Phagocytic cells, polymorphonuclear leucocytes and macrophage, play an important role in a non-specific cellular immunity which is first defense line for infectious disease. The purpose of this paper is to clarify combined effects of stressful exercise and sleep disturbance on rat non-specific cellular immunity represented by yields of cells from bronchoalveolar lavage and superoxide generating capacity of alveolar macrophage.
Male Wistar rats ( 5 weeks old) were divided into following 4 groups. 1) Training group; exercised on a treadmill at a belt speed of 35 m/min for 45 min/day, 2) Jet Lag group; noninvasive sleep disturbance by the shifted day/night time every 2 week interval, 3) Training + Jet Lag (T+ J) group ; exercised on a treadmill with sleep disturbance, that we assumed one of chronic fatigue model in this paper, and 4) Control group ; set sedentary condition.
After 6 weeks of the experiment, 2 groups were newly selected from T + J group for the examination of rest effects on the chronic fatigue model rats. And to examine the combined effects of stressful exercise and sleep disturbance on matured rats (11 weeks old), Acute Training + Jet Lag (AT+J) group was selected from the Control group.
Rats were sacrificed at 11 and 17 weeks old. T + J group seemed to be able to adapt first 6 weeks but negative effects were found out at 17 weeks old. Same phenomena were also recognized in AT + J group. These results suggest that the chronic fatigue model rats may easily catch the infectious disease and there are possibility that both stress, stressful exercise and sleep disturbance, negatively affects the non-specific cellular immunity, especially after maturation.

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Structural and mechanical adaptations of the femur and tibia to jump and run training were investigated in female Fischer 344 rats. Rats aged 4 weeks were trained for 8 weeks after 1 week of stabilization. In experiment A, the forced run-trained (speed : 30 m/min, duration: 1 h/day) group was compared with the control group. In experiment B, voluntary run and jump-trained (height : 40 cm, 100 times/day) groups were compared with the control group. The limb bones of the jump-trained group had greater cross-sectional areas and greater maximum load in a fracture test than the limb bones of the control group, but there was no significant difference in bone length between the jump-trained group and the controls. The bone adaptations to forced running and voluntary running were similar. The limb bones of both run groups were longer than those of each control group. The cross-sectional areas and the maximum load in the run-trained groups were greater than those in each control group but less than those in the jump-trained group. The present results indicate that bone adaptations to jump training and run training differ and that jump training is more effective for building stronger bones.

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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 (O₂: 60%, N₂: 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 (VO₂peak) was calculated using the appropriate formula. These data were compared between the NO and HO groups, and the following results were obtained.
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 VO₂peak 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.
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.

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A cross-sectional study was carried out to investigate the effect of physical exercise in daily lives of healthy women on the aging process in terms of maximal aerobic capacity (VO₂max), body fat tissue mass (FTM), lean tissue mass (LTM), bone mineral density (BMD), serum triglyceride (TG), total cholesterol (TC), HDL-C and LDL-C concentrations, and systolic (SBP) and diastolic blood pressure (DBP) . These parameters are considered as risk factors of cerebrovascular disease and/or osteoporosis, which are the main causes of becoming bedridden and demented in middle-aged and older women. One hundred sixty-five healthy female volunteers aged 20 to 76 years participated in the study, 82 of whom were postmenopausal with a mean age at menopause of 49.7±3.1 years. Eighty-two of the subjects had been exercising regularly by jogging, swimming, aerobic dancing, or playing tennis more than twice a week for 2 years (Ex group), whereas 83 individuals had not been engaging in regular exercise (Cont group) . Serum lipid concentrations, SBP and DBP measurements at rest and treadmill VO₂max and HRmax measurements were determined in the morning after an overnight fast. Whole-body BMD (TBMD), head, lumbar, arm and leg BMD, FTM and LTM were measured by dual-energy X-ray absorptiometry one to two hours after a light lunch. The mean and SD of each measurement were calculated for five-year age groups between 40 and 60 years and one group each under 40 and over 60 years.
The results were as follows:
1, VO₂max (r=-0.590) and HRmax (r=-0.632) decreased significantly with age. The VO₂max of the Ex group was significantly higher than that of the Cont group in all each age groups. However, no differences in the aging process in terms of HRmax were found between the two groups.
2, Resting SBP (r=-0.391) and DBP (r=0.315) increased significantly with age. However, no hypertensive individuals (160/95 mmHg-) were found among the 165 subjects.
3. Only serum TC (r=0.346) and LDL-C (r=0.339) among the blood constituents measured changed with age. No changes in serum HDL-C were detected with age. Lower TC (189.2±23.3 mg/dl) and higher HDL-C (72.2±10.9 mg/dl) were observed in eleven runners (49.7±7.7 years) among the subjects who participated frequently in official races than in subjects of the same ages in the Cont group. The highest serum HDL-C (75.8±15.8 mg/dl) and HDLC/TC ratios (0.362) were noticed among the subjects (n=26) who both regularly exercised and consumed alcoholic beverages.
4. A tendency for FTM to increase and LTM to decrease with age were observed in both groups, and a lower %FTM (percentage of FTM to body weight) and higher %LTM were evident in the Ex group. Differences in %FTM and %LTM between the Ex and Cont groups at 40-45 years were significant.
5. Partial and whole BMDs decreased significantly with age (TBMD-Age ; r=- 0.527) . Significantly higher leg BMDs in both the 20-39-year and 40-45-year groups, and spine and TBMD in the 20-39 years in the Ex group, who were premenopausal women, were shown. No significant differences in BMDs between the two groups were observed in postmenopausal women, but the Ex group tended to have higher partial and whole BMDs. The postmenopausal official race runners (n=5.52.6-1.5years) also had higher TBMD and leg BMD values than subjects of the same ages in the Cont group.
6. Investigation of correlations between VO₂max, LTM, FTM, BMDs and serum lipid concentrations, yielded a significantly higher correlation (r=0.669) between LTM (kg) and absolute VO₂max (1/mm) . Although VO₂max per LTM (VO₂max/LTM) decreased with age (r=-0.595), VO₂max/LTM in the Ex group was significantly higher than in the Cont group in each age group. The VO₂max per body weight (ml/kg/min) was negatively correlated with %FTM (r=-0.442) and positively correlated with

