Key points to master backstroke

The fundamentals of backstroke and those of freestyle share many similarities. Both strokes are swum horizontally in the water with the body rolling on its long axis, both are asymmetrical with alternate arm stroking and alternate leg kicking, and in both, the arm pull is down the length of the body. In backstroke, however, the head is more easily controlled and does not lead to as many problems as in freestyle, and freestyle is faster because of biomechanical advantages.

There are some key points that all swimmers should focus on if you want to master that stroke. It is better if you focus on one point each time to gain the most out of each point. If you train an age-group squad you should try to mix the focus on every set (e.g. 20x50 back, change focus every 1 or 2 length).

These key points are:

1. Head steady. Swimmers should never move their head. There is no reason to look around, especially for the wall at a turn or finish. The head should be the center of stillnessand permanence, the axis that the shoulders and hips roll around. An easy breathing and stroking rhythm is created by breathing in as one arms recovers and breathing out as the other recovers.
2. Legs up, strong and steady six-beat. Swimmers should keep their bodies as horizontal and streamlined as possible, with the hips and the flutter kick close to the surface. A small and steady flutter kick helps maintain stroke control and horizontal body position. The kick should boil the water rather than splash, and the knees should stay just at the water's surface. 
3. Aggressive shoulder and pinky in. Most coaches teach a pinky-first hand entry directly ahead of the shoulder. Even more important, however, swimmers should not just set the hand into the water but should roll the hand, arm, shoulder, and hip into the water at the same time. Thus, the entry happens with the whole side of the body, not just one finger, and the entry ends at the proper catch depth, not stopping at the surface. The entry and the drive downward to the catch should be clean, strong, quick,     and one motion.
4. Wrist, rotate, and resistance. A good catch is very important to a good pull. When the swimmer has aggressively rolled to the catch depth, with the hand about 20cm (8 inches) below the surface, the arm must be repositioned to pull backward. Swimmers should press with the fingertips to cock the wrist, rotate the elbow to orient the forearm, then press backward toward the feet with the hand, forearm, and inside of the upper arm. We want swimmers to pull backstroke beside them, not underneath or behind them; the angles on the shoulder joint should be easy, not extreme.
5. Engage and squeeze the lats. The latissimus dorsi muscles of the back are much stronger than the arms. We strengthen the pull by engaging the lats to do much of the work. Swimmers pull by keeping the elbow high (that means by keeping the elbow pointed down toward the bottom) and squeezing the lats. They hang onto the water with the hand and forearm, and they keep pressing all the way to the back of the stroke, accelerating all the while. This allows the greatest impulse: force applied for the longest distance. 
6. Aggressive hip and thumb out. Just as we want swimmers to enter the water with the side of the body, we want them to exit the water with the side of the body. They should finish pushing, then simultaneously roll the hip, shoulder and hand - thumb first - vertically into recovery. The finish of the pull and start of the recovery is fast and flowing, and it takes almost no effort. 
7. Easy and relaxed recovery. The recovery arm should swing straight, relaxed, and vertical. At the end of the recovery, the hand should enter directly over the shoulder. The shoulder should be out of the water through much of the recovery so that the recovery arm doesn't plow through the water. The recovery should look and feel easy.

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