The wall sit is a simple yet effective exercise that targets the muscles in the thighs, hips, and core. To perform a wall sit, find a flat wall and stand with your back against it. Slide down until your knees are at a 90-degree angle, as if sitting in an invisible chair. Hold this position for a set amount of time, typically starting with 20 to 30 seconds. This exercise is beneficial for building endurance and strength in the lower body. It requires no equipment and can be done anywhere, making it a convenient option for those looking to enhance their fitness routine.