The purpose of the present study was to assess the effect of commercial sports beverage intake after a thermal exposure on water-electrolytes balance.
Nine healthy male volunteers with a mean age of 26.4 years, not heat acclimated, participated in a control experiment where no fluid was given (C experiment) . Five of them were given 500ml isotonic sports beverage containing Na⁺, K⁺, Cl^-and glucose (S. B experiment) and/or 500 ml tap water (Wa experiment) immediately after sauna exposure. The nude subjects were exposed to a sauna with 65 to 70°C (r. h. 50 to 60%) for 30 min.
Serum protein, electrolytes (Na⁺, K⁺, Cl^-), creatinine, plasma aldosterone (Ald), and catecholamines concentrations and excretions of electrolytes and aldosterone into urine were measured before, and 3, 30, 60, and 120 min after the sauna. Serum and urinary osmolalities, blood pressure, rectal temperature (Tr), heart rate, oxygen consumption and weight loss were also measured.
Body weight loss ranged from 50 to 750g. Serum protein, electrolytes and Ald concentrations increased significantly after the sauna. The enhanced levels of these variables and the depression of urine volume, urinary Na⁺excretion were maintained throughout the 2h recovery period in C experiment. Hydration associated with a reduced concentration of serum protein and electrolytes was observed at 30 min in S. B, at 60 min in Wa, and a dehydration occured again at 120 min both in S. B and Wa. A peak of urine volume was observed at 60 min in S. B and at 120 min in Wa during recovery. Free water clearance (C_H2O) was -0.98 ml/min/100 ml GFR (Ccr) prior to the exposure. With no fluid administration after the sauna, an excess in negative water balance remained throughout the 2 h recovery. But C_H2Ochanged from negative to positive at 60 and 120 min after sports beverage and/or water loadings.
A significant elevation of % TRNa (0.33 to 1.14%) was maintained after the sauna in both C and Wa experiment. Plasma Aid concentration and excretion of Aid in urine after the exposure were higher in both C and Wa than in S. B experiment. The increased Tr did not return to the initial level throughout the recovery. No significant differences were observed among the three experiments in heart rate and blood pressure as well as Tr.
The data indicate that salt deficit due to the sauna exposure was attenuated, but not prevented, by sports beverage intake, although the Aid secretion was alleviated. It is suggested that an over loading of sports beverage or water (i. e. 500 ml VS 50 to 750 g weight loss) leads to a marked and prompt water-diuresis, and to another dehydration. The increase of Tr as well as a partly salt deficit can be related to the rises in Ald secretion still observed at 2 h recovery.

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The rucksack paralysis is currently considered to be caused by the compression or hypertraction of brachial plexus or long thoracic nerve. However, its precise mechanism has not yet been fully clarified. In the present study, we attempted to explain the mechanisms of rucksack paralysis. For this purpose, three sets of studies were performed, i. e., (1) examinations on the exact localization of shoulder straps with the aid of radiographic analysis, (2) measurements of the compression under the straps with load cell, strain gauge and prescale, and (3) anatomical studies on the nerve pathway under the compressed area.
In the experiments with six male and five female subjects, the inside edge of the strap at rest was found to run from area around the center of clavicle to the lateral side of the ribs. Finally, it went down to the inner part of the axilla. However, on tread-mill walking the position of the strap's inside edge shifted to the lateral part of the clavicle and that of the central part moved to both the acromion of the scapula and the head of the humerus. Thus, during the actual walking with rucksack, the strap was considered to move within these areas. In addition, we found that carrying a rucksack displaced the scapulae toward the median.
From measurements of the compression under the strap with six male subjects, the following common findings were obtained: (1) the heaviest load was upon the upper part of the body trunk, i. e., suprascapular region (4 subjects) and clavicular region (2 subjects), and (2) the edge of the strap produced stronger compression than its center did.
Anatomical studies with ten cadavers revealed that the brachial plexus might be strongly compressed in the case of muscular hypertonicity or body surface compression.
The long thoracic nerve arised from the branches of the 5 th, 6 th and 7 th cervical nerve. Joined nerve trunks of the branches of the 5 th and 6 th cervical nerves frequently appeared at the lateral side of the brachial plexus. The branch of the 7 th cervical nerve joined with the nerve trunks running through the middle scalene muscle, although location of this nerve conjoining was somewhat different among various cases, i, e., at the proximal side of the second rib in seven cases and at the area between the 2 nd and 3 rd ribs in three cases. The long thoracic nerve was found to turn downwards at the second rib, and this turning point was located at the tuberosity of the serratus anterior muscle.
From these results, we consider that the paralysis of the brachial plexus is caused by the load of rucksack working as a tractive external force on the nerves between the clavicle and neck, while it acts as a compressive external force on the nerves from coracoid processes to the axillary region. On the other hand, the paralysis of the long thoracic nerve seems to occur due to hypertraction of or compression over the tuberosity of the serratus anterior muscle of the second rib.

