Butt kickers: 1 minute
Rev up your run and kick your heels up towards your glutes, pumping your arms back and forth as quickly as you can for 60 seconds [as shown].
Single-leg squats: 1 minute
This sculpting move helps develop balance while toning your legs (and is better than using a leg press machine). Stand on your right leg, left foot flexed and lifted a few inches off the floor, hands behind your head. Push your hips back and bend your right knee to lower into squat [as shown]. Extend your right leg to return to standing, keeping left foot lifted the entire time. Repeat as many times as you can for 30 seconds, then switch legs.