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Background This study investigated the relationship between long-term body weight gain after maturity and the incidence of chronic kidney disease (CKD). Methods The participants were 303 men without a history of cardiovascular and cerebrovascular diseases, kidney dysfunction, or dialysis treatment. Their body weight gain after maturity was examined using a standardized self-administered questionnaire. The participants were divided into two groups based on the presence/absence of a body weight gain of ≥10 kg since 20 years of age. Results After a 6-year follow-up, the cumulative incidence of CKD was significantly higher in participants with a body weight gain of ≥10 kg than in participants without body weight a body weight gain of ≥10 kg since 20 years of age (log-rank test: P = 0.041). After adjusting for the age, body mass index, estimated glomerular filtration rate levels, smoking and drinking habits, and the presence of hypertension, dyslipidemia, and hyperglycemia at baseline, the normal body weight participants with a body weight gain of ≥10 kg since 20 years of age was significantly related to the incidence of CKD (hazard ratio 2.47; 95% confidence of interval, 1.02-6.01, P = 0.045). Conclusions These results suggest that long-term body weight gain after maturity in normal body weight participants may be associated with the incidence of CKD, independent of current body weight.

We investigated factors correlated with cognitive decline in elderly adults by measuring aerobic fitness, physical activity, and cognitive function. Participants were community-dwelling adults aged 65 years or older (N = 455; 130 men and 325 women). Aerobic fitness was assessed in an incremental exercise test using a cycle ergometer; physical activity was determined with step counts using a uniaxial accelerometer. Cognitive function was examined using Urakami’s screening test for Alzheimer’s disease (AD). We analyzed the results for 287 participants (71 men and 216 women) with no missing data. The maximum possible score for cognitive function was 15; impairment was defined as scores of ≤ 12. The χ2 and t-test were used to compare data between participants with impairment and controls. Male and female participants were analyzed separately. After adjusting for age, BMI, and diabetes, we performed analysis of covariance. Of the total, 29 participants (10.1%) were categorized as impaired on screening. For aerobic fitness and physical activity, there were no significant differences between men with impairment and controls. However, aerobic fitness was significantly lower (p < 0.002) and physical activity was not significantly different for women with impairment than for controls by t-test. After adjustment, significant differences were also found for aerobic fitness (p < 0.001) between the groups in women. The impairment group had a significantly higher ratio of women with diabetes than the control group (p < 0.05). Our results suggest that decline in aerobic fitness is obviously associated with decline in cognitive function among women.

AIM This study investigated whether driving-related anxiety was independently associated with physical parameters and physical function in community-dwelling older people. METHODS Participants were 523 community-dwelling older drivers (353 men and 170 women). Participants self-reported driving-related anxiety when driving in familiar environments, and completed physical assessments: visual impairment, auditory impairment, cerebrovascular disease (CVD), hand grip strength, knee extension strength, timed up and go (TUG), chair stand, one leg standing with open eyes, functional reach, vertical jump, preferred gait speed and maximal gait speed. Participants were divided into a driving-related anxiety group (72.8±5.1 years; 21 men, seven women) and a no-anxiety (non-anxiety) group (70.7±4.7 years; 325 men, 163 women). We examined physical performance differences between the anxiety and non-anxiety groups using analysis of covariance, and investigated the relationship between anxiety, physical function and performance using logistic regression analysis (forward stepwise selection). RESULTS The driving-related anxiety group was significantly older, with higher rates of visual impairment, auditory impairment, and CVD than the non-anxiety group. The anxiety group exhibited independently poorer TUG and maximal gait speed (P

Genetic polymorphisms and sex differences are suggested to affect muscle fiber composition; however, no study has investigated the effects of genetic polymorphisms on muscle fiber composition with respect to sex differences. Therefore, the present study examined the effects of genetic polymorphisms on muscle fiber composition with respect to sex differences in the Japanese population. The present study included 211 healthy Japanese individuals (102 men and 109 women). Muscle biopsies were obtained from the vastus lateralis to determine the proportion of myosin heavy chain (MHC) isoforms (MHC-I, MHC-IIa, and MHC-IIx). Moreover, we analyzed polymorphisms in α-actinin-3 gene ( ACTN3; rs1815739 ), angiotensin-converting enzyme gene ( ACE; rs4341 ), hypoxia-inducible factor 1 α gene ( rs11549465 ), vascular endothelial growth factor receptor 2 gene ( rs1870377 ), and angiotensin II receptor, type 2 gene ( rs11091046 ), by TaqMan single-nucleotide polymorphism genotyping assays. The proportion of MHC-I was 9.8% lower in men than in women, whereas the proportion of MHC-IIa and MHC-IIx was higher in men than in women (5.0 and 4.6%, respectively). Men with the ACTN3 RR + RX genotype had a 4.8% higher proportion of MHC-IIx than those with the ACTN3 XX genotype. Moreover, men with the ACE ID + DD genotype had a 4.7% higher proportion of MHC-I than those with the ACE II genotype. Furthermore, a combined genotype of ACTN3 R577X and ACE insertion/deletion (I/D) was significantly correlated with the proportion of MHC-I ( r = −0.23) and MHC-IIx ( r = 0.27) in men. In contrast, no significant correlation was observed between the examined polymorphisms and muscle fiber composition in women. These results suggest that the ACTN3 R577X and ACE I/D polymorphisms independently affect the proportion of human skeletal muscle fibers MHC-I and MHC-IIx in men but not in women.NEW & NOTEWORTHY In men, the RR + RX genotype of the α-actinin-3 gene ( ACTN3) R577X polymorphism was associated with a higher proportion of myosin heavy chain (MHC)-IIx. The ID + DD genotype of the angiotensin-converting enzyme gene ( ACE) insertion/deletion (I/D) polymorphism, in contrast to a previous finding, was associated with a higher proportion of MHC-I in men. In addition, the combined genotype of these polymorphisms was correlated with the proportion of MHC-I and MHC-IIx in men. Thus ACTN3 R577X and ACE I/D polymorphisms influence the muscle fiber composition in Japanese men.

