A wall sit is an isometric exercise that targets the muscles of the lower body, particularly the quadriceps, hamstrings, and glutes. To perform a wall sit, you lean against a wall with your back flat and slide down until your knees are bent at a 90-degree angle, as if sitting in an invisible chair. Hold this position for a set duration, typically ranging from 20 seconds to several minutes. This exercise is beneficial for building endurance and strength in the legs without requiring any equipment. Wall sits can be easily modified for different fitness levels by adjusting the duration or adding variations, such as lifting one leg or holding weights.