The cardiovascular adaptation at the onset of voluntary static exercise is controlled by the autonomic nervous system. Two neural mechanisms are responsible for the cardiovascular adaptation: one is central command descending from higher brain centers, and the other is a muscle mechanosensitive reflex from activation of mechanoreceptors in the contracting muscles. To examine which mechanism played a major role in producing the initial cardiovascular adaptation during static exercise, we studied the effect of intravenous administration of gadolinium (55 mol/kg), a blocker of stretch-activated ion channels, on the increases in heart rate (HR) and mean arterial blood pressure (MAP) at the onset of voluntary static exercise (pressing a bar with a forelimb) in conscious cats. HR increased by 31 Ϯ 5 beats/min and MAP increased by 15 Ϯ 1 mmHg at the onset of voluntary static exercise. Gadolinium affected neither the baseline values nor the initial increases of HR and MAP at the onset of exercise, although the peak force applied to the bar tended to decrease to 65% of the control value before gadolinium. Furthermore, we examined the effect of gadolinium on the reflex responses in HR and MAP (18 Ϯ 7 beats/min and 30 Ϯ 6 mmHg, respectively) during passive mechanical stretch of a forelimb or hindlimb in anesthetized cats. Gadolinium significantly blunted the passive stretch-induced increases in HR and MAP, suggesting that gadolinium blocks the stretch-activated ion channels and thereby attenuates the reflex cardiovascular responses to passive mechanical stretch of a limb. We conclude that the initial cardiovascular adaptation at the onset of voluntary static exercise is predominantly induced by feedforward control of central command descending from higher brain centers but not by a muscle mechanoreflex. muscle mechanosensitive receptors; stretch-activated ion channels; mechanical stretch of skeletal muscle; exercise pressor reflex; conscious cats

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[Purpose] The purpose of this study was to identify factors related to physical characteristics and lifestyle that affect pulmonary function. [Subjects and Methods] Ninety seven healthy male workers were recruited for this study, and basic information and details about lifestyle were collected. Body composition analyzer and visceral fat measuring device were conducted as measurements. Pulmonary function was measured using spirometer. A multiple stepwise linear regression analysis was performed with pulmonary function as the dependent variable. Variables with a significant association with pulmonary function on univariate analysis were imputed as independent variables. [Results] Height, fat free mass, upper extremity muscle mass, lower extremity muscle mass, and trunk muscle mass had significant positive correlations with FEV1 and FVC. Age, percentage of body fat, and visceral fat area were negatively correlated with FEV1 and FVC. Regarding the association between pulmonary function and lifestyle, a significant difference was found between the smoking index and the presence or absence of metabolic syndrome risk factors and both FEV1 and FVC. The multiple stepwise linear regression analysis with FEV1 as the dependent variable, adjusted for age and height, revealed that visceral fat area and fat free mass were significantly associated with FEV1. A similar analysis, FVC as the dependent variable identified visceral fat area. [Conclusion] FEV1 was independently associated with visceral fat area and fat free mass. FVC was independently associated with visceral fat area. These results may be valuable in preventing the decrease in respiratory function and, hence, in further preventing the onset of COPD.

[Purpose] Current studies report that patients with chronic obstructive pulmonary disease (COPD) may also have arteriosclerosis. This study aimed to investigate the relationship between respiratory function and arterial stiffness in healthy workers using the brachial-ankle pulse wave velocity (baPWV). [Subjects and Methods] This study included 104 male Japanese workers without COPD. We collected participant information and measured hemodynamics, body composition, and respiratory function. [Results] In the correlation analysis, baPWV showed a significant positive correlation with age, smoking index, systolic blood pressure, diastolic blood pressure, and heart rate, and a significant negative correlation with height, fat free mass, lower limb muscle mass, forced vital capacity (FVC), and forced expiratory volume in one second (FEV1). In multiple regression analysis using factors other than baPWV and respiratory function as adjustment variables, both FVC and FEV1 showed a significant negative relationship with baPWV (p=0.009 and p=0.027, respectively). FEV1/FVC was not significantly related to baPWV (p=0.704). [Conclusion] The results of this study indicated that FEV1/FVC and the proportion of FEV1 predicted, which are indicators of airflow limitation, are not predictors of baPWV in workers without airflow limitation. However, since baPWV showed a significant negative relationship with FVC and FEV 1, the reduction in respiratory function that does not cause airflow limitation, such as FVC or FEV1 decline, may be related to an increase in the risk of arterial stiffness.

