RESUMEN
This prospective study was designed to clarify the association between the incidence of falls and physical fitness in healthy community-dwelling elderly people without history of fall-related injuries within 1-5 years before the baseline assessment. Six hundred and one elderly subjects aged 60-79 years who lived independently participated in baseline assessments from March 2002 to March 2004, and were followed up for one year to detect falling. Demographic items (age and sex), chronic disease, self-rated health, difficulty in performing any activity, tendency to stay at home, body mass index (BMI), %vital capacity, handgrip and knee extension strength, stepping rate, one-leg standing with eyes opened, trunk flexion at sitting position, maximum walking speed, instrumental activity of daily living (IADL), and General Health Questionnaire (GHQ30) were assessed at baseline. Four hundred and eighty-one participants (80.0%) completed the 1-year follow-up.The fall incidence was 13.1%. In men, fallers had lower BMI and decreased maximum walking speed, however, neither showed significant odds ratio (OR) for fall. In women, fallers had lower knee extension strength and the ratio of weak side to strong side (WS/SS ratio) in knee extension strength compared to non-fallers. The age-adjusted OR for fallers in the lowest quartile (knee extension strength＜0.681kg/BW) was 3.07 (95%CI : 1.02-9.22) compared to highest quartile (＞0.980 kg/BW), while the multiple-adjusted OR was not significant (OR＝2.88, 95%CI : 0.94-8.79). However, the multiple-adjusted OR for fallers in the lowest quartile of the WS/SS ratio in knee extension strength (＜0.771) was 4.49 (95%CI : 1.40-14.37) compared to highest quartile (＞0.947).As for conclusion, without history of fall-related injuries, only a weak association between falls and physical fitness was observed in men. In women, the unbalanced knee extension strength was associated with falls. The WS/SS ratio in knee extension strength might be a key factor in predicting falls in women.
RESUMEN
The purpose of this study was to examine the association between the pedometer-determined steps per day and physical fitness in order to evaluate the usefulness of the pedometer-determined physical activity to help individuals meet the recommended exercise target level of the Ministry of Health, Labour and Welfare (MHLW). The subjects consisted of 222 men and 172 women aged 71 years in community-dwelling elderly. The subjects wore a pedometer for 7 consecutive days to measure daily steps. The functional capacity was assessed based on the Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG-IC) and self-reported performance of tasks (stair-climbing and chair-rising). Physical fitness tests included handgrip strength, knee extensor strength, leg extensor power, stepping, one-leg standing time with eyes open and maximal walking speed at 10 m. The men and women took on average 6,561±2,907 and 6,329±2,451 steps/day, respectively. Our subjects seemed to be highly functioning elderly, because the total scores of TMIG-IC (maximum : 13 scores) were on average 12 for men and women. The average of steps/day was significantly correlated with stair-climbing, chair-rising and knee extensor strength in men and women, and with body weight, body mass index (BMI), percent body fat (%Fat) and leg extensor power in women. The BMI and %Fat levels were significantly lower while the handgrip strength and knee extensor strength were significantly higher in women who attained to the level of the pedometer-determined physical activity as recommended by the MHLW.The present study suggests that both men and women who take a lot of steps on a daily basis tend to demonstrate excellent leg strength and thus have a good ability to perform the tasks of daily living. In addition, the degree of obesity tends to be lower in women who regularly take a lot of steps. In addition, the number of daily steps taken has been recognized to be linked to gender, and such a link has also been suggested to be stronger in women than in men.
RESUMEN
This study was conducted to clarify the validity and availability of inclination of exponential curve-fitting model for oxygen uptake (VO<sub>2</sub>) and heart rate (HR) during incremental exercise (I-ECOH) as an index of cardio-pulmonary functional reserve in patients with ischemic heart disease (IHD). A treadmill exercise test was used to measure the VO<sub>2</sub>(L/kg/min) and HR (beat/min) during incremental exercise of all subjects. I-ECOH was derived from the following equation : HR=A·exp<sup>B·VO2</sup>. The constant "B" represents I-ECOH. The following two identifications were made : 1) the relation between peak oxygen uptake (VO<sub>2</sub>peak) and I-ECOH in IHD patients with normal left ventricular function and with chronic heart failure (CHF); 2) the relation between I-ECOH and the New York Heart Association (NYHA) functional classification of IHD patients with CHF.There were significant differences among IHD patients with normal left ventricular function, CHF patients, normal controls and long distance runners in I-ECOH and VO2peak, respectively (p<0.001). There were inverse correlations between I-ECOH and VO2peak in IHD patients with normal left ventricular function (r=-0.64, p<0.001) and CHF (r=-0.63, p<0.001). I-ECOH could be used to discriminate effectively between NYHA functional classes (p<0.001).In conclusion, these results suggest that I-ECOH is adequate and useful as an index of cardio-pulmonary functional reserve in patients with ischemic heart disease.
