|Too much knee bend||1. Revise basic drills.
2. Concentrate on a small flip of the feet.
|Lack of undulation in the body||1. Practice dolphin kick under water.
2. Practice dolphin kick under water arms extended above head.
3. Start the action by moving the head.
|Only one kick per stroke||1. Kick and glide when the hands enter the water.
2. Reduce the glide later.
|Straight arm pull||1. Learn 'keyhole' pull.
2. Scull with hands (out, in, out).
|Arms fail to recover clear of water||1. Practice over short distances to avoid fatigue.
2. Breathe by poking the chin forward close to the surface.
3. Recover the arms wide (thumbs down).
|Timing||1. De-emphasize kick. focus on 'head enters water before hands, head lifts before hands exit water'.|