Wrist mobility routine I do every morning before training
The Archer Row: Your Bridge to One-Arm Pulling
If you want a one-arm pull-up and you're not training archer rows, you're missing the most direct bridge to that goal. Here's how to do them and how to progress.
Setup: hang from a bar with a wide overhand grip. Pull toward one hand while the opposite arm stays straight but provides some support. The pulling arm does the work; the assist arm provides balance and a fraction of the force.
Progression: start with the assist hand gripping the bar. Progress to gripping the wrist of the pulling arm. Progress to fingertips on the bar. Progress to holding a towel looped over the bar. Progress to hovering the hand nearby. Full one-arm is the end of this chain.
The archer row is superior to wide grip pull-ups or commando pull-ups as a one-arm prep because it specifically trains the unilateral pulling muscles in the range of motion that matters. Three sets of 5 each side, three times a week, will move the needle.