Objective: We aimed to establish a novel approach that enables the prediction of behavioral effects of lesions using neuroimaging data, which is applicable to sportological analyses, particularly in identifying the links between brain activity and behavior related to sports.

Materials and Methods: Experimental details are described in our previous reports (Miyamoto et al., 2013; Osada et al., 2015). Four monkeys (M. mulatta and M. fuscata) were used. All experimental protocols, animal welfare, and steps for minimizing suffering were in full compliance with the Guidelines for Proper Conduct of Animal Experiments by Science Council of Japan.

Functional images were acquired using a 4.7-T MRI scanner (Biospec47/40, Bruker) during a recognition or temporal-order judgment task. Monkeys performed the tasks while sitting in an MRI-compatible chair. Group analyses of image data were conducted using SPM5.

Results: A task-evoked connectivity network was identified based on data from the functional imaging conducted during recognition tasks (Miyamoto et al., 2013) and temporal-order judgment tasks (Osada et al., 2015). A significant positive correlation was observed between the predicted impact on performance and the betweenness centrality based on task-evoked connectivity network, whereas no correlation was observed between the predicted impact on performance and the betweenness centrality based on anatomical connectivity network.

Conclusions: Severity of impairment arising from local brain damage was predicted by network “hubness” of the damaged area in the task-evoked connectivity network. These findings will form the basis for future research that aims to predict the functional brain center for watching or partaking in sports.

Participation in sports by children in the United States over the past 3 decades has seen a move from spontaneous and fun activity by children and adolescents to a more organized and competitive activity largely governed by adults and sports governing organizations. With this shift we have also seen a trend in participation in organized sports at younger age, increase in intensity in activity level, and specialization in a single sport from an early age. These and other factors contribute to an increased incidence of sport related overuse injuries in children and adolescents. Another area of intense debate and scrutiny is the long term neurocognitive impact in adolescents of sport-related concussions. Recognition of adverse long term impact of sport related concussions on developing brain has resulted in increased education efforts, prevention strategies, and legislative activity. Screening of young athletes for cardiovascular disease to prevent sudden cardiac death also continues to be a subject of ongoing intense debate in the United States.

In order to establish healthy society as legacy of 2020 Games, the Sportology must be promoted and implement concrete actions.

A number of familial and twin studies have assessed the relative contribution of genetic and environmental factors to physical performance or its-related traits, and a significant genetic component has been predicted to affect phenotypes. A twin study indicated that the heritability of athletic status is 66%. Thus, genetic factors appear to be important for determining elite sporting performance. To date, over 200 genes in both nuclear DNA and mitochondrial DNA (mtDNA) have been reported to be associated with physical performance and health-related fitness. However, most studies have been reported in European populations. In the Asian population, only 3 genetic loci have been linked to physical performance, including angiotensin I-converting enzyme and α-actinin-3 genetic polymorphisms and mtDNA polymorphisms (mitochondrial haplogroups). In this review, we discuss the genetics of elite sporting performance, particularly in Asian populations, and their effects on lifestyle-related diseases such as type 2 diabetes and age-related muscle wasting (i.e., sarcopenia).

The prevalence of coronary artery disease (CAD) has increased over the last several decades in Japanese population. Recent epidemiological studies have indicated that the incidence of acute myocardial infarction (MI) has increased, particularly in the urban areas of Japan. Previous data have strongly supported the important role of lifestyle intervention, including physical activity and dietary modification to improve glucose and insulin homeostasis, lipid profiles, and other risk factors for the prevention of CAD. Cardiac rehabilitation (CR) is a comprehensive intervention that includes supervised exercise training, risk factor control, patient education, and psychosocial counseling. CR has been reported to be effective in reducing the risk of cardiovascular events through intensive lifestyle modification. However, the implementation of CR is still low even in academic cardiovascular institutes. In this review, we will discuss the recent status and problems regarding the safety and efficacy of CR and will discuss the future directions of CR in patients with CAD in Japan.

Obesity and its associated metabolic disorders are rapidly disseminating all over the world. While they became serious health problem, such diseases in Asians shows different features from those in other races such as Caucasian and African. One of the important features is a susceptibility to develop to type 2 diabetes even without excess body mass index. To search for the mechanism underlying this feature is important to find the suitable therapeutic strategy for Asian obesity. Thus, as a core study of the Sportology Center of Juntendo University Graduate School of Medicine, we assessed tissue-specific insulin resistance in Japanese non-obese subjects. In this study, we recruited non-obese and non-diabetic Japanese subjects and measured insulin sensitivity in muscle and liver by a 2-step hyperinsulinemiceuglycemic clamp with glucose tracer and ectopic fat content in muscle and liver by proton magnetic resonance spectroscopy. So far, our data suggests that muscle insulin resistance may play a central role in future onset of the diseases that could make the healthy people to disable people.

