1. Concentric Strength. In a concentric contraction the muscles shorten and produce movement. Concentric strength is sometimes known as overcoming strength. In other words, when the muscle contracts, it overcomes the resistance and puts the object or your body into motion.
2. Eccentric Strength. In an eccentric contraction (often known as a yielding contraction), the muscle lengthens (stretches back to its original length) as it contracts. The more the muscle lengthens or the faster it is stretched the greater the tension that is developed. The eccentric contraction plays a very important role in controlling and stopping movement and in preparing the muscles for an explosive type contraction.
3. Isometric Strength. In an isometric contraction you exhibit strength, but there is no movement of the limbs. The muscle develops tension and there is some shortening of the muscle fibers and tendon, but there is no limb or body movement.