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There is no evidence of the effect of exercise training on human brown-like adipose tissue vascular density (BAT-d). Here, we report whether whole-body strength training (ST) in a cold environment increased BAT-d. The participants were 18 men aged 20–31 years. They were randomly assigned to two groups: one that performed ST twice a week at 75% intensity of one-repetition maximum for 10 weeks during winter (EX; n = 9) and a control group that did not perform ST (CT; n = 9). The total hemoglobin concentration in the supraclavicular region determined by time-resolved near-infrared spectroscopy was used as a parameter of BAT-d. ST volume (Tvol) was defined as the mean of the weight × repetition × sets of seven training movements. The number of occasions where the room temperature was lower than the median (NRcold) was counted as an index of potential cold exposure during ST. There was no significant between-group difference in BAT-d. Multiple regression analysis using body mass index, body fat percentage, NRcold, and Tvol as independent variables revealed that NRcold and Tvol were determined as predictive of changes in BAT-d. An appropriate combination of ST with cold environments could be an effective strategy for modulating BAT.

The purpose of this study was to compare the temporal increase in muscle cross-sectional area (CSA) as the acute response of resistance exercise (RE) between resistance-trained and untrained groups and investigate the factors that affect the muscle CSA. Resistance-trained ( n = 14) and untrained ( n = 14) subjects performed four kinds of triceps brachii RE. Muscle CSA and intracellular hydration (IH), were measured prior to and 5-, 30-, and 60-minute after RE. Pearson's correlation coefficient was calculated to clarify the relationships among percent increases in muscle CSA and IH, area under the Oyx-Hb curve, blood lactate concentration, and % maximum voluntary contraction (MVC)-root-mean-square (RMS) of electromyogram (EMG). At 5-minute after RE, muscle CSA increased significantly to 120.2 ± 6.3% in the resistance-trained group and 105.5 ± 2.3% in the untrained group ( p < .01). However, neither group showed a significant difference between the values before and 30-minute after RE. In the resistance-trained group, there was a significant increase in IH at 5-minute post-RH ( p < .01), and correlations were found between percent increases in muscle CSA and IH ( r = 0.70, p < .01), area under the Oxy-Hb curve ( r = 0.77, p < .01), and % MVC-RMS of EMG ( r = 0.72, p < .01). The findings of this study suggest that measurements of muscle CSA in studies of muscle hypertrophy should be performed 30-minute or more after the last resistance exercise session, and muscle pump exercises should be conducted just before participation in bodybuilding, and physique contests.

Background/objectives The thermogenic function of brown adipose tissue (BAT) is generally activated in winter and tightly regulated through various metabolic processes. However, the mechanisms mediating these changes have not been elucidated in humans. Here, we investigated the relationships between BAT density (BAT-d) and lipid metabolites in plasma from men and women in the winter and summer. Subjects/methods In total, 92 plasma samples were obtained from 23 men and 23 women, aged 21–55 years, on two different occasions (summer and winter). Lipid metabolites were comprehensively quantified using liquid chromatography-time-of-flight-mass spectrometry. BAT-d was evaluated by measuring total hemoglobin concentrations in the supraclavicular region using near-infrared time-resolved spectroscopy. Anthropometric parameters, such as the percentage of whole body fat and visceral fat area (VFA), were evaluated. Factors influencing BAT-d were investigated by univariate and multivariate regression analyses. Results A variety of metabolite peaks, such as glycerophospholipids (168 peaks), steroids and derivatives (78 peaks), fatty acyls (62 peaks), and glycerolipids (31 peaks), were detected. Univariate regression analysis, corrected by false discovery rate to yield Q values, revealed significant correlations in BAT-d and phosphatidylethanolamine (PE(46:2), r = 0.62, Q = 4.9 × 10−2) in the summer, androgens (r = 0.75, Q = 7.0 × 10−3) in the winter, and diacylglycerol (DG(36:1), r = −0.68, Q = 4.9 × 10−2) in the summer in men, but not in women. Multivariate regression analysis in the winter revealed a significant correlation between BAT-d and plasma androgens (P = 5.3 × 10−5) in men and between BAT-d and VFA (P = 2.2 × 10−3) in women. Conclusions Certain lipids in plasma showed unique correlations with BAT-d depending on sex and season. BAT-d showed a specific correlation with plasma androgens in men in the winter.