“Locomotive syndrome” is defined as a condition associated with being restricted in one’s ability to walk or lead a normal life owing to a dysfunction in one or more of the parts of the locomotion system, including the muscles, bones, joints, cartilage or the intervertebral discs. This syndrome especially refers to those elderly who have come to need nursing care services because of problems with the locomotive organs, or who have conditions which may require them to have such services in the near future. The recent epidemiological studies revealed that the one fourth of the reasons for requiring special assistance or nursing care in elderlies is currently the locomotive disorders. Osteoarthritis of the knee (knee OA) or hip and the spinal canal stenosis due to spondylosis are the three major locomotive disorders those are related to the requiring special assistance or nursing care in elderlies. We are trying to elucidate the mechanistic insight into the pathophysiology of knee OA and osteoporosis by receiving several supports, such as the COI program by a MEXT and the Juntendo Sportology Center under the concept of “Sportology”, as we believe to be able to contribute directly the concept of “locomotive syndrome” by these actions.

Mechanical stresses play various different roles in regulating organismal functions, depending on the situation when and where they are borne. Cell signaling related to ‘straining’ mechanical stresses, such as cell stretching, pressurizing, cytoskeletal tensioning, adhesion to stiff substrate, and high traction force generation, is imperative in the ‘constructive’ phase of tissues and organs, including development, regeneration and repair. However, once steady state is reached upon completion of tissue/organ formation, straining mechanical stress often causes failure of organismal homeostasis, such as inflammation and cancer. In contrast to such ‘detrimental’ aspect of straining stress, relaxing mechanical stress contributes to maintenance of homeostasis. Collectively, balance and integration between straining and relaxing mechanical stresses is vital, whose disruption gives rise to diseases, particularly those related to ageing or physical inactivity (Figure-1).

In obesity, plasma adiponectin is reduced, which causes insulin resistance and atherosclerosis. We identified its receptors AdipoR1 and R2, and showed that they exert antiaging effects via activation of AMPK/SIRT1 and PPAR-α pathways, respectively, leading to increased mitochondria as well as decreased ectopic fat accumulation, oxidative stress and inflammation. Recently, we identified orally active small-molecule AdipoR agonist AdipoRon, which bound to AdipoR, showed very similar effects to adiponectin in muscle and liver, such as increased exercise endurance and energy expenditure, and ameliorated insulin resistance via AdipoR in obese mice, leading to healthy longevity. Most recently, we determined and reported the crystal structures of human AdipoR, which will facilitate the understanding of novel structure-function relationships and the optimization of AdipoRon as exercise mimetics.

Objective: Lipid droplets (LDs) are cytoplasmic inclusions that have a neutral lipid core with a single phospholipid layer, while excess free fatty acids and glucose in plasma are converted to triacylglycerol (TAG) and stored as LDs. However, the mechanism for the generation and growth of LDs in cells is largely unknown. This review will explain the relationship between LD formation and autophagy.

Results: LD formation accompanied by accumulation of TAG induced by starvation was largely suppressed in the hepatocytes and cardiac myocytes that cannot execute autophagy. Under starvation conditions, LDs in addition to autophagosomes were abundantly formed in the cytoplasm of these tissue cells, although autophagosomes did not appear in wild-type and autophagy-unable cardiac myocytes. Moreover, LC3 was localized on the surface of LDs and LC3-II (lipidation form) was fractionated to a perilipin-positive lipid fraction from the starved liver.

Conclusion: Taken together, these results indicate that the LC3 conjugation system is critically involved in lipid metabolism via LD formation.

The hypothalamus contains several sub-nuclei that regulate autonomic functions such as hunger and thirst. The hypothalamus is a small structure of less than 1 cubic centimeter in each hemisphere of the human brain, and very little is known about precise anatomical organization and functional properties of the hypothalamus in the human brain. In this study, in collaboration with departments of endocrinology and radiology, high-resolution fMRI was conducted, while blood glucose level was monitored (Figure-1). Cubic voxels of 1.25 mm were employed, rather than standard high-resolution fMRI of 2 mm cubic voxels, which allowed us to divide the human hypothalamus into several sub-regions using a boundary mapping method based on the resting-state functional connectivity. The defined sub-regions were used to track fMRI signal time-courses when the blood glucose level was manipulated by OGTT. Our preliminary results showed prominent signal changes after OGTT in specific sub-regions in the hypothalamus, and promise future studies of mapping autonomic functions in the human hypothalamus.