Background This retrospective study evaluated the influence of the joint impact of habitual exercise and glycemic control on the incidence of chronic kidney disease (CKD) during a 6-year follow-up period in middle-aged and older males. Methods The study population included 303 males without a history of cardiovascular disease, stroke, renal dysfunction, or dialysis treatment. Their lifestyle behaviors regarding exercise and physical activity were evaluated using a standardized self-administered questionnaire. The participants were divided into four categories according to the performance or non-performance of habitual exercise and the presence or absence of hyperglycemia. Results After 6 years, 32 subjects (10.6%) developed CKD (estimated glomerular filtration rate

We developed a short-interval, low-intensity, slow-jogging (SJ) program consisting of sets of 1 min of SJ at walking speed and 1 min of walking. We aimed to examine the effects of an easily performed SJ program on skeletal muscle, fat infiltration, and fitness in older adults.A total of 81 community-dwelling, independent, older adults (70.8 ± 4.0 years) were randomly assigned to the SJ or control group. The SJ group participants were encouraged to perform 90 min of SJ at their anaerobic threshold (AT) intensity and 90 min of walking intermittently per week. Aerobic capacity at the AT and sit-to-stand (STS) scores were measured. Intracellular water (ICW) in the legs was assessed by segmental multi-frequency bioelectrical impedance analysis. Subcutaneous (SAT) and intermuscular (IMAT) adipose tissue and muscle cross-sectional area (CSA) were measured at the mid-thigh using computed tomography.A total of 75 participants (37 SJ group, 38 controls) completed the 12-week intervention. The AT and STS improved in the SJ group compared with the controls (AT 15.7 vs. 4.9 %, p 0.01; STS 12.9 vs. 4.5 %, p 0.05). ICW in the upper leg increased only in the SJ group (9.7 %, p 0.05). SAT and IMAT were significantly decreased only in the SJ group (p 0.01).The 12-week SJ program was easily performed by older adults with low skeletal muscle mass, improved aerobic capacity, muscle function, and muscle composition in older adults.

It has been suggested that breakfast omission, as opposed to breakfast consumption, has the detrimental effects on cognitive function. However, the effects of acute exercise following breakfast omission on cognitive function are poorly understood, particularly during exercise. The purpose of this study was to examine the interactive effects of breakfast and exercise on cognitive function. Ten participants completed cognitive tasks at rest and during exercise in the breakfast consumption or omission conditions. Blood glucose concentration was measured immediately after each cognitive task. We used cognitive tasks to assess working memory [Spatial Delayed Response (DR) task] and executive function [Go/No-Go (GNG) task]. The participants cycled ergometer for 30 min while keeping their heart rate at 140 beats·min(-1). Accuracy of the GNG task was lower at rest in the breakfast omission condition than that in the breakfast consumption condition (Go trial: P=0.012; No-Go trial: P=0.028). However, exercise improved accuracy of the Go trial in the breakfast omission condition (P=0.013). Reaction time in the Go trial decreased during exercise relative to rest in both conditions (P=0.002), and the degree of decreases in reaction time was not different between conditions (P=0.448). Exercise and breakfast did not affect the accuracy of the Spatial DR task. The present results indicate that breakfast omission impairs executive function, but acute exercise improved executive function even after breakfast omission. It appears that beneficial effects of acute exercise on cognitive function are intact following breakfast omission.

