Day 2 turns the workout into running in place. The circuit is 20 high knees, 20 march steps, 20 high knees and 20 butt kicks - one straight pass for a set, 2 minutes rest, 3, 5 or 7 sets by level. Nothing moves sideways today; it is all forward-facing leg drive, at two speeds.
High knees are a run on the spot with the knees driven up toward hip height, arms pumping, one knee per rep. They are the fastest way in this program to get the heart rate up, and they open and return in this circuit for exactly that reason. Between them, march steps are the same movement with the flight removed - a high-knee march, one foot always on the ground - which brings the intensity down without letting the legs stop, so the second block of high knees arrives with the heart still elevated. Butt kicks finish: running in place with the heels kicking up toward the glutes instead of the knees coming up in front, arms relaxed at your sides. Same run, opposite leg action, and it moves the effort from the hip flexors to the hamstrings for the last 20 reps.
Drive the knees properly high in the high knees - if the thighs are not reaching parallel, slow down until they do. Keep the march steps tall and unhurried; they are the recovery in the circuit. On butt kicks, stay light on the forefoot and let the heels really touch or nearly touch the glutes; if they are only coming halfway up, you are jogging, not kicking.
Run, march, run, kick - twenty days from now this circuit will feel like a warm-up, and today it counts as the workout.
Make it Harder: Speed up both high knee blocks until 20 reps take under 15 seconds, and keep the knees at hip height at that pace.
Make it Easier: Do the high knees as march steps too, so the whole circuit is marching and butt kicks with no flight phase.
