Day 10 is the cleanest plank day in the program. Four front holds, 30 seconds each: a wide plank, an elbow plank, a standard plank and another elbow plank. No side work, no lifted legs, nothing to balance - just your body in a straight line, four times, at two different heights.
Alternating between hands and forearms is not decoration. On your hands, the shoulders and chest carry a meaningful share of the load and the position sits higher, which lets the core work with slightly better leverage. Down on the forearms, the hips drop closer to the ground and the lever between your elbows and your toes lengthens, which shifts the demand squarely onto the abs and the lower back. Switching back and forth means neither height gets to become comfortable, and by the fourth panel the drop to the elbows feels less like a change of position and more like a change of weight. The wide stance opens the card because a broader base is the easiest version, and the standard plank in third place is the moment it stops being easy.
Keep the same standard in all four: hands or elbows under the shoulders, glutes tight, ribs pulled down so the lower back does not dip, and eyes on the floor just ahead of your fingers. Breathe steadily rather than holding your breath and bracing - a plank you breathe through is a plank you can finish. If the hips start to rise into a tent shape, that is the core buying itself a rest; bring them back down and hold the line honestly.
Four planks, two heights, zero movement - the purest version of what this program does.
Make it Harder: Press your toes together and squeeze thighs and glutes hard for the full two minutes; a plank held under total tension is a different exercise entirely.
Make it Easier: Drop your knees to the floor for the two elbow planks and keep the line from knees to head straight.