This study was retrospectively designed to evaluate the influence of healthy lifestyle behaviors on the incidence of chronic kidney disease (CKD) during a 5-year follow-up period in middle-aged and older males. The subjects included 252 males without a history of cardiovascular disease, stroke, renal dysfunction and/or dialysis treatment who were not taking any medications. Their lifestyle behaviors were evaluated using a standardized self-administered questionnaire and defined as follows: (1) habitual moderate exercise, (2) daily physical activity, (3) fast walking speed, (4) slow eating speed, (5) no late-night dinner, (6) no bedtime snacking and (7) no skipping breakfast. The participants were divided into four categories, which were classified into quartile distributions according to the number of healthy lifestyle behaviors (7–6, 5, 4 and ≤3 groups). After 5 years, the incidence of CKD [estimated glomerular filtration rate (eGFR)

Background: This cross-sectional study evaluated the association between unhealthy lifestyle behaviors and the prevalence of chronic kidney disease (CKD) in middle-aged and older men. Methods: The subjects included 445 men without a history of cardiovascular disease, stroke, or dialysis treatment, who were not taking medications. Unhealthy lifestyle behaviors were evaluated using a standardized selfadministered questionnaire and were defined as follows: 1) lack of habitual moderate exercise, 2) lack of daily physical activity, 3) slow walking speed, 4) fast eating speed, 5) late-night dinner, 6) bedtime snacking, and 7) skipping breakfast. The participants were divided into four categories, which were classified into quartile distributions based on the number of unhealthy lifestyle behaviors (0–1, 2, 3, and ≥4 unhealthy behaviors). Results: According to a multivariate analysis, the odds ratio (OR) for CKD (defined as estimated glomerular filtration rate [eGFR]

It has been suggested that acute exercise improves cognitive function. However, little is known about how exercise under hypoxia affects cognitive function. The purpose of this study was to determine if hypoxia alters working memory and executive function during prolonged exercise. Sixteen participants performed cognitive tasks at rest and during exercise under normoxia and hypoxia [fraction of inspired oxygen (FIO2) = 0.15, corresponding to an altitude of approximately 2600 m]. The level of hypoxia was moderate. We used a combination of Spatial Delayed Response (Spatial DR) task and Go/No-Go (GNG) task, where spatial working memory and executive function are required. Working memory was assessed by the accuracy of the Spatial DR task, and executive function was assessed by the accuracy and reaction time in the GNG task. The participants cycled an ergometer for 30 min under normoxia and moderate hypoxia while keeping their heart rate (HR) at 140 beats/min. They performed the cognitive tasks 5 min and 23 min after their HR reached 140 beats/min. Moderate hypoxia did not alter the accuracy of the Spatial DR (P = 0.38) and GNG tasks (P = 0.14). In contrast, reaction time in the GNG task significantly decreased during exercise relative to rest under normoxia and moderate hypoxia (P = 0.02). These results suggest that moderate hypoxia and resultant biological processes did not provide sufficient stress to impair working memory and executive function during prolonged exercise. The beneficial effects on speed of response appear to persist during prolonged exercise under moderate hypoxia.

It is well known that imbalances in the dietary electrolytes are associated with a significantly higher incidence of cardiovascular disease (CVD). On the other hand, a prolonged heart rate corrected-QT (QTc) interval is associated with an increased risk of cardiac autonomic nervous system dysfunction, the incidence of CVD and sudden cardiac death. This study was designed to clarify the association between the nutritional status and the QTc interval in elderly subjects. The subjects included 119 elderly subjects (46 males and 73 females, age; 72.9±4.8 y) without a history of CVD, who were taking cardioactive drugs. Resting 12-lead electrocardiography was performed, while the QTc interval was calculated according to Bazett's formula. The nutritional status was assessed using a brief self-administered diet history questionnaire. The subjects were divided into three categories, which were defined as equally trisected distributions of the body mass index (BMI). The QTc interval was significantly longer in both the low and high BMI groups than in the moderate BMI group in both genders (p

This study examined (1) the effects of a single bout of exercise at different pedaling rates on physiological responses, pedal force, and muscle oxygenation, and (2) the effects of 2 weeks of training with different pedaling rates on work rate at lactate threshold (WorkLT). Sixteen healthy men participated in the study. An incremental exercise test involving pedaling a cycling ergometer at 50 rpm was conducted to assess maximal oxygen consumption and WorkLT. The participants performed constant workload, submaximal exercise tests at WorkLT intensity with three different pedaling rates (35, 50, and 75 rpm). Oxygen consumption ( $$\dot{V}$$ O2), blood pressure, heart rate (HR), blood lactate, and pedal force were measured and oxy-hemoglobin/myoglobin concentration (OxyHb/Mb) at vastus lateralis was monitored by near-infrared spectroscopy during exercise. The participants were then randomly assigned to cycling exercise training at WorkLT in either the low or high frequency pedaling rate (LFTr, 35 rpm or HFTr, 75 rpm) group. Each 60-min training session was performed five times/week. Despite maintaining the same work rate, $$\dot{V}$$ O2 and HR were significantly lower at 35 than 75 rpm. Conversely, integrated pedal force was significantly higher at 35 than 75 rpm. Peripheral OxyHb/Mb was significantly lower at 35 than 75 rpm. After 2 weeks of training, WorkLT normalized to body mass significantly increased in the LFTr, but not the HFTr group. Pedaling rate and the corresponding pedal force and peripheral oxygenation during cycling exercise influence the effect of training at LT on WorkLT.

