[Objective] The aim of this investigation was to evaluate serum steroid hormone responses to acute resistance exercise. [Methods] Subjects were young healthy males (n=6) and females (n=6) . Each group performed three sets of 10 leg press and 10 bench press exercises at an intensity of their individual 10-repetition maximum (1ORM), with 1 min rest between sets. Blood samples were collected before (Pre-Ex) and immediately following the exercise (P0), 30 mm (P30), 60 mm (P60), and 24 hours (P24h) after the exercise. Levels of blood lactate, serum testosterone, dehydroepian drosterone sulfate (DHEAS) and cortisol were determined. [Results] The levels of blood lactate in males and females significantly increased at P0 and P30 compared with Pre-Ex (p<0.05) . In males, the serum level of testosterone significantly increased at PO (p<0.05), whereas in females, it significantly decreased at P0, P30, P60, P 24 h. (p<0.05) . The level of DHEAS significantly increased at P0 in both males and females (p<0.05) . [Conclusion] The change in the level of testosterone was different between males and females, but that of DHEAS showed a similar pattern for both sexes. The data suggest that DHEAS could be a useful indicator for evaluating the anabolic status of acute resistance exercise in females.

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The mechanism of the latent reaction time in task completion in elderly men was investigated by comparing the reaction time (RT), EMG-RT and motor time (MT) in young and elderly men. The motor performance was recorded as task completion through as a WS-RS, simple reaction or a choice reaction for each movement using a handgrip and switch.
In this study, we found that the RT and EMG-RT of elderly men in all movements of WS-RS and choice reaction tasks were significantly longer than those of young men, especially in the choice reaction tasks were striking. Moreover, the MT of elderly men in all tasks was significantly longer than those of young men.
These findings suggest that the latent RT and EMG-RT in a choice reaction task may be due to relayed information processing through as the discrimination and cognition functions in the brain, and that it may be also influenced by the mechanism of the latent reaction time of task completion in elderly men.

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The purpose of this study was to determine the influence of a 6-month unsupervised, flexible and fairly light intensity walking program on endurance fitness, strength, lipids and lipoproteins and bone health in a group of middle-aged sedentary women. Six pre-menopausal and 8 post-menopausal women, aged 54 yr, served as the walk training group (W) and 9 women (2 post-menopausal), aged 49yr, served as controls (C) . W walked an average of 10, 000 steps per day for 6 months, which included an average of 5, 000 steps of brisk walking for 30 min, 4 to 5 days per week. Workloads, heart rates and double-product break point (during incremental maximal ergometer exercise), body weight and %fat, serum lipids, leg strength and bone density (by ultrasound) and induces of bone metabolism were measured at baseline and after 3 and 6 months. Walk training in W resulted in a significant improvement in maximal workload during the exercise test compared with C. Double product break point in W during exercise significantly shifted towards higher workloads and resting heart rate was reduced. Isokinetic muscular strength of leg extensors and abdominal muscular endurance measured by situps were also significantly increased in W. Estimated calcaneal bone density showed a tendency to increase after 6 months of training in W. Indicators of bone resorption and growth remained unchanged. Changes in serum lipids and lipoproteins were also favorable, but not significant. In conclusion, these results show that a flexible and self-regulated walking program is sufficient to elicit improvements in cardiovascular endurance, aerobic capacity measured by DPBP and strength of leg and abdominal muscles. Bone strength and serum lipids were not clearly improved after 6 months with this walking program. If training time were extended to 12 months, significant improvements in these measures can be expected because tendencies toward improvements were observed.

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Although the precise mechanisms underlying the dysfunction of sarcoplasmic reticulum (SR) that occurs during skeletal muscle fatigue remain obscure, it has been hypothesized that it may be attributable to oxidation of critical sulfhydryl groups residing in SR Ca²⁺-ATPase protein by endogenously produced reactive oxygen species. In order to test this hypothesis, SR Ca²⁺-ATPase activities in the absence or presence of the disulfide reducing agent, dithiothreitol (DTT), were examined in muscle homogenates of the soleus muscles (SQL) and the superficial portions of the vastus lateralis muscles (VS) from the rat subjected to exhaustive running at 50 m/min on a 10% grade. Immediately after exercise, the catalytic activity of SR Ca²⁺-ATPase was significantly depressed in VS, but not in SQL. The loss of SR Ca²⁺-ATPase activity observed in VS was fully recovered after treatment with DTT (1 mM) . These recovery effects of a potent disulfide reducing agent suggest that important proteins of SR Ca²⁺-ATPase may be oxidized during high-intensity exercise and that the onset of muscular fatigue may be delayed by the improved function of the cellular antioxidant

