Effective dolphin kicking is done with relaxed ankles which pull the water and provide a point of balance and leverage for the swimmer.

放松的踝关节是高效的海豚踢的关键，让泳者保持平衡并给予发力点。

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With good kicking technique, you can bend your knee a little on the down stroke but this shouldn't be a 'driven' movement, it's just a slight movement from a relaxed knee.

好的打腿技术，在你下压的时候膝盖稍微有些弯曲，但是并不大，只是膝盖放松的后果。

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On the other hand Russell Crowe is relaxed and kicking up his heels as Ed Hoffman, Roger's Langley supervisor and often enough "the eye in the sky, " keeping his thumb on Ferris through more of those scarily efficient satellite tracking systems we keep seeing in movies this year.

CNN: Review: 'Body of Lies' flat

But Sinfield's kicking out of hand was less accurate and the Rhinos relaxed their early grip on the game to alarming effect.

BBC: Leeds 26-36 Harlequins