Decreased respiratory function associated with aging leads to the onset of chronic obstructive pulmonary disease (COPD) and increased risk of death in the elderly. Prevention of a decline in respiratory function from a young age is important. This study aimed to clarify the factors that affect decreased forced expiratory volume in one second (FEV1)/forced vital capacity (FVC), an index of obstructive respiratory disorder caused by airway obstruction, by considering the influence of body composition and lifestyle. We recruited 262 employed adult men and determined their lifestyle-related factors, including smoking status, past or current secondhand smoke (SHS) exposure, exposure to SHS outside the home, and physical activity (PA). Body composition and respiratory function were also measured. The data were then compared with those of non-smokers using logistic regression analysis, adjusting for age. We also investigated factors influencing FEV1/FVC using multiple regression analysis, adjusting for age, height, smoking status, and lifestyle. Current smokers and heavy smokers exhibited significantly lower amounts of PA and had a higher body fat%, visceral fat area, prevalence of cohabitation with smokers, and frequency of SHS exposure outside the home, and FEV1/FVC was significantly lower in heavy smokers. A multiple regression analysis revealed that FEV1/FVC was associated only with the frequency of SHS exposure outside the home. It is important for occupational health personnel of a company to advise both non-smokers and smokers to avoid SHS to prevent chronic obstructive pulmonary disease onset. This needs to be coupled with encouragement to quit smoking, especially for heavy smokers.

Patients with fibrosing interstitial lung disease (FILD) have poor health-related quality of life (HRQOL). We analyzed predictors of short-term improvement of HRQOL after starting pulmonary rehabilitation (PR) in moderate to severe FILD patients. This study involved 28 consecutive patients with FILD (20 males, median age of 77.5 years), who participated in PR program of our hospital for >6 weeks. The St. George’s Respiratory Questionnaire (SGRQ) score and the 6-min walk distance (6MWD) were evaluated before and after PR, and the predictors of efficacy of PR were analyzed. The duration from diagnosis of FILD to start of PR showed a positive correlation with the increase in the SGRQ score, and the baseline SGRQ score showed a negative correlation with increase in the 6MWD. The FILD subtype, modified Medical Research Council score, and treatment history were not associated with the endpoints. According to the receiver operating characteristic curve (ROC) analyses, starting PR within 514 days after diagnosis of FILD was a significant favorable predictor of improvement in the SGRQ total score more than a minimal clinically important difference of 4. In this study, early intervention of PR and lower SGRQ score were associated with the favorable response to PR. PR for FILD should be initiated early before the disease becomes severe.

No study has examined whether the determinants of longitudinal changes in brachial-ankle pulse wave velocity differ depending on the baseline brachial-ankle pulse wave velocity values. Therefore, this study aimed to extract these determinants in high-and low-value groups based on the FY2014 brachial-ankle pulse wave velocity values. [Participants and Methods] Participants were 97 male workers who underwent continuous health assessments from FY2014 to four years later. Their demographic, lifestyle, body-composition, and hemodynamic data were recorded. First-year data were subtracted from data obtained four years later for each continuous variable item, and the difference divided by the number of years was considered as the annual change. Based on the first-year median brachial-ankle pulse wave velocity, participants were classified into high-and low-brachialankle pulse wave velocity groups, i.e., high-and low-value groups, respectively. Multiple regression analysis was performed with the annual change in brachial-ankle pulse wave velocity serving as the dependent variable for both groups.[Results] In comparison with the values obtained in the first year, brachial-ankle pulse wave velocity obtained four years later increased significantly in the low-value group and tended to increase in the high-value group. Increased visceral fat area in the high-value group and increased diastolic blood pressure and heart rate in the lowvalue group were associated with worsening brachial-ankle pulse wave velocity. [Conclusion] The determinants of longitudinal changes in the brachial-ankle pulse wave velocity differed depending on the baseline brachial-ankle pulse wave velocity values.

[Purpose] To clarify the relationship between motor imagery ability evaluated using 3 different methods and performance changes representing the effect of mental practice (MP). [Subjects and Methods] Twenty healthy students performed a motor task before and after MP to examine changes in their performance as an outcome of such practice, using the Movement Imagery Questionnaire-Revised Japanese Version (JMIQ-R), mental chronometry, and mental rotation for the evaluation of motor imagery ability. Subsequently, the relationship between performance changes and the effect of MP was examined.[Results] The students' levels of performance markedly improved after MP, revealing a moderate correlation between mental chronometry results and the amount of change in performance.[Conclusion] Mental chronometry-based motor imagery ability may be associated with the effect of MP.