RESUMEN
A study was conducted to clarify the validity and availability of inclination of exponential curve-fitting model for oxygen uptake (VO<SUB>2</SUB>) and heart rate (HR) during incremental exercise (IECOH) as an index of cardio-pulmonary functional reserve in healthy subjects. A treadmill exercise test was used to measure the VO<SUB>2</SUB> (L/kg/min) and HR (beat /min) during incremental exercise of all subjects. The IECOH was derived from the following equation : HR=A⋅exp<SUP>B·VO<SUB>2</SUB></SUP>. The constant “B” represents the IECOH. The following three identifications were made : 1) the relationship between maximal oxygen uptake (VO<SUB>2</SUB>max) and IECOH in 82 healthy males ; 2) the relationship between IECOH and age in 428 healthy males and females ; 3) the effect of physical training in 8 healthy males.<BR>There was inverse correlation between IECOH and VO<SUB>2</SUB>max (r= -0.824) . And also, there were inverse correlations between IECOH detected from submaximal tests and VO<SUB>2</SUB>max (above r=-0.6) . There were no differences in the IECOH detected from maximal and submaximal tests. In Bland-Altman plot method, accuracy of measurment in the IECOH detected from submaximal exercise test was precise. There was a significant relationship between IECOH and age in male and female subjects (r=0.499 and r=0.310, respectively) . Physical training increased VO<SUB>2</SUB>max and decreased IECOH significantly. The VO<SUB>2</SUB>max before and after physical training correlated inversely with the IECOH before and after physical training (r=-0.514) .<BR>In conclusion, these results suggest that IECOH is adequate and useful as an index of cardio-pulmonary functional reserve which can be measured by the submaximal exercise test in healthy subjects.
RESUMEN
This study examined the effects of physical training on exercise hyperpnea (EH) in patients on hemodialysis (HD) . In baseline, 17 (trained group) and 12 (control group) patients on HD performed symptom limited exercise test using a treadmill. Trained group, but not control group, exercised 2 to 3 times weekly on non-dialysis days under medical supervision. Exercise testing was repeated 20 weeks after the baseline. Ventilatory response to exercise was evaluated using the regression slope relating minute ventilation (VE) to carbon dioxide output (VCO<SUB>2</SUB> ) during incremental exercise (VE/VCO<SUB>2</SUB> slope) below the point of respiratory compensation. In trained group, VE, oxygen uptake ( VO<SUB>2</SUB>) and VCO<SUB>2</SUB> at peak exercise increased and VE/VO<SUB>2</SUB> and VE/VCO<SUB>2</SUB> decreased after physical training, respectively. No change was observed in control group. VO<SUB>2</SUB> at the anaerobic threshold increased in trained group, but not in control group. The post training VE/VCO<SUB>2</SUB> slope (33.9±5.0) was significantly (p<0.05) lower than the pre-training slope (38.0± 4.8) and remained constant in control group. In trained group, changes in the VE/VCO<SUB>2</SUB> slope correlated with those in peak VO<SUB>2</SUB> (p<0.05) . These results suggest that physical training decreases EH in patients on HD and that it correlates with changes in exercise tolerance.
