Feet in the straps, saw your body back and forth.
Keep your hips level and braced, the smaller the saw the harder the burn.
The bodysaw takes a forearm plank and adds slow horizontal drift, your feet gliding in the straps while your abs fight the growing lever arm every centimetre you slide back. Nothing bends, the entire challenge is anti-extension, your core refusing to let the lower back arch as your shoulders push away. It deserves a spot as one of the smartest plank progressions there is, because a few centimetres of saw multiply the demand without adding a single second to the set.
A plank is static, the bodysaw moves the load away from your base, so your core has to work harder at the far end of every rep. You get plank benefits plus a real progression path.
Only as far as you can go with zero arch in your lower back. Most people overreach, a small controlled saw with a rigid trunk beats a big sloppy one every time.
Almost always ribs flaring and hips dipping as you slide back. Tuck your pelvis slightly, brace before you move, and shorten the range until you can own it.
