Day 10 numbers its exercises as four moves and runs them in order without a break. Move 1 is a 10-count plank hold on your hands. Move 2 is 10 alternating arm and leg raises from that same position, lifting one arm and the opposite leg together. Move 3 is 10 plank rotations, turning from the plank into a side plank with the top arm reaching straight up to the ceiling. Move 4 is 10 climber taps, driving a knee forward under the body and reaching the opposite hand down to tap it. Rest up to two minutes at the end and repeat.
The sequence is a single position getting progressively harder to keep. The opening hold sets the line and switches everything on. The arm and leg raise takes two of your four points of contact away, so the hips have to resist tipping in two directions at once. The rotation opens the body to the side and hands the load to the obliques, then returns it. The climber taps close by making the base move underneath you while a hand leaves the floor to meet a knee. Every move asks the same question - can you hold the plank while something else is happening - and each one raises the stakes.
Set your hands directly under your shoulders and keep them there. In the arm and leg raise, go slowly and lift only as high as you can without the hips rolling open; a small stable reach beats a big wobbling one. On plank rotations, turn as one piece and let your eyes follow the reaching hand up. For climber taps, keep the hips low and level - the temptation is to pike upward to make room for the knee, which takes the abs straight out of the equation.
Four moves, one position, and your shoulders will complain before your abs do.
Make it Harder: Pause at the top of every plank rotation for a two-count with the arm vertical before turning back down.
Make it Easier: Skip the reach in the plank rotations - turn to the side plank with the top hand resting on your hip and come back.