Approximately 30% of Japanese citizens will be aged 65 or older in 2020, and this ratio will be the highest worldwide. An estimated 4.6 million individuals in Japan and 44 million individuals globally have been diagnosed with dementia. Exercise has been identified as a potential means of preventing or delaying cognitive decline. Several epidemiological studies on older adults demonstrated that gait speed was associated with cognitive function. Randomized control studies on physical exercise interventions also indicated that aerobic exercise is beneficial for cognitive function. In order to determine the effects of short-term treadmill exercise on tau protein modifications, we employed a 3-week treadmill treatment using tau model mice. The results obtained showed increases in oxidative stress, microglial cell proliferation, and C-terminal tau phosphorylation. Previous studies reported that long-term treadmill treatments were beneficial. Therefore, positive compensatory changes may occur with the continuation of treadmill training in mice. The molecular mechanisms underlying the relationship between physical exercise and cognitive function still remain unknown; however, their elucidation may lead to the identification of a novel molecule, which may ultimately result in a cure for dementia.

Recent advances of MR imaging allow us to visualize the functional and structural changes of the brain not only in the patients with neurological disorders, but also in normal subjects. Sophisticated MR techniques, such as resting-state functional MR and diffusion MR imaging, can depict subtle brain changes in normal subjects before metabolic syndrome as well as brain changes after a few weeks muscle training. Minimal structural changes in the brain after repeated minor head trauma during sports are now highlighted, because advanced MR techniques can be used to show substantial changes in the brain before neurological decline.

By diffusion tensor imaging (DTI), we can explore microstructure of the tissue in vivo through analysis of water diffusion direction and restriction. DTI was developed mainly in the central nervous system to visualize the white matter tracts and their networks. Plasticity of the brain white matter has been reconfirmed with this technique. Skeletal muscles also have the direction and restriction of water diffusion and can be analyzed by DTI as well.

Recent advances of MR techniques for sportology, especially diffusion MR imaging, will be presented in this paper.

Purpose: Alzheimer disease (AD), involved the abnormal metabolism of β-amyloid and tau, is the major cause of dementia among elderly. Diabetes mellitus (DM) has been identified as a risk factor of AD. Two pathological lesions of AD, Aβ plaques and neurofibrillary tangles, are linked to neuroinflammation and lipid peroxidation, are also induced by abnormal glucose metabolism. Here, we examined the effects of experimental DM in tau transgenic mice Tg601 (overexpressing wild-type human tau) and analyzed the brain regional difference occurred due to DM in AD.

Methods: Hippocampus, midbrain and cerebellum were analyzed from streptozotocin (STZ) injected of Tg601 and non-transgenic (NTg) mice. Immunoblotting and immunohistochemistry (IHC) were performed to assess tau hyperphosphorylation, and IHC to evaluate Ionized calcium binding adaptor molecule-1 (Iba-1) and CD68 positive microglia. Inflammatory cytokines including IL-1β, IL-6, and IL-10 were assayed using multiplexed bead based immunoassay. IL-18 was measured by enzyme linked immunosorbent assay (ELISA) and lipid peroxidation products 4-hydroxy-trans-2-noneal (HNE) and malondialdehyde (MDA) by ELISA and thiobarbituric acid reactive substances assay, respectively.

Results: STZ injection induced tau hyperphosphorylation, as detected by AT8 and AT180 antibodies, in the hippocampus, but not in the cerebellum or midbrain of Tg601 and NTg mice. STZ treatment also elevated the number of Iba1-positive microglial cells, levels of IL-1β, IL-6, IL-10 and IL-18, and lipid peroxidation markers MDA or HNE in the hippocampus of the brain.

Conclusions: These results indicated that hyperglycemia-induced tau hyperphosphorylation, neuroinflammation and oxidative stress occurred more severely in the hippocampus than other parts of the brain and could contribute to selective neurodegeneration in human AD.

Background: Physical exercise has been reported as a preventive measure of Alzheimer's disease, one of the neuropathological hallmarks of which, neurofibrillary tangles, consist of hyperphosphorylated insoluble tau. Long-term treadmill exercise reduced tau hyperphosphorylation: however, it remains unknown whether short-term treadmill exercise alters tau modifications.

Aim: Here we attempted to characterize the effects of short-term treadmill exercise on tau solubility and determine its relationship with neuroinflammation using tauopathy model mice (Tg601).

Results: 3 weeks of non-shock treadmill exercise in Tg601 and non-transgenic mice markedly increased insoluble tau by increasing the phosphorylation at the tau C-terminal end, particularly at Ser396. The results of immunohistochemical analyses revealed that short-term treadmill exercise increased the number of Ionized calcium binding adaptor molecule-1 (Iba-1) positive microglia in the hippocampus. Elevations in the levels of the lipid peroxidation markers 4-hydroxy-trans-2-noneal and malondialdehyde indicated the presence of oxidative stress.

Conclusion: Our results suggested that short-term forced exercise was harmful rather than beneficial to Alzheimer’s pathology.

