This is a drill that can be done with a tool (shovel knife …) or with your fists and feet. Start by placing your arms so they create fists that do not fall back on your body (reverse vector of the strike is not towards you and the equal force counter wave doesn’t hit you) and have people either strike you with a staff or with their body and you have to stay tensed up enough to maintain this form in the upper body as you use the lower body to survive the attacks and hit back. After you do this several times with several positions for the arms reverse the tension chain and have your legs rigid and your upper body free to redirect and work to survive (start this by being on the ground and working the upper body arms and all to survive people working to strike and wrestle with you)
Learn to move effectively by starting to move from the body first and use all that you have even though the tension.