The paper describes the basics of a six-cylinder model of human thermoregulation, written in MS-FORTRAN for use on personal computers. The heat balance equations with respect to the radial coordinate, the inltial and boundary conditions, and the controller equations are explained. A complete set of parameter values is given. Emphasis is laid on the problems and status of validation. Therefore conditions and methods, on which a standard set of experimen-tal results (dynamics of 29 core, muscle, subcutaneous and skin temperatures) is based, are explained as well as possible deficiencies both of the experimental and the simulation results. It turned out that within the environmental conditions tested (15-45°C), the model, although simplifying the complex geometry of the human body to six cylinders, gives reliable results, both for steady state and dynamics of body temperature topography

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The relationship between body fat indices and cardiovascular risk was analyzed in 97 Japanese women aged 36-72 years. The variables used were anthropometric measures of body fatness, blood lipids and blood pressure. Total adipose tissue weight (TATW) was estimated from bioelectrical impedance measurements. Subcutaneous adipose tissue weight (SATW) was calculated by measuring subcutaneous fat thickness at I4 sites using a skinfold caliper. The indices of body fat distribution were the ratios of waist to hip circumference (WHR) and abdominal to hip circumference (AHR). Blood pressure and serum lipid levels were determined in all subjects after an overnight fast. The correlations among the various body fat indices were high, and all were strongly correlated with WHR and AHR ; only %SATW and percent-age internal adipose tissue weight (%TATW) were not correlated with WHR and AHR.

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The present study was designed to compare cardiorespiratory responses of swimmers to swimming and running. Six male trained college swimmers performed maximal work test (progressive method) in flume swimming and treadmill running. VEmax during swimming (128.3±20.6 l/min) was about 4 % Iower than during running (133.2±9.9 l/min). VO₂max during swimming (3628i228 ml/min) was significantly higher than during running (3408±222 ml/ min). HRmax during swimming (19l±8 beats/min) was significantly lower than during run-ning (198±6 beats/min). VO₂ at ventilatory threshold (VT) during swimming (2177±183 ml/ min) was significantly higher than during running (1699±214 ml/min). %VO₂max at VT during swimming (60.1±4.2 %) was significantly about. 10 % higher than during running (49.8±4.4 %). These results suggest that subjects of this study. have specific cardiorespiratory adaptation to swimming from a long period of swim training.

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threshold (pHT) detected by eye (E), and by regression analysis on linear (L), semilog (SL) and log-log (LL) models. Threshold for inorganic phosphate-to-phosphocreatine ratio (PT) was also examined by three regresslon analysis. Flfteen males volunteered as subjects. They performed wrist flexion in a ramp protocol of 0.14W/min till exhaustion. Throughout the exercise, ³¹P-MRS was obtained continuously from wrist flexors. Intracellular pH and phosphate compound in the muscle tissue were monitored as minute-by-minute data. In E, three observers determined pHT subjectively as a work rate just before pH decrement. In three regression analysis, pHT was detected as an intersection of a pair of linear regression lines which was selected statistically or subjectively. pHT detected by four methods showed significant re-producibility between each other, although PT did not. These results provide one of the evidences of threshold behavior of change in pH, and a question of existence of PT in contrast to pHT.

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The purpose of this study was to examine the effect of ramp slope during progressive exercise test on the intracellular pH threshold (pHT) of working muscle. To attain the purpose, we measured intracellular pH of wrist flexor by ³¹P-MRS during four kinds of ramp wrist flexion. Five Japanese males participated as subjects. They performed wrist flexion in a bore of MRS system, with ramp increments of 0.14, 0.20, 0.26 and 0.31 W/min till exhaustion. Intracellular pH of wrist flexor muscle was estimated from a chemical shift between inorganic phosphate (Pi) and phosphocreatine (PCr) on a ³¹P-MR spectra. Pi-to-PCr ratio (Pi/PCr) as an index of oxidative phosphorylation potential was also calculated. pH and PiIPCr were obtained as minute-by-minute data throughout the exercise. pHT was determined as a work rate (W) just before that at which the intracellular acidosis (acidemia) occurred. Althotigh work endurance was shortened significantly, achieved maxlmal work rate (WRmax) was increased with an increase in ramp slope. pHT both in the unit of W and %WRmax was not affected significantly by the ramp slope. On the other hand, Pi/PCr at pHT decreased with an increase in ramp slope, significantly. These results suggested that intracellular homeostasis with reference to acid-base equilibrium was not dependent on oxidative phosphorylation status, but a work output of the muscle.

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The present experiments were carried out to clarify the effects of two different kinds of shoes, i.e., the standard shoes and the mesh shoes, on thermophysiological responses and clothing microclimates (temperature and humidity) in five female students during rest and walking in the field conditions. Main results were summarized as follows : 1) Skin tempera-tures in instep, sole and leg were kept lower in the mesh shoes than in the standard shoes. 2) Rectal temperature and heart rates were also kept lo\ver in the mesh shoes than in the standard shoes. 3) Questionnaires disclosed that the subjects wearing the mesh shoes felt less damp. These findings were discussed in terms of thermal physiology. The mesh shoes seemed to be more effective for both the dry and wet heat loss from the feet to the surroundings, resulting in the inhibition of increase in the core temperature

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The effect of active recovery after intense muscular exercise was examined by ³¹P-MRS. Seven healthy males participated in this study, and their right wrist flexor muscles were examined. Each subject flexed the right wrist at 60% of the maximum voluntary contraction (MVO until the lntracellular pH in the wrist flexor muscle decreased to approximately 6.4. This was followed either by active recovery (AR) which consisted of 5, l0, 20, 30 or 40%MVC exercise, and by passive recovery (PR) during a 10-min-recovery period. The intracellular pH (pHi) recovered faster during AR at each condition than during PR. Besides, from the 2nd to the 5th min of the recovery period, the pHi was significantly higher during AR than during PR. The quadratic regression curve of pHi recovery during the 10-min-recovery-period against the %MVC was obtained. The optimal contraction intensity determined from this curve was 8.7% MVC for a 10-min-recovery-period. The optimal levels were determined for another recovery duration within 10 min, and the level decreased with the prolonged recovery duration. These data suggest that mild exercise is an effective maneuver to promote the recovery from intracellular metabolic acidosis, and that the intensity of the recovery exercise should be determined according to the cooling down duration or the resting interval before the subse-quent exercise performance.

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Threshold of decline in intracellular pH of muscle (pHT) during incremental wrist flexion was studied by ³¹P-MRS, under two levels of occlusions in which the cuff of the upper arm was inflated to systolic (ES) and diastolic blood pressure (ED), and no occlusion (E). To observe the effect of occlusion per se, intracellular pH at rest under the same two levels of occlusion was measured. Additionally, NIRS was applied to monitor the oxygenation and blood volume of the tissue during the same experimental protocol as the ³¹P-MRS study. Ten healthy Japanese males participated as subjects in the ³¹P-MRS study, and three of them in the NIRS study. They performed wrist flexion in incremental loads of 0.14 W/min ramp until voluntary

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In patients with spinal cord injury, rectal temperature is difficult to use as body temperature due to impairment such as defecation disturbance. We developed an earphone type device to measure aural canal temperature that can be also used during exerciie in patients with spinal cord injury and evaluated its usefulness. The subjects consisted of ll healthy male students. They exercised for 30 minutes using an ergometer until the heart rate increased to 150-160 bpm. Aural canal temperature, rectal tempeeature, and non-contact tympanic membrane temperature were measured before, during, and after exercise

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