Androgen hormones are important compounds related to body composition and exercise performance in athletes. The intake of Dioscorea esculenta, known as lesser yam, contains diosgenin and resistance training have been shown to normalize the secretion of androgen hormones. This study aimed to clarify the level of androgen hormone secretion and the effects of Dioscorea esculenta intake with resistance training on muscle hypertrophy and strength in athletes. First, in a cross-sectional study, we compared the serum androgen hormone [dehydroepiandrosterone (DHEA), testosterone, and 5α-dihydrotestosterone (DHT)] levels between sprint athletes (n = 15) and non-athletes (n = 15). Second, in an 8-week intervention study, sprint athletes were randomly divided into 2 groups: resistance training with placebo (n = 8) or with Dioscorea esculenta (2,000 mg/day) intake (n = 7). The serum DHEA, free testosterone, and DHT levels were lower in athletes than in non-athletes. Dioscorea esculenta intake combined with resistance training increased the arm fat-free mass, the 1 repetition maximum of deadlift and snatch, and the serum DHEA, free testosterone, and DHT levels, compared with resistance training and placebo intake. The results suggested that Dioscorea esculenta intake combined with resistance training has further effects on muscle hypertrophy and strength in athletes by restoring secretion of androgen hormones.

[Purpose] The purpose of this study was to determine the efficacy of using a cold pack while doing resistance exercises for enhancing muscle strength and muscle hypertrophy through decreased intramuscular oxygenation and/or increased myoelectric activity. [Participants and Methods] Twenty-four resistance-trained males (age: 26.4 ± 8.4 years, height: 169.3 ± 5.2 cm, body weight: 74.7 ± 8.8 kg) involved in this study. All the participants completed two experimental sessions in random order (cold pack resistance exercise and resistance exercise) with a 3-day interval. Four types of resistance exercises (4 sets × 8 repetitions with an 8-repetition maximum) targeting the right triceps brachii muscle were performed in both the experimental sessions. [Results] The percentage baseline oxyhemoglobin/myoglobin level during resistance exercise was significantly lower, the half-recovery time of muscle oxygenation in intervals between sets was significantly longer, and the myoelectric activity was significantly higher in the cold pack resistance exercise than in the resistance exercise session. [Conclusion] The results suggest that using a cold pack with resistance exercises is effective in inducing intramuscular deoxygenation and increasing myoelectric activity and may be useful for increasing muscle strength and inducing hypertrophy.

PURPOSE The physiological response induced by acute prolonged sitting is not fully understood. Therefore, we examined the effects of 8-h constant sitting on microcirculation and associated factors in the lower extremity among healthy males. We also evaluated the protective effects of lower-pressure thigh-length elastic compression garments on these parameters. METHODS Nine healthy males (age, 22.6 ± 1.4 years; body mass index, 22.4 ± 1.8 kg·m-2) completed the 8-h constant sitting experiment. Following baseline measurements, each subject was randomized to wear a lower-pressure elastic garment on the right or left leg from the inguinal region to the ankle joint, with the non-compressed contralateral leg as a control. Circumferences of the calf and malleolus, extracellular water contents, blood flow and shear rate of the dorsal metatarsal artery, and oxygen dynamics in the gastrocnemius muscles were measured in both extremities before, during, and after 8-h constant sitting. RESULTS Compared with baseline values, 8-h constant sitting caused enlargement of circumferences (calf, 2.4 ± 0.7%; malleolus, 2.7 ± 1.4%), retention of extracellular water in lower extremity muscles (10.1 ± 1.78%), deterioration of the blood flow (61.4 ± 16.2% of baseline) and shear rate of the dorsal metatarsal artery, and decrease in oxygenated hemoglobin and total hemoglobin levels in the gastrocnemius muscle (p < 0.05, respectively). When subjects wore the lower-pressure thigh-length compression garment, a significant reduction of these effects was observed (p < 0.05, for all). CONCLUSION Prolonged sitting for 8 h induced edema, as well as deterioration of the arterial blood flow, shear rate, and microcirculation in lower limb muscles. Conversely, application of the lower-pressure elastic garment successfully prevented the pathophysiologic deterioration associated with prolonged sitting.

