Day 85 is a spine stability card with its own set structure, printed under every exercise: 5 sets of 14 with 30 seconds rest, for each of four moves. This is not a circuit. Do all 5 sets of leg swings, then all 5 sets of alternating arm and leg raises, then all 5 sets of deadbugs, then all 5 sets of bridges, resting 30 seconds after each set. Use the timer for the rests.
Leg swings are done on all fours: one straight leg extended behind you, swinging up and lowering, 7 per leg within a set. Alternating arm and leg raises stay on all fours and reach the opposite arm and leg out at the same time, then switch, 7 per side. Deadbugs lie on the back with the arms and knees up, then lower one arm overhead and the opposite leg toward the floor, return, and switch, 7 per side. Bridges lift the hips from the floor, 14 times. Every one of the four asks the spine to stay still while the limbs move, which is what stability means, and 5 sets of each makes 280 reps of it.
On all fours, hands under the shoulders and knees under the hips, back flat. Swing the leg without letting the hips tilt. In the arm and leg raises, reach long in both directions and keep the trunk level. In the deadbug, press the lower back into the floor and lower the limbs only as far as it stays there. Bridges with the glutes, not the lower back.
Twenty sets, 280 reps and the spine never moves; that is the whole idea, and it is harder than it sounds.
Make it Harder: Slow the deadbugs to a 3-count each way and leave the other three as printed.
Make it Easier: Do 3 sets of each exercise and take 45 seconds rest.
