This exercise builds strength in the quadriceps, core, glutes, and upper body. Doing single-leg exercises like this improves balance and stability, as well as dynamic flexibility in the knee, ankle, and hip joints.
How to do it: Grab a pair of dumbbells and stand tall, holding the weights by your sides. Take a big step out into a lunge. Bend both knees, keeping front knee directly above ankle. Drive off the ball of your big toe to come up in a standing position. Keep your foot off the ground as you curl the dumbbells up toward your shoulders. Keep elbows fixed in place. Continue by stepping the foot that is lifted forward into a lunge. Do 10 reps on each leg.