The objectives of this review are to delineate muscle damage induced in resistance training, discuss how muscle damage is associated with increases in strength and/or muscle cross-sectional area, and clarify whether “pain” is necessary for “gain” in muscle function and muscle volume in resistance training. Resistance training induces muscle damage, especially in the initial phase of training when unaccustomed eccentric actions are performed. Muscle damage is best indicated by loss of muscle strength and range of motion, and delayed onset muscle soreness does not necessarily reflect the magnitude of muscle damage. Resistance training employing eccentric biased exercises has potential for increasing not only eccentric strength but also isometric strength, and seems to be superior to exercise based solely on concentric actions. Since muscle damage and soreness are induced to a greater extent in eccentric muscle actions than with isometric or concentric actions, it is believed that muscle damage is necessary for size and strength gain. However, it appears that muscles become less susceptible to muscle damage as training progresses. We concluded that muscle damage and/or muscle soreness are not necessarily indispensable for exercise-induced muscle adaptation.

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The rate of increase in oxygen uptake (VO₂) at the onset of a bout of heavy exercise is faster if it is preceded by a similar bout of heavy exercise. We tested the hypothesis during heavy leg exercise that leg blood flow (LBF) and VO₂ would both be elevated during the adaptive phase. On three separate days, six healthy young men completed two bouts of 6-minutes of knee extension / flexion exercise at about 85% VO₂peak separated by 5-minutes 0-watt exercise on an electrically braked ergometer. LBF was determined by Doppler ultrasound. In the second exercise bout, LBF and VO₂ were significantly elevated in the baseline before exercise and throughout the exercise. Both the mean response time (time to 63% of difference between baseline and calculated end value) and the difference in VO₂ between minutes 3 and 6 of exercise indicated significantly faster attainment of the end exercise value in the second heavy exercise bout. These data showing the elevated LBF in the second bout of heavy exercise support the link between O₂ delivery and the adaptation of oxidative metabolism at the onset of heavy exercise.

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The effects of the Achilles tendon path change due to muscle contraction on the displacement of the myotendinous junction were determined in the human in vivo. Seven male subjects, whose knees were extended and ankles flexed at a right angle, performed isometric plantar flexion while the Achilles tendon length within the predetermined area (from the point of the myotendinous junction at rest to the calcaneus) was estimated using a high-speed camera and ultrasound apparatus. The Achilles tendon length within the predetermined area decreased by ∼1% at maximal voluntary contraction compared to the relaxed condition, which suggests that the Achilles tendon path change due to isometric contractions moves the myotendinous junction proximally by ∼1%, at the most, of the Achilles tendon length. If we simply calculate the Achilles tendon strain based on the displacement of the myotendinous junction as in previous studies, we would therefore overestimate the strain by ∼1%. This suggests that the tendon path change should be taken into account when tendon strain is calculated from myotendinous junction movements.

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No quantitative information has been reported about tibial loading during quick changes of direction (cutting) during locomotion. The purpose of the present study was to reveal quantitatively the characteristics of tibial torsional loading during zigzag running (ZR) using open-step quick cuts in comparison with straightforward running (SR). Seven adult male subjects were asked to perform SR and ZR at their maximum effort. Ground reaction force (GRF) and 3D motion data were synchronized and sampled during the course of each trial. For tibial loading analysis, net axial moments acting at both (distal and proximal) ends of the tibia were calculated using inverse dynamics. These axial moments were determined as tibial torsional moment based on the assumption that these moments matched well with each other during the stance phase of running (quasi equilibrium assumption). In the present results, the principal direction of the torsional moments seen in the ZR (external/internal rotational loading of the proximal/distal tibia) was opposite to the direction seen in the SR. The mean peak moment as well as angular impulse for the ZR was significantly larger than for the SR (28.8±8.5Nm vs 16.0±8.1Nm, P<0.05; 4.48±1.71Nms vs 1.34±0.69Nms, P<0.01). These results suggested that tibiae tend to be continuously loaded in greater torsion in the opposite direction during the stance phase of open-step cutting compared to straightforward running. Peak moments obtained from individual ZR trials could be successfully regressed with 1) the free moment of ground reaction, 2) shank transversal rotation, and 3) shank sideward tilt (R=0.838, P<0.001). The modifications of these factors would be effective for the reduction of tibial torsional loading during open-step cutting maneuvers.

