This drill isolates your arms one at a time as well as an increased kick rate to maintain and support swim buoyancy. (Note may be done with or without a swim snorkel and or swim fins.)
For general propulsion and hand forearm technique
This Single Arm drill allows you to concentrate on stroke accuracy. By isolating one arm, it allows you to focus on improving technique.
Fist drill is near impossible to complete with a dropped elbow and for this reason alone is worth giving a shot. The focus is strong kick, long body and closed fists while feeling water pressure across the forearm. The drill can be completed with a tennis ball or add a snorkel, fins to embed the stroke pattern