In which type of contraction does the muscle contract and shorten, resulting in movement at the joint?

In a concentric contraction, the muscle generates tension and shortens simultaneously, resulting in movement around a joint. This type of contraction is what typically occurs when lifting a weight; for example, during a bicep curl, as you raise the weight towards your shoulder, your biceps muscle contracts concentrically.

In contrast, eccentric contraction describes muscle activity where the muscle lengthens while still under tension, usually occurring when lowering a weight. Isometric contraction involves the muscle generating force without changing length, meaning there is no movement at the joint despite the muscle being active. Isokinetic contraction refers to movement at a constant speed, which typically requires specialized equipment to maintain that constant velocity throughout the range of motion. Understanding these terms is essential for effectively designing training programs and coaching clients on proper lifting techniques.