This is due to the feet being strapped into the board and both feet pointing in the same direction, which localizes knee movement and prevents twisting.

这是因为脚被钻进了董事会和双脚指向同一方向，膝盖运动的本地化，防止扭曲。

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Young female long jump two levels of athletes instantaneous and take off in the process in the board to swing the leg knee Angle oversized folds not tightly.

少年女子跳远二级运动员在着板瞬间和起跳过程中摆动腿膝角过大，折叠不紧。

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The take-off leg knee joint, hip joint Angle when they get to the board and the most keen Angle in the take-off process are all smaller than those of high level female long jumpers.

少年女子跳远运动员在着板瞬间的起跳腿膝角、起跳腿髋角、以及起跳过程中起跳腿的最大屈膝角都小于高水平女子跳远运动员。

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One piece of good news for Bangladesh is the return of seam bowler Mashrafe Mortaza, who missed the tour to New Zealand because of knee problems and illness but played for a Bangladesh Cricket Board XI against England on Thursday, bowling eight wicketless overs at a cost of 48 runs.

BBC: Mohammad Ashraful

The England Cricket Board said that Pietersen first felt some pain in the knee during fielding practice before the start of the Test series this month, confirming speculation that he had not been completely healthy at the beginning of the tour.

WSJ: Pietersen Quits Tour With Knee Injury

As a board-certified plastic surgeon, I can legally perform a knee replacement or hysterectomy, procedures for which I am completely unqualified.

CNN: Plastic surgery: 'Wild West' of medicine