Are you aware of how your arm enters the water when you swim?
Can you hear noise, bubbles and turbulence?
Most swimmers have been taught to reach; to swing the arm around the body and enter the water high and flat.
In most cases, this will assist a hip drop at the back end and increase drag – and we don’t want that!
Efficient freestyle hand entry
The hand should enter the water smoothly. Imagine a mailbox slot, next to your head. Slide your fingers in, followed by hand, wrist, forearm; they follow the yellow line demonstrated in the pics below, to the ‘catch’ position.
Read this TI blog post on the benefits of a good ‘catch’.