Take a look at Sun Yang’s high elbow in the under water pull phase. Look at how he pushes off on his back at the wall during a turn and rotates to his front in a streamlined position, keeping his head down for that first stroke. How he rotates to his side and really holds the water. As this is a 1500m swim his kicking is not as fast as it would be if he were swimming 100m, however it is still great technique kicking from his hips.