ABSTRACT
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.
ABSTRACT
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.
ABSTRACT
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.
ABSTRACT
A study was performed to evaluate the physical exercise characteristics of 29 Japanese elite judo athletes by treadmill exercise test. Functional aerobic impairment (FAI), heart rate impairment (HRI) and peripheral circulatory impairment (PCI) in the judo athletes were not significantly different from those of normal sedentary subjects. However, myocardial aerobic impairment (MAI) was lower than in normal sedentary subjects. %VO<SUB>2</SUB>max at the anaerobic threshold (AT) was 57.5±3.3% in male, and 57.0±4.3% in female judo athletes. %HRmax at AT was 72.4±3.8% in males, and 75.2±5.3% in females.<BR>These findings suggest that functional aerobic capacity and peripheral circulatory function in Japanese elite judo athletes are not significantly different from those of normal sedentary subjects, but that judo athletes have high left ventricular function.<BR>The blood biochemical profile and urinalysis date revealed that values of muscle injury enzymes, plasma uric acid and cholesterol were increased with relatively high freqency in elite judo athletes. Similar data were also obtained in individuals with suspected diabetic nephropathy and rhabdomyolysis.