ber 2018. A total of 483 players in the national team training camps and matches participated in the study, of which 377 players experienced more than one injury. Sports injuries accounted for 89% of the total 1,019 injuries; general diseases accounted for the remaining 11%. The num-ber of injuries per 1,000 exposure hours was higher in matches than in training sessions. Most injuries that occurred during training and matches involved the lower extremities (79%). The most common injury diagnosed during training and matches was muscle rigidity (45%), fol-lowed by contusions/hematomas/bruises (22%) and sprain (15%). The largest proportions of injuries in terms of absence from soccer play were minimal injury (67%), followed by mild (29%), moderate (3.5%), and severe (1%). As conclusion, the characteristics of injuries during train-ing sessions and matches were different. Rehabilitation and injury pre-vention programs need to developed for female soccer players to im-prove the players’ performance.

Service-learning (SL) has been implemented widely in teacher educa-tion to connect knowledge and practical experiences. In the field of Physical Education Teacher Education, Adapted Physical Education (APE) Courses have been implemented SL to provide hands-on experi-ences to promote preservice teachers’ attitudes toward individuals with disabilities. The purpose of this study is to investigate the effective-ness of two SL projects, the volunteer project, and the parasports proj-ect, in the Intro APE course on preservice teachers’ attitudes toward individuals with disabilities. A total of 130 preservice teachers partici-pated in this study taking the Multidimensional Attitude Scale Toward Persons with Disabilities (MAS) before and after completing two SL projects. The result of the t-test indicated that there is no difference in overall MAS scores between pre- and posttest (Meanpre=2.954, SDpre=0.689, Meanpost=3.01, SDpost=0.679; t(129)=0.390, P=0.784). However, the significant increase observed in affects subscale of MAS (Meanpre=3.47, SDpre=0.374, Meanpost=3.52, SDpost=0.188; t(129)= 0.347, P=0.327). Our finding indicated cognition and behavior of preser-vice teachers toward individuals with disabilities were positively in-creased, but not significantly improved yet. Evidence suggested that two SL projects in this study did not significantly improve the overall positive attitudes of preservice teachers toward individuals with disabil-ities, but it was meaningful to observe that preservice teachers increased their affects toward individuals with disabilities.