Many swimmers are under the impression they should complete the back of the freestyle stroke with a big push as the hand passes the hip. You can reduce your strokes per length doing this but over-emphasising the push can cause swimmers numerous problems:
- It tends to fling your hand out of the water by your hip giving an unbalanced arm recovery action. Not only does this harm your rhythm but it can also cause you to snake which creates lots of drag.
- When emphasising the push, many swimmers push upwards not backwards, this is wasted effort and can act to sink the legs down, again increasing drag.
- Locking out your elbow by pushing hard causes a delay in the stroke timing. Since your other arm is extended forwards at this point it naturally causes a dead-spot at the front end too. Dead-spots harm your efficiency because you decelerate and then have to re-accelerate on the next stroke. In other words, over-emphasising the back of the stroke can harm your efficiency by turning you into an overglider.
- The amount of extra propulsion you gain is really quite small and it's inefficient because it overloads the small tricep muscles. The effort required is normally too high to sustain for more than a few laps. Swimming is quite deceptive in this regard, things that feel easy for 25m can quickly become unsustainable beyond 100m.
If you watch elite swimmers racing, you'll see that they don't complete each stroke with a distinct push and they don't lock out their elbows straight. In fact, they normally finish the back of the stroke with a distinctly bent elbow. Here's a nice clip of Ian Thorpe showing this: www.youtube.com/watch?v=-8egC7PbOME
Great swimmers like Ian finish their stroke naturally as a consequence of their body rotation and stroke timing. We suggest you target the same thing: work on your catch, stroke timing and rhythm, and the back of the stroke will follow and naturally click into place when everything else is right. When you find this natural timing you gain speed and efficiency - it's the cause of the 'sweet spots' you can find with our ramp test.