The subject of the thesis was to find a link between the following variables: take-off of a ski jumper on a ski jumping hill and during an imitation of a take-off. We also studied the structure of take-off power of a ski jumper in a squat.
The research was carried out in May 2017 on a sample of 18 Slovenian ski jumping competitors who had different success rates in the previous season. The research sample included 4 female ski jumpers.
The measurements were made using a tensiometer (SP sport MP4-1, Austria) and a force gauge (Imada Z series, HTG2, DTX2). Force gauge helped us measure the isometric force in a ski jumping squat. With the help of tensiometer we measured the vertical power of the take-off in an imitation of a ski jumper’s take-off. First task consisted of the execution of vertical take-off, second task was imitating the take-off with catching and third was to imitate the take-off on a special machine called Planica 2. Firstly, the task was measured with ski jumpers wearing sports shoes and secondly with them wearing ski jumping shoes.
The research showed that using the Planica 2 device the power measured with force gauge decreases with the increase of the lever. Average height of the take-off was higher with vertical take-off (M = 45 cm) than with take-off with catching (M = 42,9 cm). When performing a take-off on the Planica 2 device some ski jumpers experienced trouble with the take-off technique. The number of ski jumpers who performed the take-off correctly was 9 when wearing sports shoes and only 7 when wearing ski jumping shoes. The average height of the take-off wearing sports shoes was significantly higher (M = 46,4 cm) than the average height of the take-off when wearing ski jumping shoes. (M = 27,5 cm). The height of the take-off in ski jumping shoes significantly decreased mostly due to the fact that the chosen ski jumpers lacked sufficient practice of the take-off in ski jumping shoes. Another factor that caused the low result is the limitation of the ankle extension during a take-off when wearing ski jumping shoes. Extension of the joint is much bigger when wearing sports shoes, therefore the impulse of the vertical force of the take-off is higher as well.
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