Purpose: Eye movements are important factors for dynamic visual acuity (DVA) that refers to the ability to perceive fine details of a moving object. When tracking a moving visual stimulus, we often combine smooth eye movements with catch-up saccades. The velocity of saccade eye movements (up to 500-600 deg/s) is much faster than smooth pursuit (usually less than 50 deg/s). Even though a tracking ability using these two kinds of eye movements is thought to play a critical role in DVA, it is still uncertain whether better DVA is associated with an ability of catch-up saccades. The first purpose of this study was to quantitatively clarify the effects of vision training on DVA and eye movements. Therefore, we repetitively measured the eye movements during DVA training and attempted to determine the effects of visual training on saccade eye movements. The second purpose was to assess the concentration of serum and plasma brain-derived neurotrophic factor (BDNF) level before and after vision training. BDNF is a member of the neurotrophin family of growth factors, which are related to the canonical Nerve Growth Factor. Previous studies have reported that moderate intensity exercise leads to increase in BDNF. However it is unknown whether BDNF level is correlated with eye movements. Therefore, we examined the correlation between BDNF level and eye movement parameters.

Methods: DVA was evaluated by a moving visual target (Landolt ring) that was projected on the front screen (HI-10; Kowa, Japan). Eye movements were detected using a video based eye tracking system (Eye Link1000; SR research, Canada). We have performed measuring DVA in five subjects (mean age; 19.0±2.6, age range; 19 to 21 years old) and analyzed saccades eye movements quantitatively using custom analytical software (Matlab; Mathworks Inc., USA). Subjects were seated in front of a screen and put their jaw on a chin supporter of our device to stabilize the head. The subjects were asked to follow the Landolt ring moving across in front of their visual field and judge the direction of the slit. We analyzed saccade latency (msec), peak velocity (deg/sec), error (deg) and a correct response rate (%). The Landolt ring moved either from right to left or left to right with constant speed of 300 deg/s. A total of eight measurements were performed for each subject. We took blood samples from each subject before and after vision training and checked serum and plasma level of BDNF.

Results: Our results demonstrated that saccade latency and error showed significant decreases and the correct response rate increased after training for five subjects. Especially for the result of correlation analysis, the correct response rate showed a correlation coefficient of 0.63 (p=0.021), indicating a stronger correlation than the other three parameters. In contrast, saccade peak velocity showed different results among subjects. For three subjects, the velocity increased while two subjects showed a decrease in velocity after training. The results of the analysis showed a significant positive correlation of the concentration of plasma BDNF level with velocity and the correct response rate. However, the results showed a significant negative correlation of the concentration of plasma BDNF level with latency and error. It was also revealed that the results of plasma and serum BDNF level were contrary to each other.

Conclusion: Our study provided several lines of evidence showing that saccade eye movements, such as latency, error and peak velocity changed after vision training. Since our results showed that visual training improved DVA, better DVA could be associated with the tracking ability using catch-up saccades. We were also able to clarify that the plasma and serum BDNF possibly affected actual eye movements.

Although it is widely accepted that cerebrovascular events associated with diabetes mellitus adversely affect the brain, it is less well known that diabetes mellitus itself or even prediabetes can also do so. In this presentation, we focus on this issue by using evidence from recent diffusion tensor neuroimaging studies of patients with diabetes mellitus or metabolic syndrome.

First, through the Sportology project, we explored the regional patterns of white matter alteration in subjects with metabolic syndrome. We also investigated whether the degree of white matter alteration was correlated with BMI. Seven middle-aged men with metabolic syndrome and seven without metabolic syndrome underwent diffusion tensor imaging. MRI scans were performed with a 3.0-T unit (Achieva; Philips Medical Systems, Best, the Netherlands). We analyzed the resultant fractional anisotropy (FA) values by using a tractbased spatial statistics technique. We subsequently measured the mean FA values of the right inferior fronto-occipital fasciculus (IFOF) in all subjects by using a tract-specific analysis. We used Pearson’s correlation coefficient to evaluate the relationship between BMI and the mean FA value in the right IFOF. In the whole-brain analysis, subjects with metabolic syndrome had significantly lower FA values than control subjects in part of the right external capsule (which is part of the right IFOF), the entire corpus callosum, and part of the deep white matter of the right frontal lobe. In the regional brain analysis, the mean FA value of the right IFOF was 0.41±0.03 in subjects with metabolic syndrome and 0.44±0.05 in control subjects. A significant negative correlation was observed between BMI and FA values in the right IFOF (r=-0.56, p<0.04). These results suggest that there are microstructural changes in the white matter of middle-aged individuals with metabolic syndrome. Our findings add to the increasing body of neuroimaging evidence on white matter alteration in patients with hypertension, diabetes, or metabolic syndrome. Microstructural alterations in the white matter of younger obese individuals may precede brain atrophy or cognitive impairment, or both, in advanced metabolic syndrome.