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The studied muscle loss with aging, focusing on differences due to muscle group location. Muscle thickness at nine sites-forearm, upper arm anterior and posterior, abdomen, subscapular, thigh anterior and posterior, and lower leg anterior and posterior-were determined using a brightness-mode ultrasonography in 348 Japanese men aged 20 to 79 years. Only the upper arm anterior did not show a significant effect of age. For other sites, the starting age group that significantly decreased from 20-29 yr and 30-39 yr was 40-49 yr for the forearm and abdomen, 50-59 yr for the thigh anterior, 60-69 yr for the upper arm posterior, lower leg anterior and posterior, and subscapular, and 70-79 yr for the thigh posterior. The relative reduction between the 20-29 yr and 70-79 yr groups in the muscle thickness at the abdomen and thigh anterior were greater than those in the other sites. In addition, the upper arm and thigh showed a preferential loss with aging at the posterior and anterior sites. Thus, the present results indicated that the loss of muscle thickness with aging differed between body segments and between sites within the same segment. The reasons for the site-related differences in muscle loss with aging may be attributed to age-related changes in the patterns of loading to individual muscles and/or their activations, which are encountered during daily life.

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The proportion of the population over 65 has been increasing rapidly in industrialized countries. Recently, innovative devices for unconstrained monitoring of health variables at home have been developed. Previous studies focused mainly on the physical aspects, yet mood disturbances are also important in the elderly. To investigate the relationship between subjective symptoms including mood states and behavioral patterns, unconstrained monitoring of the usage of ubiquitous home appliances such as a refrigerator and a television was performed on 100 elderly people for 31 consecutive days. Using inter-event intervals for the use of the appliances, the probability density function (PDF) and cumulative distribution function (CDF) were calculated. The power-law exponents α and β were then obtained as the slopes of the linear regression in log-log plots of the PDF and CDF, respectively. Subjects with higher depression, confusion, fatigue and total mood disturbance scores had significantly smaller α and β. The more fatigued group tended to have a smaller β for the use of the refrigerator. These results suggested that the usage patterns of these ubiquitous appliances could be used to detect changes in mood states in the elderly.

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This paper discusses the culture maintenance function of playing by observing and studying as an example “the Hutterites,” which is a religious minority group trying to stay strict Christians in the contemporary North American society, and by clarifying the reason why playing, which should be basically denied, is accepted in their daily life. Playing is not denied in the strictly disciplined society, based upon a rational interpretation by the people, which regards playing as something that contributes to the enhancement of their religious mind. Even if the pleasure is something that should be denied, it is accepted as long as it serves as materials of confession at the time of baptism and leads to the reproduction of religion, like youthful deviate behavior. Even in their strict Christian life, the Hutterite people do not feel repressed by accepting playing and live a Christian life not passively but rather actively. This paper finds that the acceptance of playing is one of the reasons of the successful maintenance of their culture for more than 450 years.

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The fact that the human being develops physically from being capable of only reflex actions to being capable of versatile movement suggests that the human being is something that can be developed under specific conditions. This issue is discussed with that of “plasticity” as the ground for physical diversity from the viewpoints of physical education and sport philosophy. The most universal objective of physical education is ’physical humanization of Homo sapiens,’ its activities promote diversified human bodies by “transforming human physical forms into human bodies,” which is only possible through the medium of different forms of movement accumulated through culture. Motor capabilities that should be acquired differ with age and locality, regulated by cultural conditions. The diversity in physical abilities characteristic of human beings originates on the complex relationship between plasticity and forms of movement in a culture. Artificial and technical encouragement are vital to developing bodily structure and function and such development is not feasible without these artificial factors.

