Reebok master trainer Sara Haley designed this series to burn fat and sculpt and tone the upper body. Pair these moves with either your lower-body strengtheners or cardio routine (or both!), depending on your Week 3 daily schedule. And if you feel sore the next day? Take it easy, not off. "Consistency is key," Haley says.

For this first move, begin in plank position. Lower yourself, then push back up, bringing right knee toward left shoulder (next image). Repeat, switching legs. Do 8 to 12 reps.

Start in a squat with a flat back, arms at sides with thumbs to ceiling (no weights this week). Lift arms straight out to sides, forming a T, squeezing shoulder blades. Lift arms, pressing shoulders away from ears to form a Y. Do 10 to 15 reps.

Elevate upper body on chair or bench with arms straight, elbows soft. Stretch legs out long, balancing on heels. Keeping glutes and core engaged, lower body by bending elbows, keeping shoulders away from ears (next image). Hold for 2 counts and push back up. Remember to breathe. Repeat 10 to 15 times.

Using a set of 3- or 5-pound weights (or full water bottles), press palms to the back of the room, squeezing shoulder blades together. Rotating thumbs to ceiling, raise straight arms up on an angle, no higher than your head (next image). Do 20 reps.