Second, again through the Sportology project, we explored the regional patterns of white matter alteration in 15 hypertensive middle-aged male participants and 11 normotensive controls by using diffusion kurtosis imaging (DKI)-based whole-brain analysis. DKI data were acquired by use of a single-shot, spin-echo planar imaging sequence. Mean diffusional kurtosis (MDK) values in many brain regions were higher in subjects with hypertension than in control subjects, indicating that there were widespread microstructural changes in the white matter, whereas the conventional diffusion metrics of FA did not differ significantly between subjects with hypertension and normal controls. Moreover, MDK values over the whole brain were significantly and positively correlated with systolic and diastolic blood pressure. This finding suggests that microstructural white matter changes occur in middle-aged men with hypertension, even before the onset of cerebrovascular disease. DKI might therefore be useful as a screening tool for risk of cerebrovascular disease.

DTI is completely noninvasive and is sensitive to white matter pathology in a number of disorders, including metabolic syndrome, in the human brain in vivo. Accumulated evidence highlights the need to further elucidate the relationship between metabolic syndrome and other neuronal mechanisms. A clear understanding of these relationships is crucial for managing patients with metabolic syndrome.

Background: Dilated cardiomyopathy (DCM) is one of major causes of heart failure (HF), characterized by ventricular dilatation and contractile dysfunction. In addition to HF, about 30-40% of patients with DCM die from premature death with lethal arrhythmia. To date, the exercise is considered to be one of therapy for HF as shown in the guideline for chronic HF (Japanese Society of Cardiology in 2010). However, the effects of exercise on DCM patients are still unclear, because evaluation of exercise therapy in DCM patients is associated with risks of worsening of HF or sudden cardiac death. Investigations with animal models of inherited DCM are necessary. Previously, we have established the method to evaluate the severity of HF using a mouse model of DCM (Sugihara et al. PLoS One, 2013). In the course of these studies, we found that voluntary exercise started at young age significantly prolongs survival rate of DCM mice. In this study, we investigated the effects of voluntary exercise on the cardiac function and arrhythmogenesity in DCM model mice.

Methods: We used a knock-in mouse model having one of human inherited DCM mutation, TNNT2 ΔK210, which decreases Ca2+ sensitivity of myofilaments (Du et al. Circ Res, 2007). Homozygous ΔK210 (below are called DCM mice) and wild type (WT) mice at 1 month-old were housed with a running wheel (diameter=12 cm) every 48 hours or all day long, and daily voluntary running activity was recorded. At 2 month-old, end-diastolic dimension and ejection fraction (EF) were measured by echocardiography. Heart, lung and lower extremity muscle (soleus, plantaris and gastrocnemius muscles) were excised and their weights were measured together with body weight. Gene expressions of major ion channels (Kv1.5, Kv4.2, KChiP2, Nav1.5, Cav1.2, etc.,) were quantified by real time PCR analysis.

Results and Discussion: DCM mice died with t1/2 of approximately 70 days as reported previously (Du et al, 2007). The average lifespan of the DCM mice who continued running exercise every 48 hours was about 20 days longer than that without exercise. Moreover, systolic cardiac function defined by the average EF was higher in DCM mice with exercise than in those without exercise [0.47±0.10 (n=7) vs. 0.31±0.10 (n=4), p<0.05] at 3 month-old. On the other hand, electrical remodeling such as down-regulation of multiple types of K+ channels and accessory subunits has been reported in the DCM mice and closely related to the arrhythmogenesity in them (Suzuki et al. PLoS One, 2012). Some of these expression in DCM mice starting exercise at young age were relatively preserved (n=6). We further discuss the relationship between cardiac function, electrical remodeling and leg muscle weights as a measure of exercise intensity.

Purpose: Regular bouts of endurance exercise can protect the heart against ischemia/reperfusion (I/R) injury. However, the effects of acute exercise immediately before I/R events on myocardial dysfunction remain unclear. This study examined (1) whether a single session of acute exercise reduced cardiac dysfunction after I/R, and (2) whether a single exercise session up-regulated the intracellular signaling pathways involved in cardioprotection in the rat heart.

Methods: Male Sprague-Dawley rats were divided into a sedentary control (CON) group and an exercise (EX) group. Rats in the EX group underwent one 30-min session of treadmill running. Following exercise, hearts were excised and subjected to Langendorff perfusion. To evaluate cardiac function during I/R, hearts from both groups were exposed to global ischemia (20 min) followed by reperfusion (45 min). Using western blotting, phosphorylation of Akt, protein kinase C-ε (PKCε) and glycogen synthase kinase 3-β (GSK-3β) in the hearts were analyzed.