Introduction Regular aerobic exercise reverses aging-induced deterioration of arterial stiffness via an increased arterial nitric oxide (NO) production. Concurrently, asymmetric dimethylarginine (ADMA), an endogenous inhibitor of NO synthase, was decreased by aerobic exercise training. A recent study showed that the NOx/ADMA ratio reflects endothelial function and may be an index of the states of cardiovascular disease. However, whether changes in the NOx/ADMA ratio by aerobic exercise training are associated with a decrease in arterial stiffness in healthy middle-aged and older male and female adults remains unclear. Purpose This study aimed to clarify whether the relationship between plasma ADMA and NOx levels affected aerobic exercise training-induced reduction of arterial stiffness in middle-aged and older adults. Additionally, we examined whether the effect of AT on circulating ADMA levels differed according to sex. Methods Thirty-one healthy middle-aged and older male and female subjects (male = 13, female = 18, 66.4±1.3 years) participated in the study. The subjects were randomly divided into 2 groups: a training group (n=16 [male = 6 / female = 10], 64.8±2.0 years) and a control group (n=15 [male = 7 / female = 8], 68.1±1.6 years). Subjects in the training group performed the AT program, which consisted of cycling on a leg ergometer at 60–70% of peak oxygen uptake (V(·)O2peak)for 45 min/day, 3 days/week for 8 weeks. Before and after the 8-week aerobic exercise training intervention, V(·)O2peak, plasma ADMA levels and plasma NOx levels were measured in all subjects. Also, carotid β-stiffness as an index of arterial stiffness was determined with ultrasonography. Results Aerobic exercise training significantly increased V(·)O2peak (P Conclusion These results suggest that higher NOx/ADMA ratio affects aerobic exercise training-induced reduction of arterial stiffness, regardless of sex in middle-aged and older adults. Funding Acknowledgement Type of funding sources: Other. Main funding source(s): This work was supported by Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science, and Technology of Japan

Background Adropin is a peptide hormone that promotes nitric oxide (NO) production via activation of endothelial NO synthase (eNOS) in endothelial cells. Its circulating levels are reduced with aging and increased with aerobic exercise training (AT). Using a mouse model, we hypothesized that AT restores aging‐associated reductions in arterial and circulating adropin and improves adropin‐induced NO‐dependent vasorelaxation. Further, we hypothesized these findings would be consistent with data obtained in elderly humans. Methods and Results In the animal study, 50‐week‐old SAMP1 male mice that underwent 12 weeks of voluntary wheel running, or kept sedentary, were studied. A separate cohort of 25‐week‐old SAMP1 male mice were used as a mature adult sedentary group. In the human study, 14 healthy elderly subjects completed an 8‐week AT program consisting of 45 minutes of cycling 3 days/week. In mice, we show that advanced age is associated with a decline in arterial and circulating levels of adropin along with deterioration of endothelial function, arterial NO production, and adropin‐induced vasodilation. All these defects were restored by AT. Moreover, AT‐induced increases in arterial adropin were correlated with increases in arterial eNOS phosphorylation and NO production. Consistently with these findings in mice, AT in elderly subjects enhanced circulating adropin levels and these effects were correlated with increases in circulating nitrite/nitrate (NOx) and endothelial function. Conclusions Changes in arterial adropin that occur with age or AT relate to alterations in endothelial function and NO production, supporting the notion that adropin should be considered a therapeutic target for vascular aging. Registration URL: https://www.umin.ac.jp ; Unique identifier: UMIN000035520.

Near-infrared spectroscopy (NIRS) has become an increasingly valuable tool to monitor tissue oxygenation (Toxy) in vivo. Observations of changes in the absorption of light with Toxy have been recognized as early as 1876, leading to a milestone NIRS paper by Jobsis in 1977. Changes in the absorption and scatting of light in the 700–850-nm range has been successfully used to evaluate Toxy. The most practical devices use continuous-wave light providing relative values of Toxy. Phase-modulated or pulsed light can monitor both absorption and scattering providing more accurate signals. NIRS provides excellent time resolution (~ 10 Hz), and multiple source–detector pairs can be used to provide low-resolution imaging. NIRS has been applied to a wide range of populations. Continued development of NIRS devices in terms of lower cost, better detection of both absorption and scattering, and smaller size will lead to a promising future for NIRS studies.

The importance of brown adipose tissue (BAT) is well recognized in healthy infants and children. However, information regarding age-related changes in BAT vascular density (BAT-d) and the impact of BAT-d on body adiposity are lacking. This study aimed to evaluate the normal values of BAT-d, factors influencing BAT-d, and the impact of BAT-d on body adiposity in healthy infants and children.This study included 240 participants (127 girls and 113 boys) aged 1 month to 5 years. The tissue total hemoglobin concentration in the supraclavicular region adjusted according to the subcutaneous adipose tissue thickness (SAT) ([total-Hb-Adj]The [total-Hb-Adj]The [total-Hb-Adj]

This study examined the relationship between plasma amino acid (AA) concentrations, including branched-chain AAs, and brown adipose tissue density (BAT-d). One hundred and seventy-three subjects (69 men, 104 women) aged 22–68 years were recruited during the winter season. AAs were comprehensively quantified using liquid chromatography-time-of-flight-mass spectrometry. The total hemoglobin concentration in the supraclavicular region ([total-Hb]sup), an indicator of BAT-d, was assessed using near-infrared time-resolved spectroscopy. Anthropometric parameters, including age, percentage of body fat, and visceral fat, were evaluated. Factors associated with higher (≥74 µM) or lower (r = 0.73, p = 0.015) and women (r = 0.58, p = 0.079) and for men (r = 0.82, p = 0.0070) and women (r = 0.70, p = 0.020), respectively. A combination of anthropometric parameters and plasma AA concentrations could be a reliable biomarker for higher and lower BAT-d.

