Evaluation of muscle strength and its relation to exercise habits in Japanese

The aim of this study was to explore muscle strength and its relation to exercise habits in Japanese. We used data from 3,018 men and 6,881 women aged 20-69 years and not using medications in a cross-sectional study. Exercise habits and muscle strength, i.e. grip strength and leg strength, were measured. Age-related changes in muscle strength were noted. Exercise habits were found in 984 men (32.6%) and 1,664 women (24.2%). For subjects of both sexes over 50 years, grip strength was significantly decreased with age. However, the ratio of leg strength to body weight significantly decreased with age as early as 30 years in men and 40 years in women. Grip strength, leg strength and the ratio of leg strength to body weight in subjects with exercise habits were significantly higher than those without exercise habits after adjusting for age in both sexes. This standard mean value may provide a useful database for evaluating muscle strength in Japanese adult subjects.</p

What Behaviors Are Important for Successful Weight Maintenance?

Purpose. To examine behavioral factors related to successful weight maintenance. Methods. Subjects were 90 middle-aged participants who attended a weight loss program and were followed for one year. The subjects were classified into either successful weight maintainers (maintained a weight loss of 5% or more from their initial weight for one year) (SWM) or unsuccessful weight maintainers (USWM), and weight control practice, stress, obstacles, support, and self-efficacy during the program and follow-up period were compared. Results. SWM had mean loss of 12% from their initial weight during the program. They showed a greater improvement in their regularity of eating, walked more, and felt less stress regarding their increased physical activity than the USWM. During the follow-up period, significantly more SWM participants had self-efficacy (for measuring weight, practicing dietary objective, and assessing the practice and keeping records), actually kept records and measured weight more than the USWM participants. In contrast, more USWM participants felt stress about measuring weight. Conclusion. In addition to a substantial initial weight loss due to an increased amount of physical activity, having a higher self-efficacy and consistently keeping records of one's activities, as well as regularly weighing themselves, may be important for successful weight maintenance

Exhaustive Exercise Enhances Immune Response To Flagellin Via Adrenaline-Mediated Up-Regulation of TLR5 Expression

Objective: We already reported that lipopolysacchride (LPS)-induced tumor necrosis factor (TNF)-α production as a bacterial infection model to induce immune response, was inhibited by exhaustive exercise. However, it remains unclear whether or not the immune response to flagellin (FG), which binds to toll like receptor 5(TLR5) and induces pro-inflammatory cytokine production, is also inhibited by this severe exercise. The aim of this study was to determine whether or not exhaustive exercise affects TNF-α productions after FG injection in mice. Methods: Both exhaustive-exercised (EX; n=12) and non-exercised (N-EX; n=12) male C3H/HeN mice were injected with FG (1 mg/kg, i.v), and blood samples were collected. In addition, to clarify the effect of catecholamine on immune response macrophage and intestinal cells after FG stimulation, RAW264 cells and Caco2 cells were cultured 30min after propranolol (Prop; β-adrenergic receptors blocker) or Ly294002 (Ly; PI3K inhibitor) treatments, and were then stimulated with adrenaline (AD; 1 μM) and FG (5 μg/ml). Moreover, the effect of Prop (10 mg/kg, n=12) on FG-induced TNF-α production in EX mice was also examined. Results: TNF-α in EX group was significantly higher than that in N-EX group after FG injection. In epithelium cells, more intensity of TLR5 localization was observed on the plasma membrane area than in the cytosol area in EX mice, but not N-EX mice. Caco2 cells, but not RAW264 cells, significantly increased the FG-induced TNF-α production using AD treatment. Moreover, Prop treatment attenuated the AD-induced TNF-α production in response to FG in Caco2 cells. Although TLR5 expression on RAW264 cells was significantly decreased after AD treatment, the expression on Caco2 cells was rapidly increased. In fact, we observed the AD-dependent TLR5 translocation from cytoplasm to cell membrane in Caco2 cells, and the membrane translocation was inhibited by Prop and Ly treatment. Moreover, the pretreatment with Prop attenuated the exercise-induced plasma TNF-α response to FG in vivo. Conclusion: Our results suggest that immune response to FG via TLR5 might be enhanced by exhaustive exercise in mice

Results from the Japan 2016 report card on physical activity for children and youth

