Squats, and lunges, and the best one, find a heavy weight
, lay on your back, feet flat on the floor close together, put the weight
on your hips
, then clench your butt together as hard as you can and raise your butt in the air. It should like like you are slowly thrusting the air, and once you get tired, you want to increase the intensity by doing at least 20 more fast thrusts.