[Purpose] Aerobic exercise training (AT) reverses aging-induced deterioration of arterial stiffness via increased arterial nitric oxide (NO) production. Asymmetric dimethylarginine (ADMA), an endogenous inhibitor of NO synthase, was decreased by AT. However, whether AT-induced changes in ADMA levels are related to changes in nitrite/nitrate (NOx) levels remains unclear. Accordingly, we aimed to clarify whether the relationship between plasma ADMA and NOx levels affected the AT-induced reduction of arterial stiffness in middle-aged and older adults. [Methods] Thirty-one healthy middle-aged and older male and female subjects (66.4 ± 1.3 years) were randomly divided into two groups: exercise intervention and sedentary controls. Subjects in the training group completed an 8-week AT (60%-70% peak oxygen uptake [V4O2peak] for 45 min, 3 days/week). [Results] AT significantly increased VO2peak (P < 0.05) and decreased carotid β-stiffness (P < 0.01). Moreover, plasma ADMA levels were significantly decreased while plasma NOx levels and NOx/ADMA ratio were significantly increased by AT (P < 0.01). Additionally, no sex differences in AT-induced changes of circulating ADMA and NOx levels, NOx/ADMA ratio, and carotid β-stiffness were observed. Furthermore, the AT-induced increase in circulating ADMA levels was negatively correlated with an increase in circulating NOx levels (r = -0.414, P < 0.05), and the AT-induced increase in NOx/ ADMA ratio was negatively correlated with a decrease in carotid β-stiffness (r = -0.514, P < 0.01). [Conclusion] These results suggest that the increase in circulating NOx with reduction of ADMA elicited by AT is associated with a decrease in arterial stiffness regardless of sex in middle-aged and older adults.

Introduction Cardiovascular disease risk augments with advance of age. The mechanism of the increased cardiovascular disease risk by aging is related to attenuation of arterial function via endothelium-derived relaxing factor, such as nitric oxide (NO). Recently, apelin and adropin have identified as NO-upregulated hormones, whereas augmented secretion of asymmetric dimethylarginine (ADMA) have identified as NO-downregulated hormones. However, the effects of exercise training-induced changes in NO-regulated hormones on the reduction of arterial stiffness via NO productions remain unclear. Purpose This study aimed to determine the time-dependent changes in NO-regulated hormones related to exercise-training effects of arterial stiffness via NO productions in healthy middle-aged and older adults. Methods Thirty-two Japanese healthy middle-aged and older subjects (67±1 years) were randomly divided into two groups: exercise intervention and sedentary controls. Subjects in the training group completed 8-week of aerobic exercise training (60–70% peak oxygen uptake [VO2peak] for 45 min, 3 days/week). We evaluated plasma nitrite/nitrate (NOx), apelin, and ADMA levels, serum apelin level and carotid-femoral pulse wave velocity (cfPWV) as an index of arterial stiffness, measured every 2 weeks for 8-week in the training group. Results cfPWV was gradually declined from baseline to 8-week and significantly decreased from baseline at weeks 6 (P Conclusions These results suggest that the NO-upregulated hormones (apelin and adropin) were increased at the early stage of exercise training intervention and NO-downregulated hormone (ADMA) was decreased at the late stage of exercise training intervention, and these changes in NO-regulated hormones may be contributed to the reduction of arterial stiffness in the middle-aged and older adults. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): This work was supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan.

PURPOSE Near-infrared spectroscopy (NIRS), performed with a commonly available noninvasive tissue oxygenation monitoring device, is based on the modified Beer-Lambert law (MBLL). Although NIRS based on MBLL (NIRSMBLL) assumes that the optical path length (PL) is constant, the effects of changes in PL during exercise on muscle oxygenation calculated by MBLL are still incompletely understood. Thus, the purposes of this study were to examine the changes in optical properties during ramp incremental exercise and to compare muscle oxygen dynamics measured by time-resolved NIRS with those calculated based on MBLL. METHODS Twenty-two healthy young men performed ramp incremental cycling exercise until exhaustion. Optical properties (reduced scattering coefficient and PL) and absolute oxygenated, deoxygenated, and total hemoglobin and myoglobin concentrations (oxy[Hb + Mb], deoxy[Hb + Mb], and total[Hb + Mb], respectively) at the vastus lateralis were continuously monitored by a three-wavelength (763, 801, and 836) time-resolved NIRS device. The values of oxy-, deoxy-, and total[Hb + Mb] were then recalculated by assuming constant PL. RESULTS PL at all wavelengths statistically significantly shortened during exercise. In particular, PL at 763 nm was greatly shortened, and the average changes during exercise were a 9.8% ± 3.1% reduction. In addition, significant differences in the kinetics of oxy-, deoxy-, and total[Hb + Mb] between directly measuring PL and assuming constant PL were found. The average changes in measured PL and assuming constant PL-deoxy[Hb + Mb] were increases of 28.8 ± 16.0 μM and increases of 16.4 ± 9.3 μM, respectively. CONCLUSION Assuming constant PL in NIRSMBLL significantly underestimated actual muscle oxy/deoxygenation as compared with measurements obtained by real-time PL determination. The percent degree of the underestimated oxy/deoxygenation was greater than the percent degree of the changes in PL.