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In this paper we critically evaluate a range of scientific research that attempts to explore the issues of moral development and education in and through sport. We trace historically the theoretical roots of the research in the work of mainstream developmental psychologists Piaget, Kohlberg and Haan and articulate their attachments to different moral theories in a way that is not made clear in the sports related research. We show how their theoretical and methodological commitments necessarily alter the efficacy of the data and conclusions of the subsequent sports psychological research. In contrast, we set out an alternative moral developmental picture based on Aristotelian thought. We argue that it offers a richer picture of moral agency based on the capacities of perception, emotion and deliberation and an accommodation of the importance of the ethos or moral atmosphere of particular sporting contexts.

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Factors influential on students not positive toward physical education practice. The goal of this study is to identify factors influential on the behavior of boys and girls not positive toward physical education practice. Three categories of factors were confirmed in having influences to learning behavior of these students. Four boys and four girls in total, each one from 3rd to 6th grade elementary school students took part in our studies. They disliked physical education practice. Seventy classes were observed. Journals, interviews to teachers, and discussion with teachers are added. In addition to these, to promote studies, analysis of these data clarified that three categories of factors, that is, (1) difficulty level of motor task (2) learner group and (3) teaching principles of teachers are influential factors. These three categories had strong relation with motor skill, while they did not work positively for students, whose tendencies toward physical education is relatively low, to improve their learning behavior, and also they did not work for student motor skill to had been improved.

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The writers implemented drug abuse prevention classes, using an educational material in the form of CD-ROM. The purpose of this study was to accumulate useful data in order to help promote multimedia education as well as drug abuse prevention education. Our subjects were 204 2nd graders in 5 classes of a junior high school (consisting of 102 males and 102 females) (hereinafter called Group A), to whom lessons were given during SY1999 (February 2000) and 204 (101 males and 103 females) (hereinafter called Group B) in SY2000 (November 2000). A couple of health education teachers working in the subject school cooperatively gave the class (Team Teaching). We conducted surveys 1 week before, 1 week after, and 1 month after the class to evaluate the effect of the same with the following results: 1). The knowledge given in the class was successfully acquired by and kept well in the memory of subject students, which was shown in the increase in the number of correct answers. 2). Scores of correction for guessing also improved due to securely acquired and kept knowledge. 3). The rate of correct answers improved for all 12 items concerning knowledge. 4). Subject students evaluated favorably (positively) the material used. Accordingly, it has been proved that this CD-ROM educational material is highly and solidly effective when applied to school health education and favorably accepted by students.

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The purpose of the present study was to examine the effectiveness of weight loss program in obese women by vital age, an index to comprehensively grasp health status. Subjects were 163 obese middle-aged women and were divided into two groups: Group D (n=60) who followed a diet and Group DE (n=103) who followed both a diet and exercise in a three-month weight loss program. Results before weight loss showed that vital age of obese middle-aged women was significantly higher than the chronological age, and in accordance with weight loss, vital age became significantly younger. In Group D, the significant difference between vital age and chronological age disappeared, and in Group DE, vital age became significantly lower than the chronological age. Differences between the two groups were observed in weight, BMI, body fat, abdominal girth, SBP, VO_2LT and TG. This suggests that vital age in obese middle-aged women significantly became younger with weight loss by improving eating habits—an effect strengthened by exercise.

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The purpose of this study was to examine the characteristics of Japanese middle-aged and elderly walkers compared with sports participants. The characteristics of walkers or sports participants were defined as differences between walkers or sports participants and non-participants. A survey was conducted using a questionnaire mailed to 1,535 Japanese adults. A total of 1,047 persons replied to questionnaires, and 649 persons (222 walkers, 147 sports participants, and 280 nonparticipants) were used in analyses. Analyses were based on several factors including attitude toward physical education, sports participation in the past, and health-related items. A logistic regression analysis was applied to identify the characteristics of walkers and sports participants. Moreover, the differences between the characteristics of walkers and sports participants were examined through a comparison of characteristics. Japanese walkers tended to have a negative attitude toward physical education, be inactive during adulthood, elderly, and female. Walking will become more important in an aging society as a physical activity for people who have been alienated from such activity but are health-oriented.