Aim Increased physical activity can reduce the incidence of cardiovascular disease and the mortality rate. In contrast, a prolonged heart rate corrected-QT (QTc) interval is associated with an increased risk of arrhythmias, sudden cardiac death and coronary artery disease. The present cross-sectional study was designed to clarify the association between the physical activity level and the QTc interval in older adults. Methods The participants included 586 older adults (267 men and 319 women, age 71.2 ± 4.7 years) without a history of cardiovascular disease, who were taking cardioactive drugs. Electrocardiography was recorded with a standard resting 12-lead electrocardiograph, while the QTc interval was calculated according to Hodges' formula. The physical activity level was assessed using a triaxial accelerometer. The participants were divided into four categories, which were defined equally quartile distributions of the QTc interval. Results After adjusting for age, body mass index, waist circumference and the number of steps, the time spent in inactivity was higher and the time spent in light physical activity was significantly lower in the longest QTc interval group than in the shortest QTc interval group in both sexes (P

Respiratory gas collection and analysis with indirect calorimetry allows assessment of energy and substrate use during rest and exercise and aerobic capacity. We have developed a novel system for simultaneous multiple-subject measurement of respiratory gas exchange during rest and exercise for up to five subjects, and validated the system with a series of experiments. Thirteen healthy young men (mean age 22 ± 2 years, height 172 ± 6 cm, weight 67.1 ± 11.6 kg) participated in this study. Memory problems of the mass spectrometer, which are caused by switching analyzed gases of different compositions between channels, was sufficiently eliminated with a washout of 2 s (seconds) with errors of less than 0.3% for O2 and less than 0.4% for CO2. The high-response mass spectrometer and specially designed mixing chamber enabled correct estimation of metabolic measurements, even for gas concentration data from a non-continuous flow of any given 1s of every 10-s interval (spot-sampling method). Diet-induced thermogenesis (DIT) and oxygen consumption (VO2) during maximal incremental exercise were not significantly different between the novel and Douglas bag methods (P = 0.61 and P = 0.56, respectively). The limit of agreement of DIT and VO2 during maximal incremental exercise between the two methods were 2.8 ± 43.6% and 0.9 ± 4.8%, respectively. We concluded that the newly developed system has reasonable validity over a wide range.

This cross-sectional study was performed to determine the relationship between the intensity of daily physical activity (PA) assessed by triaxial accelerometer (ACCtri) and muscle strength or gait speed. We measured the hand grip strength (HGS) and knee extension strength (KES) as well as preferred gait speed (PGS) and maximal gait speed (MGS) of a total of 178 community-dwelling elderly men aged 70-79 years. The duration and intensity of PA were evaluated by ACCtri on eight consecutive days, and the total duration of each level of activity intensity (Inactivity, Light PA: LPA, Moderate PA: MPA, and Vigorous PA: VPA) and daily step count were also measured. After adjustment for age, body mass index (BMI) and body fat percentage, KES and MGS were significantly correlated with step count. The duration of MPA was correlated with KES (r = 0.208, P < 0.01) and MGS (r = 0.213, P < 0.05). PGS and HGS were not significantly correlated with any PA parameters. MPA and step counts were significantly, but weakly, related to KES and MGS. The results suggest that a longer time spent on either daily ambulatory activity or MPA may be associated with age-associated loss of muscle strength (dynapenia) and gait decline in older men.

Objective: To evaluate the effects of energy restriction with or without aerobic exercise on thigh muscle mass and quality in adults with visceral adiposity. Methods: 75 males and females were randomly assigned to the groups ‘diet only' (DO; n = 42) or ‘diet plus aerobic exercise' (D/Ex; n = 33) for 12 weeks. The target energy intake in both groups was 25 kcal/kg of ideal body weight. Subjects in the D/Ex group were instructed to exercise for ≥300 min/week at lactate threshold. Computed tomography was used to measure thigh muscle cross-sectional area (CSA), normal-density muscle area (NDMA), and visceral fat area. Results: Total body weight (DO: -6.6 ± 3.6%; D/Ex: -7.3 ± 4.6%) and visceral fat (DO: -16.0 ± 13.8%; D/Ex: -23.1 ± 14.7%) decreased significantly in both groups; however, the changes were not significantly different between the two groups. The decrease in muscle CSA was significantly greater in the DO group (-5.1 ± 4.5%) compared with the D/Ex group (-2.5 ± 5.0%). NDMA decreased significantly in the DO (-4.9 ± 4.9%) but not in the D/Ex group (-1.4 ± 5.0%). Conclusion: Aerobic exercise attenuated the loss of skeletal muscle during energy restriction in adults with visceral adiposity.

