Stand with feet hip-width apart, holding one weight in right hand with arms by sides. Jump right foot to right, bending left leg and crossing it behind right to land in a deep lunge with right knee bent 90 degrees and on ball of left foot, weight outside right leg to start.
Immediately jump left foot to left as you draw weight across body in an arc, passing it to left hand at the midpoint.
Bend right leg and cross it behind left to land in a deep lunge with left leg bent and on ball of right foot, weight outside left leg. Switch sides; repeat. Continue, quickly alternating sides for 30 seconds.