The purpose of this study was to compare the direction of kick movement during front crawl at different swimming velocities. Eight competitive national-level male swimmers with a specialty in front crawl participated in this study. They performed the front crawl at two different swimming velocities-maximum velocity (V100%) and 80% of the velocity of the their respective best times for a 100 m front crawl (V80%). The trials were recorded with four underwater digital video cameras. One stroke cycle, between two consecutive right-hand entries, was analyzed. Downbeat kick movement was quantified using an index of kick pattern (IKP). The following results were observed.
1) There was no significant difference in the vertical width of the kick movement between V100% and V80%.
2) There was a significant difference in the horizontal width of the kick movement between V100% and V80% because of an increase in the hip roll angle.
3) The IKP was dependent on the horizontal width.
4) The kick movement was confirmed to have an overall vertical direction at V100%.
5) The kick movement was confirmed to have an obliquely downward direction at V80%. These results indicated different directions of the kick movement during front crawl at different swimming velocities.

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The present study explores whether interventions such as target hitting play and horizontal-bar play effectively promote the development of orientation and differentiation abilities related to the throwing motion in children aged from 4 to 4.5 years and those from 4.5 to 5 years. Tests were performed before and after the study period to verify the effectiveness of these motor play interventions.
The effectiveness of target hitting play was examined in group A; this playwas effective in boys as they developed orientation ability for moving objects at 4 to 4.5 years of age and differentiation ability for balls of different weights at 4.5 to 5 years of age. The effectiveness of both target hitting play and horizontal-bar play was examined in group B; these proved effective for girls from 4 to 4.5years of age. Horizontal-bar play particularly contributed to the development of orientation and differentiation abilities. From the above results, the effect of each motor play issuggested to be different at different times depending on gender; therefore, it will be more effective when it is performed at the appropriate time. In particular, it was revealed that that orientation and differentiation abilities do not develop simultaneously in boys.

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It has been reported that females are more likely than males to complain of feeling chills. As such, it may be important to study these physical symptoms, and the severity and causes thereof, within segments of the female population, such as junior college students, as this may contribute to improving their health. Seeking to perform such research, this study examined the relationship between female students’ chill sensations and factors such as physical characteristics, diet experience, and sports experience.
A comparison of the chill complaint rate between students with a BMI of less than 18.5 and those with a BMI of 22.0 or more revealed that slim students tended to experience a higher rate of chills than students with a higher than average body weight.
Next a similar comparison was conducted between dieting students and non-dieting students, and this revealed that those who were on a diet at the time had a significantly higher chill complaint rate (5% significance level) compared to those who were not.
Ninety-two (20.5%) of the students reported that they were engaging in sport/exercise approximately once or twice a week, while 357 (79.5%) said that they were not. Despite this large contrast, however, these were no significant difference found in the chill complaint rate between the two groups.
Of the 123 students who stated that they were members of an athletic club during junior high school or high school, 65 (52.8%) were in the low chill sensation score group. In contrast of the 102 students who were not affiliated with an exercise club during junior high school or high school, just 42 (41.2%) were in the low chill sensation score group. Hence, no clear association was found between chill sensation and participation in sports/exercise during junior high or high school.
In light of the above findings, it can be considered that providing guidance on improving eating habits, including dietary advice, might help reduce the number of female youth who feel chills.

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The purpose of this study was to compare the direction of kick movement during front crawl at different swimming velocities. Eight competitive national-level male swimmers with a specialty in front crawl participated in this study. They performed the front crawl at two different swimming velocities-maximum velocity (V100%) and 80% of the velocity of the their respective best times for a 100 m front crawl (V80%). The trials were recorded with four underwater digital video cameras. One stroke cycle, between two consecutive right-hand entries, was analyzed. Downbeat kick movement was quantified using an index of kick pattern (IKP). The following results were observed.
1) There was no significant difference in the vertical width of the kick movement between V100% and V80%.
2) There was a significant difference in the horizontal width of the kick movement between V100% and V80% because of an increase in the hip roll angle.
3) The IKP was dependent on the horizontal width.
4) The kick movement was confirmed to have an overall vertical direction at V100%.
5) The kick movement was confirmed to have an obliquely downward direction at V80%. These results indicated different directions of the kick movement during front crawl at different swimming velocities.

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