Background: The Report Card on Physical Activity for Children and Youth aims to consolidate existing evidence, encourage more evidence-informed physical activity, and improve surveillance of physical activity. Methods: Application of Canada and Scotland Report Card methodology to Japan, adapted to Japanese circumstances and availability of data, and based on nationally representative surveys. Results: The 2016 Japan Report Card on Physical Activity for Children and Youth consists of Health Behaviors and Outcomes (7 indicators); and Influences on Health Behaviors (4 indicators). Three Health Behaviors and Outcomes received C grades (Participation in Sport; Sedentary Behavior; Recreational Screen Time; Physical Fitness), while two indicators could not be graded (Overall Physical Activity, and Active Play). The indicators Active Transportation (B) and Weight Status were favorable (A). In the Influences domain, Family Influence and Community and the Built Environment were graded as D, while the School & Childcare Settings and the Government Strategies and Investments were favorable (B). Conclusions: The Japan report card illustrated some favorable health behaviors, health outcomes, and influences. There is a need for more evidence especially on overall physical activity, active play, and community and the built environment

Relationship between peak oxygen uptake and regional body composition in Japanese subjects

AbstractPurposeTo investigate the link between peak oxygen uptake and regional body composition by dual energy X-ray absorptiometry (DEXA) in Japanese subjects.MethodsA total of 93 men (42.2 ± 12.3 years old) and 106 women (43.5 ± 12.3 years old) were enrolled in this cross-sectional investigation study. Peak oxygen uptake was measured by the breath-by-breath method. Regional body composition i.e., body fat mass, lean body mass, and body fat percentage was evaluated using DEXA. In addition, metabolic risk parameters were also evaluated.ResultsPeak oxygen uptake was 37.6 ± 8.7 mL/kg/min in men and 31.1 ± 6.4 mL/kg/min in women, and decreased with age in both genders. Peak oxygen uptake was significantly correlated with total body fat percentage (men: r = −0.684, p < 0.0001; women: r = −0.681, p < 0.0001). These associations remained even after adjusting for age and total lean body mass. However, peak work rate was positively and significantly correlated with leg lean body mass.ConclusionPeak oxygen uptake was closely correlated with total body fat percentage in both genders. Aerobic exercise as well as leg resistance training might be useful for improving peak oxygen uptake in Japanese subjects

The Q223R polymorphism in the leptin receptor associates with objectively measured light physical activity in free-living Japanese

AbstractPhysical activity (PA) is associated with reductions in the risk of all-cause mortality and in the prevalence of cardiovascular disease and stroke. Nevertheless, a large proportion of the general population may not be sufficiently active. PA level has been reported to be influenced by genetic factors, and we investigated whether Q223R polymorphism in the leptin receptor (LEPR) gene was associated with PA level. A total of 556 Japanese adults aged 24–65years old participated in this cross-sectional study. The duration and intensity of PA were objectively evaluated by triaxial accelerometry. Q223R polymorphism was determined by the TaqMan method. The distribution of Q223R polymorphism was: QQ 0.7%, QR 22.6%, and RR 76.6%. The relation between the LEPR genotype and PA level was analyzed by ANCOVA with age and sex as covariates in the Q dominant genetic model. There were significant differences between LEPR genotypes and the time spent in light PA or inactive time. The subjects with RR genotype showed significantly shorter time spent in light PA (RR genotype: 559.4±102.9min/day, QQ/QR genotype: 579.9±103.1min/day) and longer inactive time (RR genotype: 815.5±107.5min/day, QQ/QR genotype: 792.3±107.7min/day) than the subjects with QQ/QR genotype (P<0.05). There were no such differences in the time spent in moderate or vigorous PA. These results suggest that the variety of PA level, especially spontaneous PA in humans, is partly caused by diversity in the LEPR gene

Linkage between Oxygen Uptake at Ventilatory Threshold and Muscle Strength in Subjects with and without Metabolic Syndrome

We evaluated the linkage between oxygen uptake at the ventilatory threshold (VT) and muscle strength in subjects with and without metabolic syndrome. We used data of 226 Japanese men with metabolic syndrome and 265 Japanese men without the syndrome. Metabolic syndrome has recently been defined by a new criterion in Japan. Oxygen uptake at VT and muscle strength, i.e. grip strength and leg strength were measured. Oxygen uptake at VT and muscle strength/body weight were found to be significantly lower in subjects with metabolic syndrome than in those without the syndrome. However, the differences did not reach significant levels after adjusting for leg strength/body weight or oxygen uptake at VT. A combination of aerobic exercise and resistance training might be considered for preventing and improving metabolic syndrome.</p

