Day 17 puts the upper body back in the circuit: 20 overhead punches, 20 shoulder taps, 20 punches, 20 overhead punches and 20 thigh taps, in order, for 3, 4 or 5 sets with up to 2 minutes rest. The shoulder taps are the plank version from Day 5. Thigh taps are new and also in a plank: from a straight-arm plank, one hand reaches back to tap the same-side thigh and returns to the floor, 20 in total, alternating hands.
Overhead punches open and reappear in the middle, so the vertical drive of the shoulders is the theme of the day, with the straight punches in between changing the angle. The two plank exercises look similar and load differently: tapping the opposite shoulder reaches across the body, while tapping your own thigh reaches back and down, which shifts more weight onto the supporting arm and asks the hips to stay level through a longer reach. Both are there to take the shoulders from moving fast to holding still under load and back again within the same set.
Overhead punches drive from the guard to full extension above the head, alternating arms, with the ribs kept down rather than arched. Straight punches keep the Day 5 standard: full extension, hip rotation, hands straight back to the chin. In the thigh taps, keep the feet a little wider for balance, the hips square and the supporting arm locked; the hand touches the thigh and comes straight back - no pause, no lean.
Forty overhead punches per set and the plank taps have moved from shoulder to thigh - Day 17 is Day 5 with new coordinates.
Make it Harder: Bring the feet together for both plank exercises and keep the hips motionless through every tap.
Make it Easier: Cut both plank exercises to 10 taps and keep all three punching exercises at 20.
