Air
Finger-to-Shoulder Recruitment Hysteresis
On your back, arms by your sides, start the smallest possible oscillation in the right hand — a finger curl-uncurl at maybe two cycles per second. Locate the exact frequency at which each joint snaps into the wave, and notice whether you can drop back below that threshold...
Full Lesson Notes
Complete Practice
On your back, arms by your sides, start the smallest possible oscillation in the right hand — a finger curl-uncurl at maybe two cycles per second. Slowly accelerate. Somewhere the wrist will begin to participate involuntarily, then the elbow, then the shoulder; this is the body's own tacking-through-the-wind moment, where momentum from the small driver carries the larger limb across a force-free crossover. Locate the exact frequency at which each joint snaps into the wave, and notice whether you can drop back below that threshold without the larger joint disengaging. Hysteresis is the question — does each joint engage and disengage at the same frequency?
