今天又去Y跟高教练游泳，先还是打水400米。高教练指出脚不够“内八字”。练完后被
表扬比以前好多了，并且膝关节和踝关节也比较放松了。
今天游泳的收获有两点：
1。二次打水的kick发力应该和push一起，我发力早了点儿，刚开始pull就发力了。
2。手入水后就开始往下收腕，避免over-glide从而造成掉肘。这点跟swim smooth里讲
的“smooth”type一样。
（Smooths may appear to glide at the front of the stroke but this is not the
case when swimming properly. When viewed from under the water their hands
are always in motion - either extending forwards, tipping the fingertips
downwards or commencing the catch. This much higher skill level is a
critical difference from the Overglider type.） http://www.swimtypes.com/smooth.html
