Boldly, Go! is a lower body workout on a five-year mission through your quads and glutes. Four blocks of lunges chart the course, with calf raises and two rounds of twenty scissor chops between them - a voyage that keeps returning to the same demanding territory just when your legs think they have seen the last of it.

The recurring lunge is the warp core of the whole operation. Four blocks of six reps distribute twenty-four quality lunges across each set, and the spacing is the strategy: every block arrives after just enough diversion for your legs to recover their form but not their comfort. The exercises in between are not downtime. Calf raises keep the work in the lower body while shifting it below the knee, and the scissor chops - arms sweeping horizontally across the body at speed - load the shoulders and chest with high-rep endurance work while your heart rate stays up from the lunges. It is a full away team: legs lead, arms and calves provide support, nobody stays on the ship.

Step boldly into each lunge - a confident stride, back knee dropping straight down, front shin vertical. Push through the front heel to return. Keep the scissor chops crisp and at shoulder height for all twenty; drooping arms are the first sign of a crew losing discipline. Rise to full height on every calf raise rather than bouncing through them.

Space may be the final frontier, but the fourth block of lunges runs a close second. Engage.

Make it Harder: Add a knee drive at the top of every lunge.

Make it Easier: Cut the scissor chops to ten and shorten your lunge stride.