Rodent study suggests that interleukin (IL)-15 administration enhances insulin sensitivity. Although it is well known that circulating levels of typical inflammatory markers (C-reactive protein [CRP] and IL-6) are positively associated with homeostasis model assessment-insulin resistance (HOMA-IR), there are no studies investigating the associations of other inflammatory markers including IL-15 with peripheral/hepatic insulin sensitivity in humans. The current study aimed to examine the relationship between the levels of adiopokines or inflammatory cytokines and insulin sensitivity in 8 healthy middle-aged men. Circulating levels of 10 insulin sensitizing adipokines or inflammatory cytokines (total adiponectin [APN], high molecular weight adiponectin [HMW-APN], IL-4, IL-5, IL-6, IL-8, IL-15, interferon [IFN]-γ, tumor necrosis factor [TNF]-α, and TNF-β) were measured. A stable-labeled frequently sampled intravenous glucose tolerance test was performed to assess peripheral () and hepatic () insulin sensitivity estimated by 2-compartment minimal model. The levels of 3 inflammatory cytokines (IL-4, IL-6, and IL-15) were significantly and inversely correlated with either and . The association between IL-15 and either or was significant even after adjusting for age and percent body fat (p

Background: The double product (DP) breakpoint of heart rate (HR) and systolic blood pressure has been identified as coincident with anaerobic threshold (AT), but there are no simple methods for measuring cardiac metabolic stress (CMS) during an exercise test. It was hypothesized that the DP of HR and the amplitude of the first heart sound (AHS1) (DP-AHS1) would reflect CMS, and thus, the breakpoint in the DP-AHS1 (DPBP-AHS1) could be an alternative method for determining AT. Methods and Results: Subjects (age range, 18–73 years) were recruited to perform a graded exercise test on a cycle ergometer with continuous monitoring of DP-AHS1, with left ventricular pressure (LVP; experiment 1, Ex1), plasma catecholamine and blood lactate (experiment 2, Ex2) and gas exchange (experiment 3, Ex3). Ex1: in all subjects there was a strong correlation between AHS1 and LVdP/dtmax (r=0.94–0.98), and between the DP-AHS1 and the triple product of HR, LVdP/dtmax, and max LVP (r=0.98–0.99). Ex2: DP-AHS1 was strongly correlated with adrenaline (r=0.97–1.00) and lactate (r=0.96–1.00) levels in all subjects. Ex3: there was a strong correlation between DPBP-AHS1, AT and maximum oxygen consumption. Conclusions: The present simple measure of DP-AHS1 can reflect plasma adrenaline and lactate levels during graded exercise testing. Further, DPBP-AHS1 is a surrogate marker of AT and a good index of functional aerobic capacity. (Circ J 2013; 77: 2736–2741)

Muscle peroxisome proliferator-activated receptor gamma co-activator 1 (PGC-1)α gene expression is influenced by the Gly482Ser gene polymorphism, which is a candidate genetic risk factor for diabetes mellitus and obesity. This study investigated the effects of PGC-1 gene Gly482Ser polymorphisms on alterations in glucose and lipid metabolism induced by exercise training. A 12-week intervention study was performed for 119 participants who were more than 65 years of age and completed exercise training at lactate threshold intensity. Total cholesterol and low-density lipoprotein cholesterol were significantly reduced in Gly/Gly but not in Gly/Ser and Ser/Ser participants after exercise. The Gly/Gly genotype of the PGC-1 gene Gly482Ser polymorphism influences the effects of moderate-intensity exercise training on low-density lipoprotein cholesterol and total cholesterol concentrations in older people.

This study aimed to ascertain if performance on the Timed Up and Go (TUG) test is associated with indicators of brain volume and cognitive functions among community-dwelling older adults with normal cognition or mild cognitive impairment.Participants were 80 community-dwelling older adults aged 65-89years (44 men, 36 women), including 20 with mild cognitive impairment. Participants completed the TUG and a battery of cognitive assessments, including the Mini-Mental State Examination (MMSE), the Logical Memory I and II (LM-I, LM-II) subtests of the Wechsler Memory Scale-Revised; and the Trail Making Test A and B (TMT-A, TMT-B). Bilateral, right- and left-side medial temporal area atrophy as well as whole gray and white matter indices were determined with the Voxel-based Specific Regional Analysis System for Alzheimer's Disease. We divided participants into three groups based on TUG performance: "better" (≤6.9s); "normal" (7-10s); and "poor" (≥10.1s).Worse TMT-A and TMT-B performance showed significant independent associations with worse TUG performance (P0.05, P0.01 for trend, respectively). After adjusting for covariates, severe atrophy of bilateral, right-, and left-side medial temporal areas were significantly independently associated with worse TUG performance (P0.05 for trend). However, no significant associations were found between MMSE, LM-I, LM-II, whole gray and white matter indices, and TUG performance.Worse TUG performance is related to poor performance on TMT-A and TMT-B, and is independently associated with severe medial temporal area atrophy in community-dwelling older adults.

