Effects of playing sports together on the physical competence of children with and without disabilities
The present study examined whether the physical competence of children with and without disabilities could be improved if they participated in a sports activity program intended for children to enjoy soccer together, regardless of disabilities. The participants included nine children with intellectual disabilities enrolled in a special support class and 12 children without intellectual disabilities enrolled in a standard class. A questionnaire survey of the children’s physical competence was conducted before and after their participation (pre and post) in the soccer games. ANOVA was performed on the athletic ability scale scores using a linear mixed model of group (children with disabilities and children without disabilities) × time (pre and post). The interaction of the feeling of control, one of the subscales of the questionnaire, was marginally significant. The simple main effect test following the Bonferroni method showed that, on the pre-participation questionnaire, the scores of the children with disabilities were significantly lower than those of the children without disabilities. However, the post-participation scores of the children with disabilities were significantly higher than their pre-participation scores. These results suggest that the feeling of control of children with disabilities may improve so as to be at par with that of children without disabilities when children with disabilities participate in a team sports activity involving children with and without disabilities.
Health-related quality of life and body composition of long-term judoka
The present study examined whether the long-term practice of judo is associated with maintenance of and improvement in health, specifically the quality of life (QOL) and health condition of individuals who had practiced judo for a long time. Their quality of life was assessed through questionnaires, and their health, through measurements of their body composition. Two surveys of judoka who had practiced judo for long time resulted in 250 usable quality of life questionnaires. In addition, the body composition measurement survey resulted in useable data from 323 respondents. Analysis of the data showed that the health-related quality of life of long-term judoka was higher than the national standard value. A comparison of the participants’ health-related quality of life by age, years of experience as a judoka, and training frequency revealed that the health-related quality of life in the older respondents, those with more years of experience, and those with a greater frequency of training was significantly higher. Analysis of the body composition measures of these long-term judo practitioners indicated that their fat free mass index (FFMI) and body mass index (BMI) were higher than had been reported in previous studies, and their fat mass index (FMI) was unchanged. Previous studies had suggested that because a high lean body mass is associated with maintaining and improving health, long-term judo practitioners must have healthy bodies. The results from the present study suggest that these long-term judo practitioners were healthy. It is possible that life-long practice of judo may to contribute maintaining and improving individuals’ health.
Comparison of kinematics and muscle activity in prone and dorsal underwater dolphin kicks
The purpose of the present study was to examine differences in kinematics and muscle activity between prone and dorsal underwater dolphin kicks. The participants, 8 male collegiate swimmers, performed trials in which they did 15-m underwater dolphin kick swims in the prone and dorsal positions at maximum effort. During the swim trials, 2-D motion analysis was conducted, and surface electromyography (EMG) was measured from 8 muscles in each swimmer’s trunk, thigh, and lower leg in order to obtain data for kinematic and muscle activity analyses. No significant differences were found in average swimming speed, kick frequency, kick amplitude, or Strouhal number between the two kick positions. However, the range of motion of the shoulder joint and the maximum angle of plantar flexion of the ankles were significantly larger, and the range of motion in the trunk was significantly smaller when the participants swam in the dorsal position than when in the prone position. In addition, although no significant difference was found in muscle activity pattern between the two positions, the average EMG of the rectus abdominis and external oblique muscles was significantly higher in the dorsal position than in the prone position. These results suggest that in dorsal underwater dolphin kicks, the upper limbs should be pushed down by the shoulder and hip joints during upward kicking, and the abdominal muscles should be more active during downward kicking.
Effects of different steps when driving forward on athletic performance in basketball
The present study examined effects on basketball players’ performance of differences in stepping movements and the direction of a player’s drive, under a total of four conditions: driving to the left or right combined with stepping with open steps or cross steps. The participants were ten male university basketball players. A pole resembling a defender was placed in front of a participant, and the participant was instructed to dodge the defender (the pole) and drive forward, either to the left or to the right. An optical 3D motion analyzer and force plates measuring the force on the floor were used to analyze the participants’ movements. The participants’ performance was evaluated from their reaction time, the speed of their movements, the driving force of their axial leg, and the angle of rotation of their body. The results were as follows: (a) no significant difference was found in reaction time between the two types of stepping movements when the participants were driving forward, (b) cross steps were associated with significantly faster movement when the participants were passing by the side of the pole, perhaps because cross steps provide a greater propulsive force than open steps, (c) differences between the two stepping movements affected the angle of rotation of the body, and (d) the angle of rotation was greater when the participants used open steps than when they used cross steps.
Relationship between type of movement in high-speed skips exercises and sprinting performances
The present study examined a high-speed skips exercise that is generally considered to be an effective training method for improving sprinting performances. The participants were 34 university male students who were majoring in physical education. An observational method was used to evaluate their movements when doing high-speed skips. The movements were classified into patterns to clarify their objective features and the relationship of the high-speed skipping movements and sprinting performances. Latent class analysis was used to classify the participants’ high-speed skips movements into 3 categories according to a standard developed for evaluating these movements. In this evaluation, the greater the number of total points given to the participants’ movements, the faster the speed and the stronger the ground reaction force of their high-speed skips movements. An analysis of the relationship between the participants’ high-speed skips movements and their performances in the sprint confirmed that their sprinting speed differed among the categories of high-speed skips movements. In addition, the spatiotemporal variables, including speed, were significantly correlated with each other. These results suggest that sprinting speed may be improved through an understanding of movement types in the high-speed skips exercise.
Judging under-rotation in figure skating: university figure skaters' understanding of the scoring rules
The scoring of jumps in figure skating is determined from a combination of points for technical difficulty and for quality. If a jump is judged to be under-rotated, points are generally deducted from both of those scores. The standards for judging a jump to be under-rotated are defined in the official competition rules. Seminars on the rules are provided for coaches, but not for skaters. Further, the present authors were unable to find any published investigation of skaters’ understanding of judges’ scoring standards. The present study compared university skate club members’ judgments of under-rotations to judgments made in actual competitions, using videos of competitions that had been broadcast. The results suggested that the university skaters’ judgments tended to be more lenient than the ones made by the competition judges. For the analysis, the participants (N=22) were divided into two groups at the median. The scoring by the skaters who had had more coaching corresponded more closely to that of the competition judges than did the scoring by the skaters who had had less coaching. This may be a result of the skaters having had very limited opportunities to learn the standard scoring criteria on their own. In order for skaters to be able to evaluate their own performance and improve their technique, it may be necessary to establish a system in which judges and skaters can come to a common understanding of the scoring standards.
Effects of leg position on kick start performance: considering leg strength
In the kick start, swimmers put one foot on the front edge of the starting block, and the other foot on the back plate. The present study compared effects of competitive swimmers’ foot position on their kick start performance, specifically on whether their stronger leg was placed in the front or the rear. College swimmers (12 male, 4 female) performed 4 kick starts, alternately using their preferred and non-preferred combination of front and rear foot positions. A Biodex System 3™ was used to measure the isometric maximal voluntary contraction of the extension of both of the swimmers’ knees, in order to determine which was the stronger leg. Other measures analyzed were start parameters, that is, the take-off horizontal and vertical svelocities and the take-off angle. The take-off velocity and the horizontal take-off velocities with the stronger leg on the front edge of the starting block were significantly higher than with the weaker leg in that position. These results suggest that positioning the stronger leg in front may improve kick-start performance.