Circuit 2, Exercise 3: Single-Leg Romanian Deadlift
Hold a dumbbell in each hand (or a kettlebell in both) and lift your left foot slightly off the ground.
Keep your back flat and bend at your hips while raising your left leg, which should stay in line with your body. The dumbbells will lower toward the ground.
With your back straight, return upright, coming to your starting position. This completes one rep. Make this move harder by keeping your left foot off the ground as you go through your reps.
Continue alternating between right and left sides for 40 seconds, then take 20 seconds of rest.