|Function:||Leg Ext (Vertical)|
Position progressively higher plyo boxes in series spaced apart with room to jump between each box. Stand in front of first box with narrower than shoulder width stance.
Jump to first box landing with both feet, drop to floor then immediately jump to next box. Repeat jumping from floor to next box until last box is reached.
Plyo boxes can be of same height or of progressive heights arranged from lowest to highest. Greater box heights decrease ground reaction time. Unless box heights are 12" (30 cm) or less, step off of edges of each box instead of jumping up and off of boxes. If boxes are deep, land on box, then step to far end of box before stepping off.
Spine is kept straight during jump push off and jumping up to short boxes. However spine flexes when legs are pulled up onto taller boxes. Consequently, spine also extends just before final landing.