Tim had a look at my stroke on Sunday. Apparently my left arm (or is it my right) swing out really wide on the recovery and I am over extending in the catch phase, wasting a lot of energy and placing unnecessary strain on my shoulder by pulling through with a straight arm.
The wide stroke, obviously contributes to drag, which I need to avoid. Narrowing my profile, making my body streamline, as if trying to thread it through the eye of a needle is the way to go. So I need to practise.
My main challenge at the moment is not over extending in the catch phase of the hand entry, but entering the water closer to my shoulder.
My stroke was much better about three years ago, but has deteriorated, possibly as a consequence of overtraining and fatigue. By over training I mean swimming excessively, often without adequate hydration, nutrition or rest. Also failing to stretch and do regular dry side exercises.
The advantage of using a high elbow catch is that it encourages better shoulder rotation, engagement of the lats and shallow pull. This keeps the body shallow, i.e. on the surface of the water as opposed to under the water and reduces drag.