Brown adipose tissue (BAT) plays a role in adaptive thermogenesis in response to cold environments and dietary intake via sympathetic nervous system (SNS) activation. It is unclear whether physical activity increases BAT density (BAT-d). Two-hundred ninety-eight participants (age: 41.2 ± 12.1 (mean ± standard deviation), height: 163.6 ± 8.3 cm, weight: 60.2 ± 11.0 kg, body mass index (BMI): 22.4 ± 3.0 kg/m2, body fat percentage: 25.4 ± 7.5%) without smoking habits were categorized based on their physical activity levels (a group performing physical activities including walking and moderate physical activity (WM) and a group performing WM + vigorous-intensity physical activities (VWM)). We measured the total hemoglobin concentration ([Total-Hb]) in the supraclavicular region, an index of BAT-d, and anthropometric parameters. [Total-Hb] was significantly higher in VWM than WM for all participant groups presumably owing to SNS activation during vigorous-intensity physical activities, and unrelated to the amount of total physical activity levels. Furthermore, multiple regression analysis revealed that BAT-d was related to visceral fat area and VWM in men and related to body fat percentage in women. We conclude that vigorous-intensity physical activities are associated with high BAT-d in humans, especially in men.

There is little consensus regarding the impacts of physical activity and nutrient intake on bone mineral density (BMD) in subjects with high or low levels of arterial stiffness. This study was performed to investigate whether physical activity and nutrient intake are associated with BMD in middle-aged women with high levels of arterial stiffness. The study population consisted of middle-aged women aged 40&ndash, 64 years (n = 22). BMD was assessed by dual-energy X-ray absorptiometry. Carotid-femoral pulse wave velocity (cf-PWV) was used as an indicator of arterial stiffness. Subjects were divided into two groups by median cf-PWV. Physical activity in free-living conditions was evaluated using a triaxial accelerometer. Nutrient intake was also measured using the brief-type self-administered diet history questionnaire. In the High-PWV group, BMD showed a significant negative correlation with age. Using a partial correlation model, BMD was associated with the number of steps and unsaturated fatty acid intake in the High-PWV group. These results suggest that BMD in middle-aged women with high levels of arterial stiffness may be associated with both the number of steps and nutritional intake. Recommendations of physical activity and nutritional intake for the prevention of osteopenia should include consideration of arterial stiffness.

Funding Acknowledgements Supported by Grants-in-Aid for Scientific Research (#17H02182, #16K13059, M. Iemitsu; #18J01024, S. Fujie) Introduction Aging is well known to elevate risks of cardiovascular diseases. As a mechanism of these increased risks with aging, a reduction of nitric oxide (NO) production via augmented secretion of asymmetric dimethylarginine (ADMA), an endogenous inhibitor of NO synthesis is related. Habitual aerobic exercise has shown to improve secretory unbalance of endothelium-derived regulating factors with aging, such as increase in NO and decrease in ADMA, resulting in the reduction of arterial stiffness. However, the time course of improvement in secretory unbalance of NO and ADMA productions in response to exercise training in middle-aged and older adults remains unclear. Purpose This study aimed to determine the time course of changes in plasma nitrite/nitrate (NOx) and ADMA levels related to exercise-training effects of arterial stiffness in healthy middle-aged and older adults. Methods Thirty-two Japanese healthy middle-aged and older subjects (67 ± 1 years) were randomly divided into two groups: exercise intervention and sedentary controls. Subjects in the training group completed 8-week of aerobic exercise training (60-70% peak oxygen uptake [VO2peak] for 45 min, 3 days/week). We evaluated plasma NOx and ADMA concentrations and carotid-femoral pulse wave velocity (cfPWV) as an index of arterial stiffness, measured every 2 weeks for 8-week in the training group. Results cfPWV was gradually declined from baseline to 8-week and significantly decreased from baseline at weeks 6 (P < 0.05) and 8 (P < 0.01). Plasma NOx level was gradually elevated during exercise intervention and significantly increased from baseline at weeks 6 (P < 0.05) and 8 (P < 0.01). Interestingly, plasma ADMA level was significantly decreased at 8-week intervention (P < 0.05). Furthermore, the exercise training-induced reduction in plasma ADMA level was negatively correlated with the change in plasma NOx level before and after the 8-week (r = -0.483, P < 0.05). The exercise training-induced change in plasma ADMA concentration was positively correlated with training-induced change in cfPWV before and after the 8-week (r = 0.633, P < 0.01). Additionally, there was a negative correlation between the changes in plasma NOx level and cfPWV before and after the 8-week (r = -0.642, P < 0.05). Conclusions These results suggest that habitual aerobic exercise can normalize the secretory unbalance of NO and ADMA productions in 6 to 8 weeks, and these balance normalizations may be contributed to the reduction of arterial stiffness in the middle-aged and older adults.

