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发帖数: 1389 | 1 to create a topspin you don't have to hit the top of the ball.
most of spins ( top, side, back) come from off-center hit. for example, when
you're serving a topspin, your racket moves mostly up-forwards before it
reaches the highest point when your arm and racket are straight in line,
therefore, the force transmitted to ball will be up-forward. forward force
gives the pace, upward one brings the topspin. sure, during contact the ball
sinks into the springbed,springs bite the ball and give it ext |
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