Previous studies have shown that an enriched environment (EE) has an important effect on brain function via the neuronal nitric oxide synthase/nitric oxide (nNOS/NO) pathway in young and aged animals. However, whether EE induces its effect by altering nNOS expression levels and whether it lowers anxiety-like behaviors in aged mice remains unclear. Here, we show that nNOS expression levels increased with age in the hippocampus and cerebellum in aged mice, but not in the cortex. Moreover, EE reduced anxiety-like behaviors in aged mice and reduced nNOS expression levels in the cerebellum, but not in the cortex. The present study suggests that EE improves anxiety-like behaviors in aged mice by altering nNOS expression levels in the hippocampus or cerebellum.

Recently, we proposed that strenuous exercise impairs peripheral visual perception because visual responses to peripheral visual stimuli were slowed during strenuous exercise. However, this proposal was challenged because strenuous exercise is also likely to affect the brain network underlying motor responses. The purpose of the current study was to resolve this issue. Fourteen participants performed a visual reaction-time (RT) task at rest and while exercising at 50% (moderate) and 75% (strenuous) peak oxygen uptake. Visual stimuli were randomly presented at different distances from fixation in two task conditions: the Central condition (2° or 5° from fixation) and the Peripheral condition (30° or 50° from fixation). We defined premotor time as the time between stimulus onset and the motor response, as determined using electromyographic recordings. In the Central condition, premotor time did not change during moderate (167 ± 19 ms) and strenuous (168 ± 24 ms) exercise from that at rest (164 ± 17 ms). In the Peripheral condition, premotor time significantly increased during moderate (181 ± 18 ms, P < 0.05) and strenuous exercise (189 ± 23 ms, P < 0.001) from that at rest (173 ± 17 ms). These results suggest that increases in Premotor Time to the peripheral visual stimuli did not result from an impaired motor-response network, but rather from impaired peripheral visual perception. We conclude that slowed response to peripheral visual stimuli during strenuous exercise primarily results from impaired visual perception of the periphery.

Several metabolic gene expressions are regulated in concert with muscle glycogen status. We hypothesized that intermittent exercise performed at high but sub-maximal intensities with long recovery periods would induce a low glycogen state that would stimul- ate peroxisome proliferator-activated receptor-γ coa- ctivator-1α (PGC1-α) and pyruvate dehydrogenase kinase-4 (PDK-4) gene expression in muscle. Nine young human subjects performed two intermittent exercise sessions. One session consisted of 60 s cycling bouts at VO2max (IE100%), and the other session consisted of 75 s cycling bouts at 80% VO2max (IE80%). Twelve bouts of exercise were completed in both sessions with a 4 min rest between each bout. Muscle specimens were obtained at pre-exercise and immediately, 1.5 h and 3 h post-exercise. Muscle gly- cogen was significantly decreased after both sessions (IE100%, 94.1 ± 5.8 to 38.7 ± 5.5 mmol/kg w.w.; IE80%, 94.6 ± 9.1 to 53.3 ± 4.8 mmol/kg w.w.; both P α and PDK- 4 mRNA expression were significantly increased after exercise in both IE100% and IE80% (PGC-1α: ~3.7 and ~2.9-fold, respectively; PDK-4: ~11.1 and ~3.5-fold, respectively; all P 100% than in IE80% (P a and PDK-4 mRNA expression, suggesting that increasing exercise intensity contributes to muscle glycogen depletion and PDK-4 mRNA expression in human skeletal muscle.

The relationship between minute-by-minute stepping rate under free-living and obesity remains unclear. The purpose of the present investigation was to compare the levels of physical activity (PA) based on the minute-by-minute stepping rate under free-living conditions between normal weight (NW) and overweight and obese (OV) individuals. A total 40 volunteers participated in the present investigation. These participants were divided into NW or OV according to the body mass index (25 kg m(-2) or 25 kg m(-2)). All participants wore a pedometer with a uni-axial accelerometer (Lifecorder-EX 4sec, Kenz, Japan) for 7 days continuously. The Lifecorder determined the number of steps and time spent in PA at100, 100-129, 130 steps min(-1) according to the minute-by-minute stepping rate. The OV group took a significantly fewer number of steps per day in comparison to that in the NW group (p0.05). The average daily stepping rate was significantly lower in the OV group in comparison to that in the NW group (p = 0.01). Furthermore, the OV group spent a significantly shorter time in PA at a 100 steps min(-1) of the stepping rate compared with that in the NW group (p0.05). These results indicate that obese individuals spent significantly shorter time in PA at 100 steps min(-1) of stepping rate in comparison to the NW individuals.

