Complete the arm stroke underwater during the freestyle (push phase) all the way to the thigh before exiting the hand, in order to maximize propulsion, save energy, and smooth out the aerial recovery of the arm.

noli's read

The science of biomechanics fully validates this coaching advice. In freestyle, the arm cycle ends with an underwater push phase that is too often cut short by amateur swimmers. A kinematic study published by researchers from the University of Edinburgh in the journal *Research Quarterly for Exercise and Sport* (2024) demonstrates, however, that this final push is one of the fastest and most propulsive phases of the arm cycle. By shortening this gesture, one decreases their stroke length (the distance traveled per movement). Yet, the synthesis work of biomechanics expert H. M. Toussaint establishes that this length is a direct reflection of propulsive efficiency, which is crucial for conserving energy in a natural environment. Finally, accelerating the hand toward the hip generates valuable inertia which, according to consensus guides from reference organizations such as *Swim England*, greatly facilitates a fluid and relaxed arm recovery.

the sources

No named source held this one up — that absence is part of the verdict.