肥満解消のための無作為介入研究による脂肪量とアディポサイトカインの変化

Adipocytokines arebioactive substances synthesizedand secretedbyfat cell. Previous studies have reported an association between weight loss and adipocytokines. However, these studies are inconsistent and they have not clarified the relationship between weight regain and changes in circulating levels of adipocytokines. In this study, we analyzed the relationship between weight and fat volume changes and adipocytokines. The subjects were 235obese people recruited in the Saku Control Obesity Program (SCOP). Participants were randomly assigned to either immediate (Group A) or delayed (Group B, control group). Group A participants were followed for another two years after completion of the one year intervention. As controls, Group B participants received the same intervention as Group A after a delay of one year. Then they were followed up for one year. The intervention consisted in a one-year lifestyle program to induce weight loss, based on a cognitive-behavioral approach. After the first year of the study, body weight, BMI, body fat and abdominal fat areas were significantly lower in group A participants, compared to controls. After the intervention, leptin levels were significantly lowered both in men and women. After one year follow-up, both men and women re-gained about 1.5 kg body weight on average. BMI, waist circumference, fat areas by CT and HBA1c significantly increased during the follow-up period. The change of adipocytokine levels by analysis of the quartile of body weight decrease and regain revealed that increased adiponectin and decreased leptin was noteworthy for weight reduction, while increase of leptin influenced the weight regain. In conclusion, our results suggest that leptin could have broad effects on the distribution off at tissues and on lipid metabolism. Leptin inversely associated with adiponectin, which in turn was necessary to decrease body weight. In particular, leptin decreased remarkably in the process of weight reduction, and its increase seemed to be related in weight regain. The observed increase of adiponectin seemed to be induced by reduction in fat volume

Effect of combined resistance and aerobic training on reactive hyperemia in men

Abstract Reduced response to reactive hyperemia (RH) in the extremities reflects impaired endothelium-dependent vasodilation of the microvasculature. The aims of the present study were to determine whether resistance training and a combination of aerobic and resistance training increase the endothelial vasodilation of the forearm assessed by RH. A total of 39 young men were assigned to either high-intensity resistance training (HIR; six types of exercises, 80% 1RM 9 10 repetitions 9 3 sets, n = 14) or moderate-intensity resistance training (MIR; six types of exercises, 50% 1RM 9 16 repetitions 9 3 sets, n = 14) or a combination of high-intensity resistance training and moderate-intensity endurance training (COMBO; HIR and 60% maximal heart rate 9 30 min, n = 11) groups. We measured forearm blood flow response to RH before and after 4 months of exercise intervention. All training groups increased maximal strength in all muscle groups tested (all P \ 0.05). After 4 months of training, the forearm blood flow during RH increased significantly in the MIR and COMBO groups, from 57 ± 4 to 66 ± 7 ml/min per 100 ml tissue and from 59 ± 6 to 74 ± 8 ml/min per 100 ml tissue, respectively (both P \ 0.05). There was no change in the response to RH in the HIR groups. In conclusion, the findings in this study demonstrate that combined resistance and aerobic training may affect the vasoreactivity response to RH in the forearm, but not resistance training alone

Dose-response relationship between sports activity and musculoskeletal pain in adolescents.

Physical activity has multiple health benefits but may also increase the risk of developing musculoskeletal pain (MSP). However, the relationship between physical activity and MSP has not been well characterized. This study examined the dose-response relationship between sports activity and MSP among adolescents. Two school-based serial surveys were conducted 1 year apart in adolescents aged 12 to 18 years in Unnan, Japan. Self-administered questionnaires were completed by 2403 students. Associations between time spent in organized sports activity and MSP were analyzed cross-sectionally (n = 2403) and longitudinally (n = 374, students free of pain and in seventh or 10th grade at baseline) with repeated-measures Poisson regression and restricted cubic splines, with adjustment for potential confounders. The prevalence of overall pain, defined as having pain recently at least several times a week in at least one part of the body, was 27.4%. In the cross-sectional analysis, sports activity was significantly associated with pain prevalence. Each additional 1 h/wk of sports activity was associated with a 3% higher probability of having pain (prevalence ratio = 1.03, 95% confidence interval = 1.02-1.04). Similar trends were found across causes (traumatic and nontraumatic pain) and anatomic locations (upper limbs, lower back, and lower limbs). In longitudinal analysis, the risk ratio for developing pain at 1-year follow-up per 1 h/wk increase in baseline sports activity was 1.03 (95% confidence interval = 1.02-1.05). Spline models indicated a linear association (P < 0.001) but not a nonlinear association (P ≥ 0.45). The more the adolescents played sports, the more likely they were to have and develop pain.This study was supported by a Grant-in-Aid from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan. MK is supported by a JSPS Postdoctoral Fellowship for Research Abroad. FI is supported by the Medical Research Council Epidemiology Unit (MC_UU_12015/1; MC_UU_12015/5).This is the final version of the article. It first appeared from Wolters Kluwer via http://dx.doi.org/10.1097/j.pain.000000000000052