This study sought to determine whether aerobic exercise training affects cognitive functioning among semi-independent (> 75 years) and independent elderly people. Seventysix semi-independent and independent elderly subjects were divided into the following groups: semi-independent control (n = 16); semi-independent training (n = 13); independent control (n = 22); independent training (n = 25). During the 12-week intervention, subjects in both training groups performed a bench-stepping exercise at the intensity of the lactate threshold. Subjects were assessed at baseline and post-intervention using the Frontal Assessment Battery test (FAB), the Modified Mini-Mental State Exam (3MS), and a bench-stepping test of aerobic capacity. During the intervention, FAB scores improved only in the semi-independent training group (p = .002), while 3MS and MMSE scores improved in both the semi-independent training (p = .032 and p = .004) and independent training groups (p = .001 and p = .013). FAB and 3MS scores were higher in the semi-independent training (p = .001 and p = .002) compared with the semi-independent control group after the intervention. Finally, post-intervention scores for FAB, and 3MS in the semi-independent training group almost reached the baseline levels of the independent control and independent training groups. These results indicate that moderate intensity bench-stepping exercise training can improve cognitive and frontal lobe functioning in semi-independent elderly people, almost to the level exhibited by independent elderly people. (Jpn. J. Phys. Fitness Sports Med., 60(4): 379〜386(2011))

Background: We examined the long-term effects of home-based bench-stepping exercise training on total healthcare expenditure (TOHEX) and number of outpatient visits (NOVIS) in elderly adults.Methods: A total of 189 elderly Japanese (age 73 ± 4 years) participated in this study. They were randomly assigned to either an exercise or control group. TOHEX, NOVIS, and outpatient expenditure (OPEX) were evaluated every 6 months from 1 year before the start to the end of the intervention period, as well as 1 year after the end of the intervention. The exercise group was encouraged to perform home-based bench-stepping exercise training on most, and preferably all, days of the week for 18 months.Results: The exercise group showed significant increases in lactate threshold as compared with pre-intervention values. There were no significant differences in TOHEX, OPEX, or NOVIS between the exercise and control groups 1 year before the start of the intervention, and the values remained similar during the first 12 months of the intervention period. However, at 18 months, TOHEX, NOVIS, and OPEX were significantly lower in the exercise group than in the control group (TOHEX: 170 007 ± 192 072 vs. 294 705 ± 432 314 yen, P = 0.008; NOVIS: 19.2 ± 26.3 vs. 28.2 ± 32.1 days, P = 0.012; OPEX: 132 973 ± 132 016 vs. 187 799 ± 158 167 yen, P = 0.005).Conclusions: The data indicate that a long-term home-based bench-stepping exercise program can reduce healthcare expenditure in elderly Japanese.

We investigated the association between the angiotensin I-converting enzyme (ACE) gene insertion (I)/deletion (D) polymorphism and endurance running performance in Japanese elite runners, including several Olympic athletes. The frequency of the I/I genotype was not significantly higher and the frequency of the D/D genotype was not significantly lower in elite runners compared with non-athletes. However, the frequency of the I/D genotype tended to be lower in elite runners than in non-athletes. The best performance was significantly higher for runners with the D/D genotype than for those with the I/I genotype, and the average running speed was significantly higher for those with the combined D/D + I/D genotypes than for those with the I/I genotype. There were no I/I genotypes among the five fastest marathon runners. These results suggest that the D allele of the ACE gene I/D polymorphism is associated with a high level of human endurance.

INTRODUCTION. This study investigated whether the amplitude of the first heart sound (AHS-1) and the diastolic time (DT) recorded immediately after exercising could be related to those values during exercise.METHODS. Nine male volunteers (24.6±2.9 years old) participated in this study. A discontinuous graded exercise test was performed on an electrically braked cycle ergometer. The external phonocardiograms were recorded during the test. The 10 highest AHS-1 during the last 30 sec at each stages and 10 consecutive AHS-1 immediately after each stage of exertion were measured. The DT was calculated as the systolic time subtracted from the cardiac cycle time interval assessed by the waveform of the heart sounds in the same time range as the above analysis.RESULTS. The change of AHS-1 during exercise and immediately after exercise at each stage demonstrated a significant correlation (r=0.979, p

Background Obtaining an accurate measure of physical activity energy expenditure (PAEE) can be difficult, so the simple measurement of steps per day has become widely promoted and accepted in the general population. However, the relationship between PAEE and steps per day has not been evaluated in patients with cardiovascular disease. Methods and Results A total of 77 (53 men, 24 women) cardiac rehabilitation program participants aged between 46 and 88 years were enrolled. By means of an accelerometer the step count per day, amount of PAEE, as well as time per day spent in physical activity at light ( 6 METs) intensity were evaluated for each subject. The number of daily step counts strongly correlated with total PAEE (r=0.92, p