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The purpose of this study was to apply the multitrait factor structure model to the control test used for the power development program for soccer players that is hierarchically constructed and to confirm contributions of the task motor skill to the test performances. Subjects were 103 male college soccer players tested on 15 items selected by qualitative characteristic attribution analysis to construct a hypothetical structure of the control test following the power training phase. Test-retest reliability of the power tests was examined. The feasibility of the multitrait factor structure model was confirmed with the structural equation modeling. It was made apparent how power and skill factors were involved in the test performance. We concluded that multiple power subdomains and multiple motor skill domains are involved in control tests consisting of multiple motor tasks. The power and skill differ in contributions in each test. There is a relationship between motor skills involved in test performance, which becomes the basis of control test arrangement.

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The purpose of this study was to analyze the relationship between changes over the years in physical abilities of young people and their exercise and sports activity statistically. Samples were 17-year-olds covered in the National Statistics on Physical Fitness and Motor Ability prepared by MEXT obtained through Sports-test during the 18 years between 1980 and 1997. Changes over the years in averages of total physical fitness test scores was statistically analyzed by gender and groups divided by participation in exercise and sports and by length of time spent in exercise and sports daily. The normal distribution curves of distance running for every 10 years between 1970 and 2000 was also visually compared, together with the effect of changes over the years and that of exercise and sports activities on total physical fitness test scores for 17-year-olds by using structural equation modeling. It was found out that total physical fitness test scores continuously decreased after 1980 for all groups divided by the participation and time spent in exercise and sports daily. It was concluded that exercise and sports activities greatly affected the yearly decrease of physical ability after 1980, especially significantly declining the systemic staying power of the group that did not participate in exercise and sports daily, and that the above was one main cause of the decreasing physical ability in Japanese youth.

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The purpose of this study was to examine the validity of System Dynamics Model (SDM) of expired gas dynamics during constant load exercise. Five healthy males conducted an incremental test to determine maximal oxygen uptake (VO₂max) and anaerobic threshold (AT). Subjects then undertook constant load tests of low intensity (80%AT), middle intensity (100%AT), and high intensity (120%AT) using a cycle ergometer. The SDM of expired gas dynamics was constructed from incremental load test data. Constant load test data was used as the validity criterion of simulation. For simulation of each intensity constant test, simulation of VO₂ and VCO2 showed significantly high determination coefficient (r²>0.7, P<.05). In the comparison of residuals of simulation, no significant differences was seen among work rate constant tests, indicating the robustness of simulation. In conclusion, the simulation of expired gas dynamics used the SD model was valid and robust to constant exercise.

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Preparation of well arranged statistical data on growth and nutrition of an ethnic group has large academic value and is vital to planning how to improve their health and nutrition. However, little data on such problems exists for ethnic groups. The author therefore propose a simple method, a growth grid method, applicable for preparing effective data indispensable to improving health and nutrition in situations where little basic data is available. We used the growth grid method to analyze health conditions of ethnic groups in Asia to better grasp their conditions.
To macroscopically evaluate the growth of children (boys) from 7 to 17 years old, the growth grid uses data on stature of 7-year-old subjects (7ys) and average stature growth of subjects per year from 7 to 17 years old to evaluate growth conditions. The method uses quadratic coordinates with two data points. All data is distributed on the quadratic coordinates of the growth grid into five groups: (A) West Eurasian ethnic groups living in West Eurasia; (B) East Asian ethnic groups living in East Asia; (C) Silk Road ethnic groups living in central Asia; (D) Tibetan heights ethnic groups living in Tibetan highlands; and (E) Southeast Asian ethnic groups spread from Southwestern China to Southeast Asia. West Eurasian peoples (A) distributed in a group spread to upper right of quadratic coordinates. Group B is situated in the lower right quarter while Group D is at the upper left quarter, and Group C is sandwiched between groups B and D. Group E are small in stature and slow in growth tempo. The growth grid proved itself feasible for practical application proving growth process are highly dependent on localities where ethnic groups live.

