Start standing with both feet shoulder-width apart.
Inhale, and keep your left foot on the floor as you lift your right foot up and take a large step out to the right. Don't step out too far to the point where you lose your balance or cannot maintain an upright position with your torso. As you plant your right foot on the floor, bend your right knee, ensuring that your left leg remains straight.
From the lateral lunge position, step your right foot back in, returning to your standing position, and without touching your right foot to the ground, immediately perform four reps of high knees.
This counts as one rep.
Continue alternating performing lateral lunges with high knees on each leg, working for 40 seconds, then take 20 seconds of rest.