hollow rock is a calisthenics exercise that primarily targets the abs ...more
hollow rock is a calisthenics exercise that primarily targets the abs.
Learning proper hollow rock form is easy with the step by step hollow rock instructions, hollow rock tips, and the instructional hollow rock technique video on this page. hollow rock is a exercise for those with a intermediate level of physical fitness and exercise experience. Watch the hollow rock video, learn how to do the hollow rock, and then be sure and browse through the hollow rock workouts on our workout plans page!