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Systemic arterial compliance (SAC) defining the hemodynamics for the aged can be calculated from the blood pressure waveform of the carotid artery recorded by applanation tonometry (AT). However, the recording of the waveform by AT is not easy. This study was intended to investigate the validity of evaluation method of SAC using volume clamp method (VC) at peripheral artery (finger artery). Continuous blood pressure waveform was measured using VC and AT for 47 elderly patients. Blood pressure waveform of finger artery was transformed by transfer function into waveform of brachial artery. Significant correlationship (r=0.73) between the measured values of the ratio of the area under arterial blood pressure waveform at one heart beat cycle and at left ventricular diastole by VC and AT was observed, and its agreement was good. As a consequence, validity of the method using waveform of brachial artery transformed from the blood pressure waveform recorded at peripheral artery by VC was verified as a noninvasive estimate of systemic arterial compliance for elderly people.

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Systemic arterial compliance (SAC) for the aged is a very important index in hemodynamics during exercise. In this study, the blood pressure waveform used for calculation of SAC was noninvasively recorded at finger artery by volume clamp method (VC) and compared with the method recorded by applanation tonometry (AT) at carotid artery, and usefulness and validity of this method were investigated. Continuous blood pressure waveform was recorded using VC at finger artery and AT at carotid artery during the light exercise for 22 elderly patients. The blood pressure waveform by VC was transformed by transfer function into the waveform of brachial artery. The ratio of the subjects recorded with stable waveform was 64% by AT while that of VC is 100%. Significantly high correlationship (r=0.89) between the measured values of the ratio of the area under the arterial blood pressure waveform at one heart beat cycle and at left ventricular diastole by VC and AT was observed, and its agreement was very good. As a consequence, it is supposed to be valid to use the method using blood pressure waveform recorded at peripheral artery by VC as a noninvasive estimate method of SAC for the elderly people during light exercise.

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We evaluated the effects of endurance training on systolic blood pressure (SBP) in elderly people individually, by using a single-case study design and a statistical technique, e.g., the randomization test. Six people (4 females and 2 males, 60-77 yr) participated in 12-week endurance exercise training (cycling at 80% of the work rate corresponding to the ventilatory threshold, 30-min, 5-day/wk) and recorded their own daily SBP. The mean SBP in all subjects was significantly lower than the baseline after the 7th training week (P<0.05). Individual changes in SBP with training varied among subjects. The earliest and latest occurrences of significant training effects were in the 3rd training week (-6 mmHg) and the 11th training week (-5 mmHg). In the subject who had the highest SBP at the baseline, SBP decreased 12 mmHg in the 12th training week. The subject who had the lowest SBP at the baseline (99 mmHg) did not show significant changes in SBP throughout training. We concluded that the randomization test in the single-case study design was useful to evaluate individual training effects on SBP.

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The purpose of this study was to describe the development state of motor skills by examining the achievement probabilities of the skills concerning fundamental movement-control and gymnastics that can be evaluated qualitatively. The subjects were 5,637 males and 5,064 females in elementary, junior high, and high schools. A questionnaire survey was conducted on 31 items concerning fundamental movement-control skills and gymnastic skills. The achievement probabilities and development stages of respective motor skills were reviewed by studying the obtained data. It has been found out that many of children's motor skills develop significantly while they are in elementary school. Almost all the children learn some of the fundamental movement control skills in lower grades. However, there are some among items of floor exercise and vaulting box almost all the children cannot perform, although the subject are included in the curriculum to be taught. Children need longer period of time to obtain the skill for those assignments that require strength and speed, and accordingly longer instruction period is desirable. Many of the assignments are taught after the development stage, which suggests needs for appropriate instruction periods suitable for development stages.