Adiponectin regulates endothelial nitric oxide synthase in endothelial cells, and body fat loss by aerobic exercise training promotes adiponectin secretion. Recently, C1q/tumor necrosis factor-related proteins (CTRPs) have been identified as novel adipokines and are paralogs of adiponectin, but the association between exercise training-induced reduction of arterial stiffness and circulating CTRPs levels remains unclear. This study aimed to clarify whether the reduction of arterial stiffness in middle-aged and older adults is associated with the change in serum levels of CTRPs induced by exercise training. A total of 52 middle-aged and older participants were randomly divided into two groups: a training group ( n = 26) and a sedentary control group ( n = 26). Participants in the training group completed 8 wk of aerobic exercise training (60–70% peak oxygen uptake for 45 min, 3 days/wk). The reduction of percent whole body fat, abdominal visceral fat area, and carotid-femoral pulse-wave velocity (cfPWV) was significantly greater in the training group than in the control group ( P < 0.05). Moreover, the increase in serum adiponectin, CTRP3, and CTRP5 from baseline to 8 wk was significantly higher in the training group compared with the control group ( P < 0.05). Additionally, the training-induced change in cfPWV was negatively correlated with the training-induced change in serum adiponectin, CTRP3, and CTRP5 levels ( r = −0.51, r = −0.48, r = −0.42, respectively, P < 0.05), and increased plasma nitrite/nitrate level by exercise training was correlated only with adiponectin levels ( r = 0.41, P < 0.05). These results suggest that the exercise training-induced increase in serum CTRPs levels may be associated with the reduction of arterial stiffness in middle-aged and older adults.

We examined effects of high-intensity training on chemically induced aberrant crypt foci (ACF) in rat colon. We also investigated mechanisms that may underlie the results obtained, with a focus on secreted protein acidic and rich in cysteine (SPARC), which has been proposed as an exercise-related factor of colon cancer prevention.After an administration of 1,2-dimethylhydrazine, F344 rats executed high-intensity intermittent swimming training (HIIST) (twelve 20-s swimming with a weight [16% body weight] with 10-s pauses between the bouts) 5 d·wk for 4 wk. The acute and chronic effects of the HIIST on SPARC were evaluated in rats. We evaluated the in vitro and in vivo effects of 5' AMP-activated protein kinase (AMPK) activator on SPARC in rat serum and epitrochlearis muscle. In human subjects, we determined serum SPARC after exhaustive bicycling consisting of six to seven bouts of exercise at 170% V˙O2max with 10-s rests between the bouts (high-intensity intermittent bicycling [HIIB]). The SPARC mRNA in human vastus lateralis was measured before and after the HIIB for 4 d·wk for 6 wk (HIIB-training [HIIBT]).The numbers of ACF were lower in the HIIST (47 ± 22) compared with the control (122 ± 47) rats (P0.05). SPARC in epitrochlearis and serum after HIIS of the trained rat was higher than that in the control resting rats. In vitro and vivo AMPK stimulation increased mRNA and SPARC protein in rat epitrochlearis, respectively. The human serum SPARC after the HIIB was elevated. SPARC mRNA in human muscle was elevated after the HIIBT.The results demonstrated that HIIST inhibits 1,2-dimethylhydrazine-induced colon ACF development. This effect may be explained by SPARC induction by the exercise intensity-related factor AMPK, potentially explaining the preventive effects of high-intensity intermittent exercise training against colon cancer.

