What are the characteristics of pennate muscle?

The characteristic of the pennate muscle is the alignment of the muscular fascicles in relation to its tendon. The fibres are attached obliquely, which allows a higher force at the expense of a smaller range of motion.

How is pennate muscles arranged?

In a pennate muscle the tendon runs through the length of the muscle, with the fascicles attaching at an angle. Sphincter muscles are characterized by a circular arrangement of fascicles around an opening. With contraction, the opening becomes smaller.

Why can pennate muscles generate more force?

The fibers of these muscles are shorter and are situated at an angle to the long axis of the muscle. Thus, if two muscles were of equal cross-sectional area, a pennate muscle would be stronger than a parallel fibered one because of its larger physiological cross-sectional area.

Do parallel or pennate muscles shorten more?

Pennate. Unlike in parallel muscles, fibers in pennate muscles are at an angle to the force-generating axis (pennation angle) and usually insert into a central tendon. Because of this structure, fewer sarcomeres can be found in series, resulting in a shorter fiber length.

What is pennate muscle?

A pennate muscle (also called a penniform muscle) is a muscle with fascicles that attach obliquely (in a slanting position) to its tendon. These types of muscles generally allow better stabilization and force production but less flexibility.

What is a pennate?

Medical Definition of pennate : having a structure like that of a feather especially : being a muscle in which fibers extend obliquely from either side of a central tendon.

What is the advantage of Pennate muscles?

The advantage of this arrangement, first appreciated by anatomists >300 years ago (5), is that more fibers can be packed into a given volume of muscle, and thus the force of a pennate muscle is greater than a parallel-fibered muscle of equal volume (6).

Why are Pennate muscles stronger than fusiform?

Other factors being equal, muscles with greater pennation, yet slower in contractile velocity, generate greater force and power than fusiform muscles because more sarcomeres contribute to muscle action.

How are pennate muscles oriented during a contraction?

In pennate muscles, fibers are oriented at an angle to the muscle’s line of action and rotate as they shorten, becoming more oblique such that the fraction of force directed along the muscle’s line of action decreases throughout a contraction.

How did the pennate muscle get its name?

The arrangement of fibers and tendons in these muscles resembles the veins and rachis of a bird feather, leading to the designation of such muscles as pennate (from Latin “penna” or feather; Fig. 1 A ).

Where are the organs located in the pennate muscle?

In pennate muscles, the organs are commonly found near the point of nerve entry in a central zone of the muscle.59,65 Occasionally, tendon organs may be found entirely within the tendon, 4 but the responsiveness of such receptors is as yet unknown.

What does oblique orientation of pennate muscle mean?

First, the oblique orientation of pennate muscle fibers means that only the component of fiber force oriented along the muscle’s line of action can contribute to whole-muscle force ( 4 ).