RESUMEN
A study was conducted to clarify the effect of hyperoxia (HO) on exercise tolerance andhemodynamics in patients with ischemic heart disease (IHD) . The subjects were 10 patients with serious IHD who showed ischemic ST depression during low-intensity exercise testing. In all subjects, cardiopulmonary exercise testing (CPX) was performed using two types of inhalation : normoxia (NO) and HO (O<SUB>2</SUB>: 60%, N<SUB>2</SUB>: 40%) . Heart rate (HR), blood pressure (BP), rating of perceived exertion (RPE), elapsed exercise duration and pressure rate product (PRP) were measured, and ECG was recorded during CPX according to the Bruce protocol. The peak oxygen uptake (VO<SUB>2</SUB>peak) was calculated using the appropriate formula. These data were compared between the NO and HO groups, and the following results were obtained.<BR>ST depressions on ECG, BP, HR and PRP after 20 min of rest showed no changes under NO. The other hand, only ST depression was improved after 20 min of rest under HO. The exercise duration in HO group was longer than in the NO group, and the VO<SUB>2</SUB>peak in the HO group was higher than in the NO group. However, peak RPE showed no significant difference between the HO and NO groups. The incidence of ST depression as an endpoint of CPX showed no significant difference between the two groups. BP, HR and PRP at the CPX endpoint showed no significant differences between the HO and NO groups. In patients whose exercise duration was prolonged beyond the mean value by HO, peak HR and PRP were increased significantly. However, this tendency was not seen in patients whose exercise was prolonged for less than the mean value.<BR>In conclusion, these results suggest that an increase in the oxygen supply to peripheral working muscles may play an important role in increasing exercise tolerance under HO in IHD patients.
RESUMEN
A study was conducted to clarify training ability in the recovery phase after coronary artery bypass graft surgery (CABG) . Thirty-one patients who underwent CABG were divided into four groups according to the degree of revascularization and graft patency: complete revascularization with graft patency (group A), complete revascularization without graft patency (group B), incomplete revascularization with graft patency (group C) and incomplete revascularization without graft patency (group D) . In all patients, exercise training was started one month after CABG and continued for one month. Treadmill exercise testing was performed at three points during the clinical course (one month before CABG, one month after CABG and at the end of exercise training) . Functional aerobic impairment (FAT), myocardial aerobic impairment (MAT), peripheral circulatory impairment (PCI) and electrocardiogram were measured at these points. The results obtained were as follows:<BR>1) FAI was improved significantly after CABG as compared with before CABG in groups A and C, and was also improved significantly after exercise training as compared with before training in groups A and C. The degree of improvement in FAI in group A was larger than in group C.<BR>2) Althought MAT was improved significantly after CABG as compared with before CABG in groups A and C, it was improved significantly after exercise training as compared with before training only in group A.<BR>3) PCI remained unchanged before and after CABG in all groups. However, it was improved significantly after training as compared with before training in groups A and C.<BR>4) The number of patients with a positive finding in the exercise test was reduced by CABG in all groups, and was decreased by training only in group A. However, CABG produced a significant decrease in groups A, B and C.<BR>In conclusion, the present findings suggest that while graft patency is probably a major factor, the degree of revascularization may play only a subsidiary role in determining trainability soon after CABG.
RESUMEN
Physical training has been shown to improve glucose tolerance and insulin action in peripheral tissues. In the present study, regular (R) and high (H) -dose euglycemic clamp procedures were performed to determine the effects of different types of physical training on insulin action (sensitivity/responsiveness) in 10 long-distance runners (LR), 10 weight-lifters (WL) and 12 healthy controls (HC), The amount of infused glucose (glucose metabolism, GM) during euglycemic clamping is a measure of the peripheral tissue sensitivity and/or responsiveness to insulin. For R clamping, when GM was calculated per unit body weight (BW), GM in LR (11.92±1.22 mg/kg BW·min) and WL (9.28±0.63 mg/kg BW·min) was significantly (P<0.05) higher than that in HC (7.44±0.39 mg/kg BW·min) . When calculated per unit lean body mass (LBM), LR (15.07±1.56 mg/kg LBM·min) differed from HC (9, 15±0.59 mg/kg LBM·min, P<0.05), whereas the value in WL (11.50±0.93mg/kg LBM·min) was identical to that in HC. For H clamping, there was no significant change in these three groups when GM was calculated per unit BW or LBM. These results suggest that enhancement of insulin action by physical training is due to an increase in insulin sensitivity, rather than to an increase in insulin responsiveness, and that aerobic exercise, for example long-distance running, is more effective for the improvement of decreased sensitivity to insulin, which is observed in patients with simple obesity and diabetes, than anaerobic exercise such as weight-lifting.