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Purpose: The purpose of this study was to examine the relationship among helmet surface temperature (Thl), head top temperature (Thd) and tympanic temperature (Tty) during American football practice in summer. Methods : The subjects were collegiate American football players. Temperatures were measured in August in 1993 and 1994. Thl, Thd and Tty were measured by infrared tympanic thermometers. Environmental temperatures that were measured were dry-bulb temperature (Td), wet-bulb temperature (Tw), globe temperature (GT) and wet-bulb globe temperature (WBGT) . Results: Significant correlations were observed among all measured temperatures (P<0.0001) . High coefficients of correlation were observed among Thl, Thd and GT. The highest relationships were observed between Thl and Thd (r=.727), and between Tty and Td (r=.766) . The coefficient of correlation between Tty and Thl was higher than that between Tty and Thd. Heat stress of the whole body (F1; heat stress factor: Tty, Td, Tw and WBGT, proportion=71.4%) and head environment factor (F2 ; helmet factor : Thl, Thd and GT, proportion=14.3%) were chosen in factor analysis. A close relationship was observed between both factors (r=.773) . Both GT and Thl showed a high correlation with Thd, which suggests the influence of radiant heat through a helmet on the whole body. Conclusion : The temperature in a helmet is a micro environment temperature surrounding the head. Accordingly, the heat load is reduced by taking the helmet off frequently during football practice.

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Previous research has demonstrated that the concentric muscle strength of knee extension exerted at slow to medium angular velocities is increased by teeth clenching. This study evaluated the isokinetic eccentric strength of knee extensors at 4 angular velocities (60, 120, 180 and 240 degrees per second) with and without teeth clenching on the Cybex 6000 Extremity Testing and Rehabilitation System. Twelve healthy adult male (26.8±1.8 years) volunteered for the study. Peak torque per body weight and average power per body weight were analyzed. The results demonstrated that peak torque per body weight accompanied by teeth clenching was significantly increased at 60, 120, 180 and 240 deg/s by 9.5%, 8.2%, 8.2% and 9.8%, respectively (p<0.01) . Similarly average power per body weight during teeth clenching was significantly higher at 60, 120, 180 and 240 deg/s by 9.1%, 9.5%, 9.4% and 7.7%, respectively (p<0.05) . These findings suggest that teeth clenching is a factor that leads to augmented eccentric strength of knee extensors. Its effect appears to be independent of angular velocity.

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The purpose of this study was to examine the validity of physical performance tests (test battery) for assessing functional fitness required for activities of daily life in older persons with chronic disease. This test battery consisted of 4 items: arm curl, walking around two cones, moving beans with chopsticks, and functional reach. Seventy-one persons (aged 66.7±7.8 yr) with either hemiplegia, Parkinson's disease (PD), or chronic obstructive pulmonary disease (COPD) served as subjects. There were significant differences among standard test scores in each rate of progression of the disease in all hemiplegia groups (Stages III, IV, V), and COPD groups (Stages 1, 2, 3) (Kruskal-Wallis'H=22.3 and 7.3, respectively) . In PD groups, there was no significant difference between standard scores in Stages II and III (Mann-Whitney's U=4.0) . However, the rank order correlation coefficient between the ranking in standard test score and the ranking in physical independence assessed by a medical doctor and a public health nurse was significant (ρ=0.57, P<0.05) . All tests were safely applied for all subjects. These results suggest that our test battery may be applicable to a majority of older persons with various chronic diseases. Furthermore, the variability of standard test scores was greater than the clinical subjective ratings by Stage, which suggests that such a classification may provide a better description of disease progress/functional fitness.

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The present paper focuses on the leaking enzyme, PGAM (phosphoglycerate mutase), which is attracting increasing interest among medical researchers, and its relations with physical exercise. As a preliminary, purified PGAM-B was extracted from erythrocyte. First of all, erythrocytes were burst by hypotonic buffer. The contents were let through DEAE-Sepharose column and then through an affinity column bound with PGAM antibody. The purified substance thus obtained is analyzed by SDS-PAGE and has been found only in the single band of approximately 30 kDa. It has been injected to a mouse to develop its antibody. The mouse antibody thus developed and commercial anti r-h-PGAM-B rabbit antibody have been used to in order to perform double antibody sandwich ELISA on PGAM-B. R-h-PGAM-B was used as a standard substance. It has been observed that our standard curve shows a linearity in the range of 0-100ng/100μl, with R²=0.9849. The correla-tion between intensity of physical training and PGAM-B concentration in serum has been analyzed. Non-athlete male students, long distance male and female runners took part in the experiment. The sera of the male runners were found to have 34 times higher PGAM-B concentration than those of the non-athletes. The male runners had 3.6 times higher concentration than those of female runners. Non-athletes ran 10 km and their serum PGAM-B concentration were measured afterwards. It was found that concentration was 3.2 times higher after the run than before it, and this increasing found in all subjects.

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