Pennate Muscles
In a pennate muscle, the fascicles form a common angle with the tendon. Because the muscle cells pull at an angle, contracting pennate muscles do not move their tendons as far as parallel muscles do. But a pennate muscle contains more muscle fibers--and, as a result, produces more tension--than does a parallel muscle of the same size. (Tension production is proportional to the number of contracting sarcomeres; the more muscle fibers, the more myofibrils and sarcomeres.)
This type of muscle arrangement is called pennate. Pennate muscles maximize the number of muscle fibers in a given space, allowing for greater force production. Examples of pennate muscles include the deltoid and gastrocnemius.
Strap
parallel
The muscle named for the arrangement of its fascicles is the "pennate" muscle. In pennate muscles, the fascicles are arranged obliquely to the tendon, resembling a feather's structure. This arrangement allows for greater force production due to the increased number of muscle fibers that can fit into a given area, making pennate muscles efficient for generating power. Examples include the deltoid and the rectus femoris.
parallel
The fascicles are short and attach obliquely to a central tendon that runs the length of a muscle.
Unipennate is not a muscle but a pennate is a muscle. This muscle is located throughout the human body that allows high force production but little motion.
Some examples of pennate muscles in the human body include the deltoid muscle in the shoulder, the rectus femoris muscle in the thigh, and the flexor carpi ulnaris muscle in the forearm. These muscles have fibers that run obliquely to the tendon, which allows for greater force generation.
The Pennate arrangement. The fascicles attach obliquely to the tendon.
short fibers, arranged obliquely to their tendons
pennate is the opposite of parallel (fusiform) parallel muscle eg biceps brachii has fibres which run parallel, whereas pennate fibres run diagonally to the axis of movement, unipennate, bipennate and multipennate refers to the number of tendonous attachments unipennate muscle fibers which converge on one side of a tendon ca be found in the gluteus maximus, bipennate fibers converge in a featherlike way towards a central tendon, and multipennate converge on more tendons such as deltoid which has three heads.
The adductor magnus is a pennate muscle. Its fibers run at an angle to the tendon, which allows for greater force generation and stability. This structure is typical of muscles that perform powerful movements, such as those involved in hip adduction.