The purpose of this study was to investigate the possible individual difference in temperature regulating ability during identical relative exercise load under various temperature environments.
Seven healthy males, aged 21 to 26 years, performed bicycle ergometer exercise of 60% VO₂max for 60 minutes. All exercises were carried out in a climatic chamber under the conditions of 15°C (RH=70%), 25°C (RH=55%) or 35°C (RH=45%) . Herat rate, O₂ consumption, pulmonary ventilation, rectal temperature, mean skin temperature, local sweat rate at the lower part of scapula and total sweat rate were determined intermittently through the experiments. Moreover, heat loss by evaporation, radiation, convection and effective sweat rate was calculated using the heat valance equations.
The results obtained are as follows :
1. The increase in rectal temperature at the end of exercise was almost identical in 15°C and 25°C but significantly higher in 35°C.
2. A significant positive correlation was observed between mean skin temperature (ΔTsk) at the end of exercise and effective sweat rate (r=0.468, p<0.05) during exercise.
3. Inspite of the equality of relative exercise intensity (60%VO₂max), marked individual variations were observed in rectal temperature during exercise.
4. The subjects who showed marked increase in rectal temperature during exercise showed less marked increase in mean skin temperature in 15°C and 25°C and less marked increase in local sweat rate in 35°C than other subjects.
It would be concluded that the main cause of individual variation in rectal temperature during exercise depends on difference in evaporative heat loss in hot environment and difference in skin temperature in mild or cold environment.

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The purpose of this study is to analyze the plasma proteins of physical education athletic and general students (aged 19-22) before their breakfast by two-dimensional electrophoresis.
The results of this study, a protein which has not been found in any original report yet is detcted from physical education athletic students before breakfast.
This protein was not detected from general studenets before breakfast. This protein was detected at the position of pI5.0, molecular weight of about 70, 000 on two-dimensional polyacrylamide gel electrophosis under non-denaturing codition, but it showed a molecular weight of about 30, 000 on SDS-polyacrylamide gel electrophoresis.
As far as this research is concerned, neither special physical education athletic students and nor general students were observed in changes of two-dimensional electrophoretic patterns of blood cell cytosol and blood cell membrane proteins.

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Myosin light chain patterns were examined in single fibers from the extensor digitorum longus (EDL) and soleus muscles of Wistar strain rats. The fiber type composition of both muscles was also determined to estimate the relationship between myosin light chain patterns and histochemical fiber types.
The results were summarized as follows ;
1. All of single fibers from the EDL muscle was typical fast type which contained fast light chains only (fLC 1·fLC 2·fLC 3), except that there was one mixed type fiber cotaining both fast and slow light chains (fLC 1·fLC 2·sLC 1·sLC 2) .
2. There were two myosin light chain patterns in single fibers from the soleus muscle. One was typical slow type which contained slow light chains only (sLC1·sLC 2) and the other, mixed type in which fast and slow light chains coexisted. Mixed type fibers were divided into eight groups based on the light chain composition. The percentage occurence of typical slow type and mixed type fibers was 35.4% and 64.6%, respectively.
3. The average percentage of type II fibers was 94.6% in the EDL muscle 5.4% in the soleus muscle.
4. These results suggest that both fast and slow skeletal muscles contain mixed type fibers. The results further imply that in slow skeletal muscle, myosin light chain pattern of mixed type occurs not only in type II but also in type I fibers.

