Resting O₂ consumption following exercise at ventilatory threshold (VT) intensity was measured in order to investigate the magnitude and duration of excess post-exercise O₂ consumption in untrained men. Nine untrained males (mean age 24.8±1.5 years) exercised for one hour at VT intensity (58.2±1.7% of VO₂max) on a cycle ergometer, and then rested for 12 h sitting in a comfortable armchair (post-exercise) . On a separate day the subjects rested for 12 h but without preceding exercise (non-exercise) . O₂ uptake (VO₂) and heart rate (HR) were measured for 5 min every 30 min throughout the 12 h rest period and again at 24 h following the exercise. High-carbohydrate meals (carbohydrate 112.8±5.1 g, protein 9.7±0.4 g, fat 1.8±0.1 g) were given to the subjects at 2, 7 and 12 h following the exercise. The total energy intake per day was 1591.7±71.8 kcal. V0₂ and HR were significantly higher, and respiratory quotient (RQ) was significantly lower at most of the measured time-points for post-exercise than for non-exercise. Total energy consumption for the 12 h rest period was 957.3±25.5 kcal for post-exercise and 840.3±15.8 kcal for non-exercise, respectively. After 24 h no difference was observed in VO₂ and HR between post-exercise and non-exercise, but RQ was significantly lower in the former than in the latter (0.86±0.05 vs. 0.90±0.04, p<0.05) . These results suggest that exercise for one hour at VT intensity enhances resting VO₂ for at least 12 h, and elevates the rate of fat utilization for at least 24 h.

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The purpose of this study was to evaluate the relationship between the position of the center of foot pressure (CFP) and control of standing posture in ten healthy men by tracking the CFP to the moving target.
Subjects were required to track a continuously moving target displayed on a screen while standing on a force plate. The velocity of the target movement was 0.05, 0.10, and 0.15 hertz (Hz) with a triangular waveform. The target was moved 30-70% within the range of the heel regarding the foot length as 100%, and the range was divided by 10%. Each subrange was named (A), (B), (C), (D) for backward movement from 70% to 30%, and (E), (F), (G), (H) for forward movement from 30% to 70%.
The standing posture control was analyzed by mean error and absolute error at turning point between target- and CFP-movement.
The mean error of backward movement was significantly greater than that of forward movement in the two forward subranges at 0.15 Hz. As for the other frequencies, there was no significant difference between directions of CFP movement. Mean error of A was significantly greater than that of B and C in higher frequencies, but there was no significant difference at 0.05 Hz. Regarding absolute error, there was no significant difference between the forward and backward turning point with a decrease in frequency. Mean error of D or E was greatest among the section in all frequencies. The ratio of the greater D or E and A or H was greatest at 0.05 Hz.
These results suggested that CFP tracking at 0.05 Hz is hardly influenced by direction and velocity of the target movement. Terefore, we conclude that controllability of the stand-ing posture differs markedly in various CFP positions. In addition, control of the standing posture in a backward direction is inferior to that in a forward one.

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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:
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.
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.
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.
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.
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.

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Several prediction equations for estimating body composition of Japanese men and women have recently been developed using a linear regression model with a combination of impedance and anthropometric measurements as independent variables. The purpose of this study was to determine the cross-validity of body density (Db) estimated from bioelectrical impedance (BI) and skinfold thickness (ST) methods in comparison with underwater weighing (UW) as a criterion reference method. Percentage body fat (%BF) was derived from Db according to the equation Brozek et al. Fifty-seven healthy Japanese women, aged 19 to 57 years, volunteered to participate in the study. Impedance was measured by use of a portable four-terminal impedance plethysmograph (Selco, SIF-891) . %BF derived from the BI method (r=0.860-0.875) was correlated with hydrodensitometrically determined %BF to a greater extent than %BF obtained using the ST method (r=0.7330.758) or ultrasound method (r=0.536-0.721) . Correlations of various anthropometric indices (r=0.655-0.691) with hydrodensitometrically determined %BF were even lower. It was noteworthy, however, that mean %BF derived from existing BI equations differed significantly from hydrodensitometrically determined mean %BF. Therefore, we attempted to develop a new equation that was applicable to Japanese adult women as follows: Db=1.1613-0.1038 (Wt⋅Z ) /Ht², where Wt=weight in kg, Z=impedance in ohms, and Ht=height in cm. The prediction accuracy of this equation was r=0.866 or SEE=0.0077 g/ml. Cross-validation of this equation on a different sample (122 Japanese women, aged 18 to 59 years) revealed a correlation of r=0.869 in terms of %BF, SEE=3.2%, and no significant difference between estimated %BF and the criterion. We suggest that the BI method is one of the most convenient, valid means of assessing human body composition, and that the newly developed BI equation could be useful particularly when the subjects are Japanese adult women in their late teens to fifties.

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Six male subjects were exposed to combined stress of heat and exercise, and their heart rate, blood pressure, oxygen uptake, skin temperature, esophageal temperature and body weight were measured. These observations were repeated 12 times for each subject under 4 levels of WBGT (Wet Bulb Globe Temperature) : 22, 26, 30, 32.5°C at rest and at 2 levels of exercise intensity : 150 W/m² (Ex. 150W) and 250 W/m² (Ex. 250 W) . The results obtained were as follows:
1. Significant differences were found in heart rate, oxygen pulse and rate pressure product at 32.5t WBGT and Ex. 150 W and at 30 and 32.5t WBGT and Ex. 250W compared with those at 22t WBGT.
2. Significant increases in esophageal temperature were observed at 32.5°C WBGT and Ex. 150 W and at 30 and 32.5t WBGT and Ex. 250 W.
3. The body weight loss at 26, 30 and 32.5 C WBGT was significantly higher than that at 22°C WBGT for both Ex. 150 W and 250 W.
4. These results suggest that there is a risk of heat exhaustion at WBGT higher than 30-32.5°C under mild exercise and above 26-30°C WBGT at a moderate exercise level. The upper limit for moderate exercise (Ex. 250W) is suggested to be 30°C WBGT.

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The purpose of the present study was to investigate the relationships of physical fitness, body mass index (BMI), waist-hip ratio (WHR) and sex hormone binding globulin (SHBG) with lipid and glucose metabolism in premenopausal obese women aged 32 to 49 yrs (n=24) . WHR was significantly correlated with HDL-C, HDL₂-C and Apo B, but not correlated with BMI %fat, maximal oxygen uptake (VO₂max), triglyceride (TG), very low density lipoprotein % fat, and Apo A 1. VO₂max/kg was significantly associated with BMI, TG, HDL-C, HDL₂-C, Apo Al, low density lipoprotein (LDL), SHBG, glucose metabolism at rest and during oral glucose tolerance test (OGTT) . The SHBG was strongly correlated with HDL-C, HDL₂-C and Apo A 1. In multiple regression analysis, it was observed that SHBG was one of the independ-ent predictor of HDL-C, HDL₂-C and Apo Al, that VO₂max was good predictor of LDL, Apo B and glucose metabolism at rest and during OGTT, and that BMI was one of the determinat of TG and VLDL. From these results, we concluded that lipid metabolism was independently associated with aerobic work capacity, SHBG, BMI as well as WHR, and that glucose metabolism was independently associated with aerobic work capacity.

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