Results: Cardiac function was significantly higher in the EX group compared with the CON group for 5-20 min after reperfusion (p<0.05). Phosphorylation of Akt, PKCε and GSK-3β in hearts of EX rats showed significant increases compared with CON rats (p<0.05). Exercise did not change expression levels of heat shock protein 72 in the heart.

Conclusions: Acute exercise prior to I/R attenuated cardiac dysfunction in the isolated rat heart. The attenuation might be due to exercise-induced activation of cardioprotective intracellular signaling.

A single bout of exercise induces a moderate increase in arterial pressure with marked tachycardia as a result of sympathoexcitation. However, the brain mechanisms underlying cardiovascular regulation during exercise still remain unknown. In this proceeding, we introduce our hypothesis that the brain histaminergic system plays an important role in regulating the cardiovascular system during exercise. The nucleus of the solitary tract (NTS) is one of the ideal brain sites for generating cardiovascular controls during exercise because it is known as a pivotal region which integrates the baroreceptor sensory information with other inputs such as muscle afferents and descending signals from the hypothalamic area. We found that activation of histamine receptor H₁ expressed in the NTS neurons induced pressor and tachycardiac responses, and that the pressor response exhibited functional plasticity after long-term daily exercise. These findings suggest that H₁ receptors in the NTS are involved in cardiovascular regulation during exercise. Since the NTS receives axons of histaminergic neurons located in the tuberomammillary nucleus (TMN) in the hypothalamus, the functional roles of TMN-NTS pathway have also been investigated. We electrically stimulated the TMN and found pressor and tachycardiac responses. Notably the pressor responses were partially inhibited by cetirizine, a H₁ receptor antagonist, microinjected into the NTS whereas we failed to see the inhibitory effects on the heart rate response. Based on all these findings, we postulate that the TMN-NTS pathway has an important role in a central feed forward mechanism underlying pressor responses to exercise.

Objective: It has been reported that psychological triggers such as emotional stress, increase the incidence of cardiovascular events. The association between soccer championships and the risk of cardiovascular events is still unclear. World Cup Soccer (WCS) involving the national team might be a strong enough trigger to induce cardiac arrhythmia. However, there are no reports which investigated the relationship between WCS and cardiac arrhythmia in the Japanese population.

Design: A multi-center retrospective observational study.

Methods: We assessed 25 patients who were evaluated ischemic changes and/or arrhythmia by 24-h Holter electrocardiography in 4 Cardiology Divisions during WCS 2014. The patients were divided into two groups [Watching group (n=7): patients who watched WCS on live-TV on June 20 (Japan vs. Greece) or July 25, 2014 (Japan vs. Colombia), and No-watching group (18 patients)]. Heart rates, arrhythmia, and ischemic changes were evaluated.

Results: There were no significant differences of clinical characteristics, frequency of premature atrial contractions, and ischemic changes between the two groups. Although there were no differences in total premature ventricular contractions (PVCs), the frequency of PVCs during matches (p<0.05) were significantly higher during live-TV in the Watching group than in the No-watching group. No sustained ventricular tachycardia or fibrillation was observed.

Conclusions: A significant association between watching WCS and the frequency of PVCs was observed. These data suggest that emotional stress while watching national team soccer matches may induce stress-related cardiovascular events.

Introduction: School athletic clubs serve as central sites of sports activities for many junior and senior high school students in Japan. School athletic clubs preserve the traditions of pre-war junior and senior high schools, and constitute a sports-education system unique to Japan. Although other countries maintain athletic clubs, only in Japan is there a system, an environment, and leaders (school teachers) under which school athletic clubs seek to win national championships. This system is characterized by the incorporation of sport within school-based education; this arrangement allows students to regularly perform athletic activities. Three million junior and senior high school students spend 700 hours each on athletic club activities annually. These facts indicate a large number of school athletic clubs performing extremely intensive physical training activities. The question thus arises: do school athletic clubs’ activities truly cultivate the minds and spirits of young athletes, given the current environment has these problems? In our study, we surveyed athletes belonging to school athletic clubs to examine relationships between concepts related to mental strength and ideas about sports. The authors specifically addressed sport commitment and resilience. Scanlan et al. proposed a theory of sport commitment, which describes athletes’ persistence in, connection with, and devotion to sports. Research has examined resilience since the 1990s; in Japan, resilience has been discussed in terms of ‘ability to recover’ and ‘restoration of strength’. Resilience has also been considered ‘mental strength’, which enables one to recover from stress or negative life events, and to recuperate after harm. Additionally, as students may experience a variety of stressors unique to school athletic clubs, stress measures specific to these clubs were used. This study aimed to investigate relationships among these factors.

