TAKAGI Hideki UNIVERSITY OF TSUKUBA, ASSISTANT PROFESSOR, 体育科学系, 講師 (80226753)
MATSUI Atsunori NARUTO UNIV.OF EDUCATION, ASSOCIATE PROFESSOR, 学校教育学部, 助教授 (40190384)
TAJIKA Hidetsugu AICHI UNIVERSITY OF EDUCATION, PROFESSOR, 教育学部, 教授 (30109368)
OHGI Yuji KEIO UNIVERSITY, ASSISTANT PROFESSOR, 環境情報学部, 講師 (90317313)
Lyttle et al (1999) suggested that the efficient glide depth around 0.4m and streaming will result in an increased glide distance. On the other hand, Takagi and Sanders (2000) has shown that swimmers must consider the optimal depth of glide following the turn around 0.35-0.45m. It has also been pointed out that further analysis of the turn and gliding should incorporate new methods and ideas (Lyttle, A et al., 1999, Goya.T., et al., 2000, 2001). However there is little information about training effects in gliding for novice swimmers. Therefore, It is quite interesting whether novice swimmers can attain a stream-lined position and where they pass through underwater displacement by a given glide swim training.
The purpose of this study is 1) to investigate how the swimmer should acquire the stream-lined position before, during and after push-off phase, by using a digital video camera system connected to an under-water force plate, 2) to clarify the optimal depth for stream-lined position considering with locus of center of gravity.
As a result, In teaching glide swimming, we should focus on a streamlined position and kick off direction before kick off the wall. This means that if the swimmer fails to assume the appropriate streamlined position, this will cause a great deal of frontal resistance at this point in the motion. This finding is supported by fluid dynamic study (Lyttle, 1999) that it might be beneficial for swimmers to perform their gliding at underwater around 0.4-0.6m to reduce wave and vortex drag efficiently. Therefore, It could be suggested that more efficient depth of center of gravity and streaming would result in an increased glide distance.