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The purpose of this study was to statistically analyze the changes over the years in the physical and motor ability in Japanese youth. The sample size was 12,832 boys and girls age 12 to 17 in the National Statistical Survey on Physical Fitness and Motor Ability using the Sports-test implemented for 34 years during 1964-1997. The transition trend over the years of the average by gender regarding the total scores of both of the physical fitness and motor ability tests was statistically confirmed. The first principal component score was used as the overall score in 12- to 17-year old boys and girls. The integration of 12 to 17 years old showed a significant increase for 11 years from 1964 to 1974 and a significant decrease for the following 12 years from 1986 to 1997. The both of total physical fitness and motor ability test scores of both boys and girls at the age of 17 indicated the tendency of a continuous decrease since 1985. It was concluded that physical and motor ability of Japanese youth age 12 to 17 increased until 1980 and that it tended to decrease continuously since 1985.

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Interest in flag football for teaching ball game in PE has been increasing in the last decade. Flag football is one of the few ball games in which the players have the opportunity to plan what they would do for each play. Therefore, it is more suitable teaching material for learning tactics and strategy in PE classes. However, the effectiveness of flag football as teaching materials was not clarified before.
The purpose of this study was to examine the effectiveness of flag football as teaching materials in PE classes, by analyzing the change in planning and executing strategies by children in the process of the PE unit. Concretely speaking, the change of strategy patterns which were planned and executed by children was examined in games during fifth grade and sixth grade flag football units.
As a result of this study, the following was clarified: 1) Children had planned many strategy patterns using basic tactics in flag football, and these patterns had developed only to those taking in defense into consideration. 2) The rate of executing strategies during game play increased gradually in the whole process unit.

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In this paper, Japanese traditional and folklore women's sumo is introduced as an example that female was involved in combative sport.
(1) Description in the Nihonshoki- First record of women's sumo, (2) Women's sumo as a show exhibition-from the middle of the Edo period to 1950's, there have been a women's sumo show exhibition performed, (3) Women's sumo as local folklore events and a performing art peculiar to a certain locality-in the north west part of Kyushu island (Nagasaki, Saga, Kumamoto), sumo was performed as local culture events. There are two types of sumo performed. Real sumo tournament and folklore dance as a motif without fighting a sumo wrestling, (4) Women's sumo as a praying for rain-women's sumo was performed as a praying for rain in Akita prefecture. In addition, in Okayama Prefecture and Saga prefecture, there are records that women's sumo was performed for praying rain, (5) God sumo in Okinawa-at the time of festival called Shinugu and Unjami, festival praying for abundant crop (fertility), sumo tournament of man against woman was performed in Okinawa. As above-mentioned, Japanese sumo was not exclusive to the male. Women was said to have participated time to time in the sumo tournament.

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The purpose of this study was to verify the relationship of the occurrence of low body temperature at rising time and intraday body temperature changes, rising time, going-to-bed time, exercise hours, heart rate at rising time, and intrinsic motivation for attending school at rising time. The subjects, 452 healthy junior and senior high school male students, were divided into two groups, namely, Average group (AG) with an axillary temperature above 36.0 and below 37.0 at rising time and Low group (LG) with an axillary temperature below 36.0. The temperature was taken on a weekday without physical exercise classes in school in June 1999 and in the same month in 2001. The level of intraday body temperature of LG was lower than that of AG. The body temperature of AG reached its peak around noon, but that of LG peaked around 4 o'clock in the afternoon. The body temperature at going-to-bed time of LG did not get lower to the level at rising time. The heart rate of LG (66.6±9.0 beat · min^-1) was significantly lower than that of AG (70.9±10.7 beat · min^-1). The intrinsic motivation for attending school of LG (3.0±1.1 points) was significantly lower than that of AG (3.6±1.2 points). Those with the above motivation in LG (36.6%) were significantly smaller in number than those in AG (54.4%). The students with an axillary temperature below 36.0 at rising time were found to have characteristically lower level of intraday body temperature, showing the highest at around 4 o'clock in the afternoon. Also their going-to-bed time temperature did not go lower to the level of rising time. Furthermore, their heart rate was low at rising time and they were low in the intrinsic motivation for attending school at rising time.

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