Method: Anonymous questionnaire surveys were administered. Participants were students (n=203) attending private high schools in the Tokyo metropolitan district. Questionnaires were (1) Hagiwara et al.’s Commitment to Sports Scale, (2) the Resilience Scale developed by Yamagishi and revised by Oshio and Ishige et al., (3) Shibukura et al.’s Stressor Scale for High School Athletic Club Members, and (4) a face sheet inquiring whether the participant is a member of a school athletic club. For followup investigation, each participant was issued a password. Data were collected from the 11th to the 15th of May 2015.

Results: Factor analysis of Resilience Scale scores extracted five factors that differed slightly from factors reported in previous research: ‘positive future orientation and optimism’, ‘pursuit of novelty’, ‘emotional adjustment and optimism’, ‘relationship orientation’, and ‘metacognition orientation and emotional adjustment’. Factor analysis of scores on the Stressor Scale for High School Athletic Club Members extracted the same five factors as in previous research: ‘competitiveness’,‘coaches’, ‘practice time’, ‘comrades’, and ‘injury or illness’.(The rest of omitted)

The objective of this study was to examine the impact of parental support of physical activity and parents’ past levels of competitiveness in sports on parenting attitudes. The research subjects were 256 parents of freshman students in a university’s Health and Sports Science Department and Medical Department. The time period of this research was November 2014 to January 2015. Questionnaires included the Parental Support Scale, the past levels of competitiveness in sports, and the Parenting Attitude Scale. The exploratory actor analyses were conducted on the Parental Support Scale and the Parenting Attitude Scale, separately. The results revealed that the Parental Support Scale consisted of 3 factors with 4 items each (total of 12 items) and the Parenting Attitude Scale consisted of 2 factors with 4 items each (total of 12 items). The reliabilities and validities of these two scales were also assessed. In the multiple regression analyses, the Parental Support Scale was set as a dependent variable, and the Parenting Attitude Scale and the level of competitiveness in sports were set as independent variables. The analyses were conducted separately on fathers and mothers and separately on male and female children. The path models showed the gender difference between fathers and mothers and difference between male and female children, and both the parenting attitude and the level of competitiveness in sports distinctively influenced on the parental support of children’s physical activity. When we considered past levels of competitiveness in sports and parental support of physical activity as potential factors affecting parenting attitudes, the latter factor had an impact among both fathers and mothers, whereas the former factor was significant only among mothers. Parents should increase their emphasis on responsiveness when raising boys and on demandingness when raising girls to contribute to improvement in their parenting attitude.

We compared the level of physical activity, physical fitness, and obesity of adolescents among major metropolitan cities in East and Southeast Asia. A total of 12,588 valid adolescents’ data (age 12-15 years) were collected from eight major metropolitan cities in East and Southeast Asia. Analytic items included body mass index (BMI), self-reported moderate to vigorous physical activity (MVPA), and whether or not students engaged in sports club activity. Physical fitness tests included Sit-and-reach Test, Hand Grip test, 1 Minute Sit-up Test and 15 meters Progressive Aerobic Capacity Endurance Run (PACER) Test All measures of Japanese adolescents were significantly (p<0.05) greater than the other adolescents. In particular, the effect sizes relating to endurance fitness, and MVPA were much higher than the effect sizes on the other measures. These findings suggested that Japanese adolescents were the most physically fit and active in Asian adolescents.

Purpose: The purpose of this study was to validate for leg and vertical stiffness estimated by using Morin’s method.

Method: One hundred twenty seven children participated in this study. Each subject sprinted for 50 m. The motion through an interval from 30 m to 40 m was recorded with high-speed camera at 300 Hz from the sagittal plane. The running speed, contact time in stance phase and flight time were measured to estimate maximal force exerted on the foot (F_max), vertical stiffness (k’_vert) and leg stiffness (k’_leg) by Morin’s method (2005). In gold standard method (MacMahon and Cheng, 1990), vertical excursion of center of mass and leg spring length variation was calculated from digitized landmarks and ratios of F_max to vertical excursion of center of mass and to leg spring length variation were calculated as the vertical stiffness (k_vert) and leg stiffness (k_leg).

Result: All values are represented in mean value±standard deviation (SD). k’_vert was 15.51±5.97 kN/m, whereas k_vert was 17.92±6.59 kN/m. The mean difference of the k’_vert between k_vert was -2.41±2.62 kN/m. ICC between k’_vert and k_vert was 0.851 (p<0.001). Mean k’_leg and k_leg was 5.21±1.91 kN/m and 6.81±2.57 kN/m. ICC between k’_leg and k_leg was 0.642 (p<0.001), while k’_leg was highly correlated with k_leg (r=0.839). Additionally k’_leg was underestimated (-23.6%) to k_leg.

