Abstract:
:Two well-trained speed-skaters were subjected to a biomechanical analysis incorporating push-off forces, cinematographic data, and link segment modeling. To gain knowledge on the backgrounds on technique and performance in speed-skating, the muscle coordination was studied by EMG and muscle contraction velocities. In speed-skating during the push-off, the body center of gravity (cg) is accelerated with respect to the point of application of the push-off force, with a forward gliding skate. The velocity of cg is a result of rotation of segments. Due to the absence of plantar flexion of the foot, the knee extension range is limited. The short and explosive push-off can be considered as a catapult-like action. The knee extensor muscles vastus medialis and rectus femoris are prestretched in the gliding phase by the antagonistic action of gastrocnemius and biceps femoris. In this phase the skater rotates his cg from the lateral to the medial side of the skate to reach an optimal push-off angle. The power output in the push-off phase is mainly generated by the monoarticular extensor muscles gluteus maximus and vastus medialis.
journal_name
Int J Sports Medjournal_title
International journal of sports medicineauthors
de Boer RW,Cabri J,Vaes W,Clarijs JP,Hollander AP,de Groot G,van Ingen Schenau GJdoi
10.1055/s-2008-1025688subject
Has Abstractpub_date
1987-12-01 00:00:00pages
371-8issue
6eissn
0172-4622issn
1439-3964journal_volume
8pub_type
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