Exercise-induced changes in executive function affect the control of action in a dynamic environment. This study aimed to examine the effect of sustained high-intensity exercise on executive function. Nine healthy male and female participants (age, 21-28 years) completed an exercise session with 65-min treadmill running at 75% VO2max. Executive function was assessed before and after exercise with the Stroop Color and Word Test that included congruent and incongruent conditions. The reaction time and response accuracy of the test were measured, and the task difficulty was controlled by adjusting the stimulus duration so that each participant could maintain at least 80% response accuracy to exclude the effect of a speed–accuracy trade-off. The levels of plasma norepinephrine and adrenocorticotropic hormone were examined. A significant interaction with the reaction time was found (condition × time, P = 0.024), in which the reaction time significantly increased after exercise only in the incongruent condition (P = 0.019). The response accuracy was not significantly different between before and after exercise in both conditions, which indicated that the response accuracy was controlled as intended. The levels of plasma norepinephrine and adrenocorticotropic hormone were significantly increased after exercise (P < 0.05). These results demonstrated that the reaction time in the incongruent condition increased after sustained high-intensity exercise with a cognitive function test with the response accuracy controlled, indicating a decline in executive function. Increased levels of plasma norepinephrine and adrenocorticotropic hormone may contribute, at least in part, to such decline in executive function.

Influence of different load exercise to muscle activity during subsequent exercise with 75% of one repetition maximum (RM) load among trained and untrained individuals was verified. Resistance-trained men who were involved in resistance training (n = 16) and healthy young men who did not exercise regularly (n = 16) were recruited for this study. Each subject performed bench pressing with a narrow grip exercise using two different training set methods, the drop-set (DS) (3 sets × 2-10 repetitions with 95-75% of 1RM) and the reverse drop-set (RDS) (3 sets × 3-10 repetitions with 55-75% of 1RM). The mean concentric contraction power, root mean square (RMS) of electromyography (EMG), area under the oxygenated hemoglobin (Oxy-Hb) curve, and time constant for muscle oxygen consumption (TcVO2mus) values of the triceps brachii were measured during and after the DS and RDS. The trained group demonstrated significantly higher mean muscle power (242.9 ± 39.6 W vs. 215.8 ± 31.7 W), RMS of EMG (86.4 ± 10.4 % vs. 68.3 ± 9.6 %), and area under the Oxy-Hb curve (38.6 ± 7.4 %• sec vs. 29.3 ± 5.8 %• sec) values during the DS than during the RDS (p < 0.05). However, in the untrained group none of the parameters differed significantly for both the DS and RDS. Furthermore, a negative correlation was detected between the area under the Oxy-Hb curve and muscle thickness (r = -0.51, p < 0.01). Long-term effects of DS on muscle strengthening and hypertrophy will be explored in further research.

High whole-body and visceral adiposity are risk factors that can cause metabolic diseases. We hypothesized that the total hemoglobin concentration (total-Hb) in abdominal subcutaneous adipose tissue (SATab), an indicator of white adipose tissue (WAT) vascularity, correlates negatively with risk factors for developing metabolic diseases, such as whole-body and visceral adiposity. We tested the optical characteristics of abdominal tissue in 140 participants (45 men and 95 women) who were apparently healthy individuals with a median age of 39 years. They also had a median body fat percentage of 25.4%, a visceral fat area of 50.4 cm2, and a SATab thickness of 1.05 cm. These tests were conducted using near-infrared time-resolved spectroscopy (NIRTRS) with a 2-cm optode separation. To distinguish the segments of SATab (SegSAT) and the mixture of muscle and SATab (SegSAT+Mus), the threshold was analyzed using the slopes of (total-Hb) against the thickness of SATab using the least-squares mean method. According to the results from the logistic regression analysis, the percentage of body fat and visceral fat area remained significant predictors of the (total-Hb) (p = 0.005 and p = 0.043, respectively) in the data for SegSAT (no influence from the SATab thickness). We conclude that simple, rapid, and noninvasive NIRTRS-determined (total-Hb) in WAT could be a useful parameter for evaluating risk factors for metabolic diseases.