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Cardiovascular responses to weight-lifting exercise were studied on eight experienced weight lifters, with an aim at examining the difference in the responses between two weight-lifting forms of “Snatch”and“Jerk”and that between the subjects. The exercise was performed successively at five exercise intensities interposing 3.5-min rest in sitting position : 10 repetitive lifts for 30 sec with 20, 40 and 60% of the maximum single lift, 3 repetitive lifts within 25 sec with 80% and finally the maximum single lift (100%·1 RM) . Each of“Snatch”and“Jerk”experiments was done on separate days. Blood pressures (BP) in sitting position were measured in sphygmomanometry at rest and 30 sec before and 12 sec after exercise. Heart rate (HR) was measured in a 30 sec pooling method throughout the experimental period. The following results and suggestions were obtained.
(1) Resting HR and BP that were measured before the exercise were not different between“Snatch”and“Jerk” experiments.
(2) At each exercise intensity, HR during exercise (exercise HR) was slightly greater in“Snatch”than in “Jerk”, the difference being not significant. Exercise HR at 100%·1 RM was 114±9 (SD) beats/min in “Snatch”and 111±7 beats/min in“Jerk”.
(3) Anticipative tachypnea occurring prior to exercise became stronger as the weight to be lifted became heavier.
(4) At each exercise intensity, the inter-subject difference in exercise HR was due to the difference in the absolute weight lifted for subjects weighing lighter, and for those weighing heavier it was due to the differences in the resting HR as well as in the absolute weight lifted.
(5) Thus, exercise HR in weight lifting that requires nearly maximal dynamic contraction for 10-30 sec seems to be determined not only by the exercise intensity but also by resting HR, anticipative tachypnea and experience.
(6) At lower exercise intensities, post-exercise BP was significantly higher in“Snatch”than in“Jerk”, while the difference between the two weight-lifting forms disappeared at higher intensities. At 100%·1 RM, post-exercise BP was around 145 mmHg for the systolic pressure and 77 mmHg for the diastolic pressure in both lift forms.
(7) At each exercise intensity, the inter-subject difference in post-exercise BP was accounted for by that in the resting BP but not in the absolute weight lifted. Accordingly, the rise in BP with exercise, calculated as post-exercise BP minus resting BP, was invariable with the subjects. At 100%·1 RM, the rise in BP was 25 mmHg for the systolic pressure and 10 mmHg for the diastolic pressure.
(8) Difference in cardiovascular responses between the two weight-lifting forms and interpretation of post-exercise values of BP and HR are discussed.

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Sensory estimates of thermal sensation of exercising unclothed five healthy male subjects have been compared with the associated thermo-physiological responses at various ambient temperatures.
The subjects were exercising at approximately 50% of their maximal oxygen intake 30 minutes in a handmade wind tunnel. Three levels of ambient air temperatures were used at about 20°C, 25°C, and 30°C. Relative humidity was always maintained at about 60%, and the air movement was kept constant at 0.1 m/sec.
Physiological measurements were thermal sensation, skin temperatures (22 points), rectal temperature, local sweating rate and total sweating rate.
The relationship between rectal temperature and mean skin temperature and the estimate of thermal sensation was described by a summation model, where the thermal sensation was linearly related to the rectal temperature and the higher levels of mean skin temperature shifted the former relation to the higher deretion.
The subjective estimate of thermal sensation (Sense) during exercise has been described as a summation of thermal signals from the core (Tr : rectal temperature) and the skin (Ts ; mean skin temperature) as follows ;
Sense=2.21 Tr+0.29 Ts-84.81 (r=0.869, p<0.001)
Further, the linear thermal sensation-rectal temperature relationship was dependent on ambient air temperature during exercise.
Increasing the maximal oxygen intake decreased the gain of the thermal sensationrectal temperature relationship at only 30°C air temperature.
It was difficult to estimate the local sweating rate by the degree of thermal sensation during exercise.

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The present study was undertaken (1) to evaluate to what extent percent body fat predicted from commonly used equations differs from that determined by hydrostatic weighing technique, and (2) to propose sample specific equations to predict percent body fat in obese women. Subjects were 51 adult obese women (23 sedentary women and 28 active women, mostly middle-aged) . Percent body fat (% fat) determined by hydrostatic weighing (densitometry) averaged 33.1±3.7%, while % fat velues (X=27.1-30.0 in sedentary women, 24.2-27.1 in active women, and 25.4-28.4 in all women) predicted from Nagamine equations were significantly lower and correlated in the order of only 0.1 to 0.6 with densitometry %fat. Of the eight equations developed for predicting % fat of obese women, Y=8.87+ 0.223 X₁-0.180 X₂ was considered the best choice, where X₂: Katsura Index and X₂ : sub-scapular skinfold (mm) . It is recommended that this equation or some other equations developed in the present study be applicable to a wide range of adult obese women. Caution is necessary, however, as to if those equations could be generalized to younger obese women.

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