Isometric contractions occur when a muscle generates force without changing its length. This type of contraction happens when you push against an immovable object or hold a position, like a plank. The muscle fibers are activated, but there is no visible movement in the joint. These contractions are important for maintaining posture and stability. They can also help improve muscle strength and endurance. Common examples include holding a weight in place or pressing against a wall. Isometric exercises are often used in rehabilitation and strength training programs to enhance muscle performance without straining the joints.