Introduction: A physically active lifestyle leads to reduced risks of cardiovascular disease events in the elderly. A level of circulating salusin-α is a novel biomarker of cardiovascular disease and is associated with increased arterial stiffness. Indeed, circulating levels of salusin-α are lower in patients with coronary arterial disease and hypertension compared to healthy subjects. However, it is unknown whether circulating salusin-α levels are decreased with advanced age and whether circulating salusin-α levels are associated with the reduced cardiovascular disease risks by exercise lifestyle. Hypothesis: We assessed the hypothesis that salusin-α is involved to the changes in cardiovascular disease risk by aging or exercise-promoting healthy lifestyle. Methods: In Experiment 1, 105 healthy subjects (20-80 years old) participated in a cross-sectional study. The subjects were divided into 2 groups: young (under 40 years, n=45) versus middle-age and older (over 40 years, n=60). In Experiment 2, 36 young subjects (young aerobic exercise training group; Young-AT: n=27 and control group; Young-Con: n=9) and 40 healthy middle-age and older subjects (middle-age and older aerobic exercise training group; Middle-age and older-AT: n=26 and control group; Middle-age and older-Con: n=14) volunteered to participate. Subjects in AT groups completed eight weeks of habitual aerobic exercise (60-70% peak oxygen uptake [VO2peak] for 45 min, 3 days/week). We measured serum salusin-α level, carotid-femoral pulse wave velocity (cfPWV), brachial artery systolic (SBP) and diastolic (DBP) blood pressures, common carotid intima-media thickness (ccIMT) and VO2peak. Results: In the cross-sectional study, cfPWV, SBP, DBP and ccIMT were significantly higher and serum salusin-α levels were significantly lower in the middle-age and older adults compared to young adults. Negative correlations were observed between serum salusin-α levels and age (r=–0.698, P Conclusions: Changes in salusin-α levels may be a novel biomarker of the increase in cardiovascular disease risks with age and the decrease in cardiovascular disease risks with exercise lifestyle in healthy middle-age and older adults.

Introduction: Habitual aerobic exercise leads to reduction of arterial wall thickness and arterial stiffness with aging. Recently, C1q has been identified as a novel myokine, and the expression of muscle C1q mRNA increases with aging. Additionally, in vivo and in vitro studies, C1q induces proliferation of vascular smooth muscle cells. However, it remains unclear whether the secretion of myokines, C1q, TNF-alpha and IL-6 are related to the changes in cardiovascular disease risk by aging and regular exercise. PURPOSE: This study aimed to clarify whether serum C1q, TNF-alpha and IL-6 levels are associated with the changes in cardiovascular disease risks with aging and regular aerobic exercise. Methods: In a cross-sectional study, 127 healthy male and female subjects (18-81 years) were enrolled in this study. Subjects were divided into two groups; young ( Results: In the cross-sectional study, serum C1q, TNF-alpha and IL-6 levels, cfPWV and ccIMT were significantly higher in middle-aged and older group as compared with young group (respectively p Conclusion: These results suggest that circulating C1q level may reflect the changes of arterial stiffness and thickness with aging and regular exercise, and the reduction of serum C1q level in response to regular aerobic exercise may contribute to the reduction in cardiovascular disease risks in the elderly.

High-intensity intermittent exercise training (HIIT) has been proposed as an effective approach for improving both, the aerobic and anaerobic exercise capacity. However, the detailed molecular response of the skeletal muscle to HIIT remains unknown. We examined the effects of the HIIT on the global gene expression in the human skeletal muscle. Eleven young healthy men participated in the study and completed a 6-week HIIT program involving exhaustive 6–7 sets of 20-s cycling periods with 10-s rests. In addition to determining the maximal oxygen uptake ($${\dot{{\rm{V}}}{\rm{O}}}_{2{\rm{\max }}}$$ V ˙ O 2 max ), maximal accumulated oxygen deficit, and thigh muscle cross-sectional area (CSA), muscle biopsy samples were obtained from the vastus lateralis before and after the training to analyse the skeletal muscle transcriptome. The HIIT program significantly increased the $${\dot{{\rm{V}}}{\rm{O}}}_{2{\rm{\max }}}$$ V ˙ O 2 max , maximal accumulated oxygen deficit, and thigh muscle CSA. The expression of 79 genes was significantly elevated (fold-change >1.2), and that of 73 genes was significantly reduced (fold-change

The accumulation of intramyocellular lipid (IMCL) and extramyocellular lipid (EMCL) is associated with arterial stiffness in middle-aged and older adults. Habitual aerobic exercise induces the improvement of arterial stiffness with reduction in fat accumulation. However, the relationship between aerobic exercise-induced changes in muscular lipids and arterial stiffness remains unclear. The purpose of this study was to investigate whether habitual aerobic exercise-induced changes in IMCL and EMCL content would lead to an improvement of arterial stiffness. First, in a cross-sectional study, we investigated whether cardiorespiratory fitness level affects the association between IMCL or EMCL content and arterial stiffness in 60 middle-aged and older subjects (61.0±1.3 years). Second, in an intervention study, we examined whether aerobic exercise training-induced changes in IMCL and EMCL content are associated with a reduction in arterial stiffness in 18 middle-aged and older subjects (67.0±1.7 years). In the cross-sectional study, IMCL content was negatively correlated with brachial-ankle pulse wave velocity (baPWV) (r=-0.47, P