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Thirteen female swimmers (ranging in age from 15 to 18 years) were selected as subjects and divided into two groups; group A (subjects of experiment) consisted of six subjects in whom low pressure was loaded and group B (subjects of control) consisted of seven in whom low pressure was not given.
During training, circuit weight training was performed in a low pressure environment and it was combined with conventional swimming training. We studied the effect of these types of training on their red-cell 2, 3-diphosphoglycerate, salivary cortisol, and plasma testosterone.
(1) The 2, 3-DPG level showed a greater increase after loading exercise than at the time of resting in both groups A and B. The increase was highly significant in group A. Additionally, 10 days after the removal of the loading, hemoglobin and hematocrit levels were significantly decreased in groups A and B, and a significant increase in 2, 3-DPG was observed in group A.
(2) Only after loading low pressure was the cortisol level higher in group A than in group B. However, there was no significant difference between the two groups in the amount of exercise loading when heart rate was used as the index.
(3) Testosterone tended to show a greater increase after exercise loading than on the first day of the experiment. However, neither an effect of exposure to low pressure on testosterone nor a significant difference between the two groups was observed.
According to the results, in swimming, an endurance contest, physical changes during training are almost the same in group A and B, but it is considered that a concurrent severe hypoxic condition as a result of low pressure loading brings about homeostasis in the living body and the homeostasis leads to an attempt to increase oxygen uptake by the tissues, yeilding increased staying power.

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Male rats were trained to escape from radiant heat of infrared lamp (250W) by pressing a bar that turned a lamp off for 8 sec. To determine effects of repetitive exercise on this heat-escape behavior rats were either subjected to a 4-week physical training program in which they were forced to swim in agitating water of 36t or 38°C for 1 hour each day or were not trained (non-exercised controls) . After the program in 36°C water, the bar-pressing rate during the test period decreased markedly compared with that before the training period. Temperatures of the tail-skin and the environment in the test box increased to significantly higher levels in the trained rats than those before the training period, while the rectal temperature in the trained rats remained at the same level to that in the pretraining period. When a 4-week physical training program was completed in the same manner but using 38t water, no differences in the heat-escape activity and the extents of temperatures concurrently measured were obtained between those before and after the training period in the trained rats or controls.
The significant reduction of heat-escape activity in rats with the repetitive exercise for 4-week in the 36t water is a result of adaptive changes in the autonomic thermoregulation due to the repetitive exercise itself.

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The purpose of the present study was to determine whetehr differences exist between nine experimental conditions mixing 10°, 40°and 70°of hip joint angles with knee joint angles, when thirteen subjects performed the same response task. In the experiment 1, each subject was asked to stand on the inside two of the four mat switches (500×700 mm) and keep the assigned joint angles during a second of preparatory period. After the period, each subject was asked to respond with a step out on either the right or the left outside mat switch as quickly as possible. Then the data was collected analyzing the whole body choice response time (RESPONSE TIME) defined as the interval time from the signal to respond with step out, the whole body choice reaction time (REACTION TIME) defined as the interval time from the signal to reaction with lifting the leg for responding to the step out, and the movement time (MOVEMENT TIME) defined as the interval time subtracting RESPONSE TIME from REACTION TIME. Moreover, in the experiment 2, the data was collected and analyzed from the onset time of various forces from the two force platforms on which each subject stood instead of the mat switch and EMG which was led from the right side of m. rectus femoris, m, biceps femoris, m. gastrocnemius, m. tibialis anterior and the left side of m. quardriceps femoris, during performance of the response task. The results were as follows:
1. The subjects' posture with each 70°flexion of the hip and the knee joint revealed the shortest RESPONSE TIME, because of the shortened MOVEMNT TIME, compared with the other posture. Conversely, the posture with 70° flexion of the knee joint showed an expanded REACTION TIME.
2. The knee joint angle was an important factor effecting both REACTION TIME and MOVEMENT TIME, rather than the hip joint angle for the task of the experiment, since flexion of the knee joint expanded the REACTION TIME, but shortened the MOVEMENT TIME.
3. The result of the force platform measurements indicated that the posture with each 70°flexion of the hip and the knee joint was shorter than that with each 10°flexion of them at the onset time of the first reaction force after the reaction signal, and that the order of response for the task was beginning at the leg for responding, followed by the other leg for keeping stability.
4. Conclusive evidence for a shortened RESPONSE TIME was found in the facilitation of the central nervous system, which revealed the preliminary muscle activity and the stabilizing of the posture.

