[header] How to do a marching plank [title] Start with a forearm plank. [step] This is what most people consider to be the standard plank exercise, and it's a good place to start if you want to master the plank itself before moving on to more challenging variations. [substeps] You can get into position either by starting on all fours or by laying face down on a mat. 
Line your elbows under your shoulders so that your upper body is supported by your forearms, and extend your legs behind you so that you are on your toes. Your body should be a straight line from your heels to the crown of your head.