‹Objective› To examine the effects of a twelve-week home-based bench step exercise program on aerobic capacity, lower extremity power and static balance in elderly subjects. ‹Methods› Thirty-eight elderly men and women participated in this study (age: 75±4 years, mean±SD). The subjects were randomly assigned, according to the area in which they resided, into either the exercise group (EG: 11 men, 8 women) or the control group (CG: 14 men, 5 women). The EG performed a 12-week home-based bench step exercise program (7 sessions/week, 20-30 minutes/session, bench height 15.0-20cm). They recorded the length of exercise and their physical condition. Before and after the intervention a sub-maximum bench step test, a leg extension power test and a one-leg balance test with eyes open (balance test) were performed to assess the subjects' aerobic capacity, as determined by the lactate threshold (LT), as well as lower extremity power and static balance ability. ‹Results› The LT (3.9 (3.2, 4.9) vs. 5.4 (4.8, 5.6) METs; p

The purpose of this investigation was to examine the relationship between physical activity patterns, age and Body Mass Index (BMI) in physically active elderly women. In ninety-four elderly Korean women, the number of steps taken per day and the time spent engaged in physical activity of light-, moderate- and vigorous-intensity were determined. The number of steps did not significantly differ according to age or BMI. However, time spent in moderate-intensity physical activity significantly decreased as BMI increased (P=0.049 F=3.120) and age increased (P=0.002, F=5.035). Thus, active elderly individuals should be encouraged to spend time doing moderate-intensity physical activity rather than worry about the number of steps taken each day in order to prevent obesity and an age-related decline in regular physical activity.

We investigated the association between Angiotensin I converting enzyme (ACE) gene insertion (I)/deletion (D) polymorphism and responses of hormonal factors related to vasoconstriction and volume loading of heart, enzyme activities of Renin-Angiotensin system, blood pressure and heart rate during a single bout of exercise. Six insertion homozygous (I/I) and 6 deletion homozygous (D/D) young men participated in this study. Subjects performed a multi-load exercise test at 1/2 lactate threshold (LT), LT, onset blood lactate accumulation (OBLA), and middle point of OBLA to maximum exercise load (OBLA-Peak) intensities. The duration of intensities was 10 minutes. Blood samples, blood pressure and heart rate were obtained at rest, in the last 2 minutes of every intensity, and 3 minutes after finishing exercise (recovery). However the plasma ACE activity in I/I was lower than that in D/D at rest, during exercise and recovery, and Angiotensin II was no different in I/I and D/D. Furthermore, there were no differences in plasma Renin activity, Angiotensin I, plasma aldosterone concentration, atrial natriuretic peptide, brain natriuretic peptide, adrenaline, noradrenalin, dopamine, systolic blood pressure, diastolic blood pressure, mean blood pressure, heart rate and double product at rest, during exercise and recovery. No relationship between plasma ACE activity and Angiotensin II existed, but plasma Angiotensin I and Angiotensin II had a positive correlation in I/I and D/D. This data suggests that the ACE gene I/D polymorphism is not associated with plasma Angiotensin II concentration during a single session of exercise.

Previous studies have indicated that the Angiotensin I converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism could influence human physical performance. Furthermore, a study has suggested that ACE inhibitor treatment might decrease long-term decline in muscle strength in elderly women. Thus we hypothesized that the I allele of ACE gene I/D polymorphism, which relates to lower ACE activity, might be associated with slow-decline of muscle strength in the elderly. One hundred ninety elderly people aged 72 were recruited for this study. We assessed isometric knee extension strength, leg extension power and grip strength every year for 4 years. In the preliminary measurements, physical characteristics and muscle strength were not significantly different among three genotypes. Age-related changes of the isometric knee extension, leg extension power, grip strength were similar among three genotypes. The results of this investigation suggest that ACE gene I/D polymorphism does not affect age-related change of muscle strength in the elderly.

Background Heat stress potentially has detrimental effects on brain function. Hence, cognitive function may be impaired during physical activity in a hot environment. Skin cooling is often applied in a hot environment to counteract heat stress. However, it is unclear to what extent neck cooling is effective for cognitive impairment during exercise in a hot environment. The purpose of this study was to examine the effects of temporal neck cooling on cognitive function during strenuous exercise in a hot environment. Methods Eight male young participants (mean ± SD, age = 26.1 ± 3.2 years; peak oxygen uptake = 45.6 ± 5.2 ml/kg/min) performed Spatial delayed response (DR) task (working memory) and Go/No-Go task (executive function) at rest and during exercise in the Hot and Hot + Cooling conditions. After the participants completed the cognitive tasks at rest, they cycled the ergometer until their heart rate (HR) reached 160 beats/min. Then, they cycled for 10 min while keeping their HR at 160 beats/min. The cognitive tasks were performed 3 min after their HR reached 160 beats/min. The air temperature was maintained at 35°C and the relative humidity was controlled at 70%. Neck cooling was applied to the backside of the neck by a wet towel and fanning. We used accuracy of the Spatial DR and Go/No-Go tasks and reaction time in the Go/No-Go task to assess cognitive function. Results Neck cooling temporarily decreased the skin temperature during exercise. The accuracy of the cognitive tasks was lower during exercise than that at rest in the Hot and Hot + Cooling condition (p