While sumo wrestlers aren't known for their lean physique, this squat will definitely help sculpt your legs for shorts season. Be prepared to feel your inner thighs burning the next day!
How to do it: Stand with your feet wider than hip-width apart, toes slightly turned out, holding a medicine ball in front of your chest. Squat down as low as you can, keeping your heels on the ground and your back straight. Press back up to standing. That's one rep. Do 15 reps total.
You can use a dumbbell or a sandbag instead of a medicine ball if you don't have one.