Conclusion: We could conclude that Morin’s method might be able to estimate vertical stiffness and leg stiffness in children, although vertical and leg stiffness tended to be underestimated.

Objective: The purpose of this study was to examine the relationship between birth month, physical size, motor ability, and physical activity evaluated by kindergarten teachers, of young Japanese children by using structural equation modeling.

Methods: We collected the data from 329 children (160 four-year-old children: 76 male and 84 female, and 169 five-year-old children: 85 male and 84 female). Ten teachers in charge of children’s classes in the kindergarten were administered questionnaires, and the children’s physical size, motor ability, and children’s physical activity, as determined by kindergarten teachers, were investigated. Structural equation modeling was used to examine the above-mentioned variables in each grade.

Results: The results showed significant goodness of fit in both 4- and 5-year-old children. Specifically, the model in 4-year-old children showed a significant scale, a good fit to the model according to the approximate fit indices (Goodness of Fit Index [GFI]=0.938, Adjusted Goodness of Fit Index [AGFI]=0.894, Comparative Fit Index [CFI]=0.967, and Root Mean Square Error of Approximation [RMSEA]=0.043). The model in 5-year-old children showed a significant scale and a good fit to the model according to the approximate fit indices (Goodness of Fit Index [GFI]=0.938, Adjusted Goodness of Fit Index [AGFI]=0.894, Comparative Fit Index [CFI]=0.936, and Root Mean Square Error of Approximation [RMSEA]=0.043). In both 4- and 5-year-old children, birth month influenced physical activity evaluated by kindergarten teachers, mediating physical size and motor ability.

Conclusions: We concluded that the birth months influenced children’s physical activity evaluated by kindergarten teachers through physical size and motor ability.

Objective: An important strategy for achieving healthier body compositions is to encourage lifetime physical activity (PA) participation in overweight or obese adolescents. The purpose was to compare the association between PA and obesity among adolescents in China, and to identify the factors that influence the PA and obesity.

Methods: In 2013, a cross-sectional study was involved 962 Chinese children and adolescents aged 12-16 years (mean age 14.9±0.9). The adolescents were classified as normal weight (NW), overweight (OW), and obese (OB), according to the BMI cut-offs that was determined by an obesity working in China. The adolescents were recruited for anthropometric measurements and to complete a standardized PA questionnaire. Other confounding variables such as the parents’ demographic information, and lifestyle factors were also collected through the questionnaire.

Results: Nine hundred thirty-seven valid data were collected from the adolescents. The prevalence of obesity was 8.8% (boys: 9.9%, girls: 7.5%) for junior high-school students (JS) and 7.8% (boys: 12.7%, girls: 4.3%) for high-school students (HS). Regardless of the sex and weight status, the probabilities for achieving PA for HS were less than JS. Moreover, the OW and OB groups had significantly less PA, watched more television, or used the computer more often than the NW groups (p<0.05).

Conclusion: The adolescents consistently failed to meet the established PA recommendations and supported the age-related declines in PA. In this study, we highlighted the importance of promoting PA to adolescents, especially those who are OW and OB.

Introduction: Toes are the only parts of the body connected to the ground, providing both tactile and pressure information through the plantar afferents, somatic sensation through these organs is also very important for various movements, including standing and walking. In particular, the toes control whole body posture and movement, and can generate propulsive force during walking and prevent forward falls. Toe function has been often represented as toe grip strength in various studies. Some investigators have found that low toe grip strength (TGS) is an important risk factor for falls among elderly individuals (Endo et al. 2002). The other side a decrease in children’s physical strength and athletic ability has become a problem in recent years. The present study was aimed to reveal the relationship between TGS and physical fitness in elementary school children.

Methods: From first to sixth grade 274 primary school children (men=133, women=141) were participated in this study. TGS was measured using a toe grip dynamometer (Takei Scientific Instruments, Japan). Physical performance was evaluated using MEXT’s physical fitness tests (Grip strength, sit-up, long seat type anteflexion measurement, sidesteps, multi-stage fitness test, 50-meter run, standing long jump, softball throw), manual muscle test (MMT)(Knee extension torque, knee flexion torque, hip extension torque and Hip flexion torque) and Jumping height (Rebound jump (RJ), squat jump (SQJ), counter movement jump (CMJ). The correlations for mean TGS between boys and girls were calculated using Peason’s correlation coefficient. To assess relationships between mean TGS and the selected parameters, we calculated Pearson’s correlation coefficient by sex and conducted a stepwise multiple regression analysis that included physical characteristics, physical fitness and muscle strength as explanatory valuables. For all tests, statistical significance was set at p<0.05.

Results and Discussion: Toe grip strength was significantly increased after the third grade in comparison to the first grade for both genders (p<0.01). It was observed that muscle strength of elementary school children increases with growth. It tended boys higher than girls, however, w