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Study on the sites of nerve entrance in innervation of skeletal muscles is important in the field of anatomy, histology, physiology and pathology, and since 19 th century, many researchers have been engaged in the macroscopical investigations on nerve entrance of muscles. However, their results were not always precise, because they seemed to employ macroscopical methods without measuring a length of muscles and a distance between origin and insertion of various muscles in thigh
In this paper, first, the muscle length was determined by measuring the distance between origin and insertion directly (designated here as“direct method”) or by measuring the length of muscles along their course (designated here as“indirect method”) by scale. Concomitantly, the number and diameter of major innervated nerves of each muscle were also examined. Next, the distance between nerve entrance and the origin of 9 thigh muscles were carefully measured. The difference of the values obtained referring to sex and age was also surveyed. Adding to it, the correlation between the sites of nerve entrance and that of muscle belly was also studied. The details of respite were ae fn11imr
1) The values of muscle length obtained from direct and indirect methods were compared in paying attention to each belly of muscles. 10 specimens in M, sartorius and M, rectus femoris were used for it. The difference of values between direct and indirect methods was negligible, that is, only 1 to 2.5% difference are there respectively.
2) The number of major nerve entering into each muscle were one or two. The number of major nerves and their diameter (parenthesized) of 21 specimens were as follow; one (1.6 mm) for M, sartorius, two (1.6 mm) for M. rectus femoris, two (2.4 mm) for M, vastus medialis and M. vastus lateralis, one (1.8 mm) for M, gracilis, one (1.7 mm) for M. adductor longus, two (2.4 mm) for M, biceps femoris (caput longum), two (2.5 mm) for M, semitendinosus and two (2.6 mm) for M, semimembranosus.
3) Using 41 specimens, the sites of nerve entrance where one or two major nerves were entered into thigh muscles were measured with the indirect methods. The sites of nerve entrance were indicated with the ratio calculated from the formula described in Result-C. Their sites were 21.4% from the origin for M, sartorius, 14.9% and 25.5% for M. rectus femoris, 22.6% and 39.3% for M. vastus medialis, 17.0% and 35.1% for M, vastus lateralis, 22.3% for M, gracilis, 44.7% for M, adductor longus, 22.1% and 38.6% for M. biceps femoris (caput longum), 15.5% and 43.0% for M. semitendinosus, and 46.7% and 61.7% for M, semimembranosus. However, the difference in the sites of nerve entrance related to sex and age was hardly in those specimens.
4) The difference between the sites of nerve entrance (either one or two) and muscle belly was evident in M, vastus medialis and M, adductor longus. The values of deviation in M. vastus medialis and M. adductor longus stood about at 20%. The difference of the other muscles (M. sartorius, M, rectus femoris, M, vastus lateralis, M, gracilis, M, biceps femoris; caput longum, M, semitendinosus, M, semimembranosus) stood at 3 to 7%.
5) Some discussions were devoted to the relationship of sites between nerve entrance in anatomy and motor point in kinesiology.

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This study was performed to investigate the optimal frequency of jogging in order to prescribe a jogging to myself as the subject. The program of jogging training was composed of two parts; I) jogging about 4 km 4 days a week for 12.5 years (having started from age of 50 years old), and then stop jogging for about 6 weeks, and II) jogging once a 5 days for 1 year. Blood pressure, blood components and the frequency of arrhythmias appearance were measured and discussed.
After 4 years from starting jogging at age of 50 years old, ventricular premature contraction (VPC) was observed, and then after 10 years VPC, including multifocal VPC, couplets and 3 consecutive VPC was observed frequently, especially after jogging. Therefore, jogging was stopped for about 6 weeks. In 2 nd part of jogging, no arrhythmias appeared in jogging once a 5 days. The recordings of blood pressure and blood components were normal and exercise-induced stress by a low frequency of jogging didn't increase.
Consequently it should be suitable to prescribe a jogging once a 5 days to myself.

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