Start standing with your feet together and your arms at your sides. Pull your core in toward your spine, and keep your chest lifted.
Lift your right leg and bend it, bringing your knee into your chest with control. Clasp your hands around your knee or shin to hug it as close to your chest as you can.
Set your right leg back down, and repeat on your left leg.
This counts as one rep. Continue alternating legs for 30 seconds while maintaining proper form.