With a partner:
Isometric squat hold
Hold squat position below parallel with good posture for the duration of your partner’s 5 Inchworm. Immediately upon completion, switch roles. Count rounds completed in 10 minutes.
One partner holds the hollow position while the other partner waits.
As soon as the position breaks, other partner starts. Goal here is as few rounds as possible, and to accumulate more time in the hollow than your partner during the 10 minute clock.