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A conducted to determine 1) the effect of high-velocity movement in resistance training with a constant load on the velocity of movement after training and 2) the differences in the effect on muscle hypertrophy according to training velocity. Fourteen of the total subjects (male; n=10, female ; n=7) were placed in the experimental group and agreed to participate in 8 weeks of training sessions (4 times a week) . Five of the 17 subjects were in control a group before the training session. Subjects performed elbow extension and flexion exercise using 50% of one repetition maximum (% 1 RM) load. The exercise session consisted of 6 sets of 10 repetitions and 30s of rest was taken between the sets. The subjects in the experimental group trained their arms using two different protocols ; one was high-velocity movement performed as rapidly as possible (Type R), the other was low-velocity movement performed at a constant and slow velocity (Type S) . Isokinetic torque in elbow flexion was measured at angular velocities of 60, 180, 300 deg/s, respectively, during elbow flexion performed under different constant loads of 0, 30, 50% 1 RM, and the muscle cross-sectional area (CSA) of the elbow flexor was determined before and after training. It was found that Type R did not increased isokinetic torque at 300 deg/s significantly after training. However, the increase in angular velocity of elbow flexion in Type R exercise tended to be higher than in Type S exercise. The increase in CSA [Type S; 11.2%, Type R ; 14.2%] was significantly higher in Type R exercise (p<0.05) . These results suggest that high-velocity movement with a constant load in resistance training might increase the angular velocity of movement in the same mode, but might not produce a change in isokinetic strength, which involves a different mode of muscle contraction. Muscle hypertrophy would be induced to a greater extent by high-velocity movement than by low-velocity movement in resistance training with a constant load.

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This study was carried out to determine the relationship between health status and physical fitness, and the contribution of each element of physical fitness to the health status of middle-aged and elderly men and women. The subjects were 889 males and females aged 30 to 69 years. Physical fitness tests and medical check ups were performed. According to health status, the subjects were divided into two groups ; the healthy group (HG, n=348) and the unhealthy group (UG, n=207) . Multiple discriminant analysis was applied to the multivariate data. Correct discriminant probabilities of multiple discriminant functions to discriminate the HG and UG were 70.2% and 68.2% for men and women, respectively. These results suggested that there was a relatively strong relationship between health status and the level of physical fitness in both men and women. The contribution of each element of physical fitness to health status was evaluated by correlation coefficients between the discriminant score representing health status, and performance on each element of the physical fitness test and age. Age and muscle endurance contributed significantly to health status in both men and women. In addition, close relationship was seen between health status and elements of cardiorespiratory endurance, balance, and muscle strength in men, while change in physique correlated with health status in women. From these findings, it was concluded that exercise programs for health promotion in middle-aged and elderly people should be provided separately with consideration of the degree to which these specific elements contribute to health status.

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