The purpose of this study was to determine the feasibility of estimating myocardial oxygen supply/demand relationship noninvasively for the evaluation of myocardial stress during arm and leg exercises. Seven healthy males performed arm cranking exercise (ARM) and leg cycle exercise (LEG) at each of four constant power outputs (ARM : 5,10,15,20 W, LEG :25,50,75,10O W). Electrocardiogram, phonocardiogram, carotid pulse wave and blood pressure were simultaneously recorded during the exercises. The pressure of cardiac cycle was estimated by substituting systolic blood pressure (SBP) for peak of carotid pulse wave and diastolic blood pressure (DBP) for base line of that, respectively. Potential subendcardial blood flow was also estimated from the Diastolic Pressure Time Index (DPTI) and myocardial oxygen requirments were estimated from the Tension Time Index (TTI) , respectively. The ratio DPTI/TTI, thus, provided an estimate of myocardial oxygen supply/demand relationship. Results indicated that heart rate (HR) and SBP increased more steeply in relation to work rate during ARM than LEG (HR : 1.53vs.0.41bpm・W^&lt-1&gt, SBP : 1.64vs.0.368mmHg・&lt-1&gt, p&lt0.01).Consequently,TTI increased linearly with the work rate both durirg ARM and LEG ; this increase was, however, significantly higher for ARM than LEG,i. e., TTI was higher for ARM at maximum work rate (20W) than LEG at minimum work rate (25W) (3020vs.2300mmHg・sec・min&lt-1&gt, p&lt0.01).The rate of decrease of DPTI/TTI per work rate during ARM was also significantly(p&lt0.05)greater than LEG. These results suggested that arm exercise in comparison to leg exercise is accompanied by not only higher myocardial oxygen demand but also greater myocardial stress caused by an unfavorable shift in the balance of myocardial oxygen supply and demand. Based upon these results, it seems that DPTI, TTI and DPTI/TTI determined by the noninvasive method employed in the present study may provide an effective index to the measurement of myocardial stress in various type of exercise.

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This study clarified the specificity of leg strength and power in several sport athletes. To accomplish this purpose, a new physical fitness test was developed to evaluate the capacity for the ballistic and stretch-shortening cycle (SSC) movements. 1. The drop jump (DJ), a typical SSC movement was used in this test. A few experiments were performed to determine the best dropping height and jumping technique of DJ in 10 college male athletes. These results showed the best method of DJ was rebound DJ with small angular displacement of the knee from 0.3 m beause of appearing the shortest contact time and the longest air time, and being ballistic and safe movement. 2. Average force[F_&ltindex&gt ={(t_a)/2 + (2・h_d/g)^&lt1/2&gt}/(t_c + 1)], average Power[P_&ltindex&gt ={g・(t_a/2)^2 - 2・h_d}/ (2・t_c)]and the capacity to jump higher within shorter contact time[DJ_&ltindex&gt = (1/8・g・t_a^2) /t_c]are calculated by using contact time (t_c) , air time (t_a) and dropping height (h_d) of DJ, and g (9.81 m/s^2). Interrelationships between DJ_&ltindex&gt F_&ltindex&gt, P_&ltindex&gt t_c and t_a were examined in 93 male athletes of 14 sport events. These results showed the best index was DJ_&ltindex&gt because of reflecting both F_&ltindex&gt and P_&ltindex&gt, and t_c and t_a. 3. The specificity of leg strength and power was investigated by comparing with DJ_&ltindex&gt height of counter movement jump (CMJ-H) and maximum strength exerted by squat posture at 90°of knee angle (S-MAX) in 93 male athletes of 14 sport events. This result showed all sport athletes were grouped into A, B and C type. Jumper and sprinter, gymnast and kendo atheletes belonged to A type which showed the character of large in order of DJ_&ltindex&gt, CMJ-H and S-MAX. Skater, ski jumper and swimmer belonged to B type which showed contrary character of A type. Ball game player and long distance runner belonged to C type which did not show difference among them. But excellent players for jump and footwork in ball games showed the same character as jumper and sprinter. These results lead to the conclusion that we should evaluate not only the general leg strength and power but also the capacity for the ballistic and SSC movement by measuring DJ_&ltindex&gt when coaches scout for sport talents and athletes practice the training according to specificity of strength and power. It should also be added that DJ_&ltindex&gt is a practical index which can be simply and exactly measured by using matswitch.

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Managers in commercial sport clubs must develop efficient marketing programs for their target market. This necessitates the managers to collect and analyze the information about the behavior of program participants, i. e. consumer behavior. This paper is intended to examine consumer preferences among sport participants. A case study approach was taken to focus upon choice decision process among commercial sport club users. Analyses were made to investigate club users' trade-offs between sets of service attributes. Conjoint analysis was applied in this process. Conjoint models represent a decompositional approach for predicting individunl's preferences for the stimulus object as a whole. The data for this study were collected in urban commercical sport clubs located in Osaka. A sample of 198 club members were studied through computer interactive interviewing. Six service attributes and 18 levels were considered in the study design. Service profiles which were combinations of the attributes and levels were presented to respondents by means of paired comparisons. The overall ranked data were analyzed using Johnson's nonmetric tradeoff algorithm. The use of conjoint analysis allows the researcher to determine consumer's part-worth utilities for each service attribute under study. In addition, consumers are segmented on the basis of attribute importance in order to enhance the analysis. The findings of the case study include : distance and augmented facilities were more influencial factors to users' preferences than membership fee and instructor quality. Membership initiation fee and business hour were not very important. The results of segmentation suggest that `distance' segment and `augmented facilities' segment represent relatively large subsets of the club user market. It can be concluded, from what has been found in the study, that conjoint analysis is a powerful and useful technique for analyzing consumer preferences in the commercial sport club maket.

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This study was designed to analyze the jumping forehand smash of elite players based on three-dimensional kinematic data, and to get insight into the basic badminton smash technique. Jumping smashes of four male elite players were filmed with two high speed camears operating at 250 frames per sec with exposure time of 1/1500 and 1/1250 sec. The nine jumping smashes were selected for the analysis, and were digitized from the take-off of the jump to the end of the swing in the air. Thirty three-dimensional coordinates for the segment endpoints and racket were computed by a Direct Linear Transformation Method. Small reference poles were fixed on the forearm of the swing arm of the subjects to detect their movements of the radio-ulnar joint and wrist joint. Following six joint angle changes were obtained throughout the smash motion. (a) pronation/supination angle at the radio-ulnar joint. (b) radial flexion/ulnar flexion angle at the wrist joint. (c) palmar flexion/dorsi flexion angle at the wrist joint. The resultd showed that pronation of the radio-ulnar joint seemed to contribute to produce great velocities of the racket head, because the rotation occurred the greatest range in the shortest time in the three rotations immediately before contact with the shuttle. Preliminary to the motions were motions in the opposite direction; e. g., supination of the forearm was detected. These motions in the opposite direction would be useful to extend the range of the motion in each joiot angle. The order of time of the last joint rotation starting immediately before contact was ulnar flexion, palmar flexion and pronation. Respective times required for the rotation until contact became shorter in turn of late occurring. The faster the rotation was, the later the rotation occurred and the shorter the rotation time was. This kind of chain and continuous movements of different joints, and different freedom in the same joint may accelerate the racket head efficiently. The averages of the racket angle (the angle between the forearm and racket shaft) was 147.0゜at the contact.

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