pennate muscle

physiology

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July 23, 2026

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A pennate muscle is a type of muscle where relatively short fibers attach diagonally onto a tendon that penetrates deep into the muscle. This arrangement allows pennate muscles to contain more and shorter fibers than parallel muscles of equal mass, enabling them to exert greater force. However, they cannot shorten as much as parallel muscles. This structure is common in the leg muscles of arthropods, where space is limited, and also found in muscles like the deltoid in the human shoulder. The term "pennate" can also refer to a type of bilaterally symmetrical diatom.12

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muscle
Muscles that work skeletons
…shoulder is said to be pennate; relatively short fibres attach diagonally onto a tendon that penetrates far into the muscle. The ankle muscles shown in Figure 4B are pennate muscles, but most of the hamstring muscles (at the back of the thigh) are parallel. The adductor muscles of the shells…
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…shoulder is said to be pennate; relatively short fibres attach diagonally onto a tendon that penetrates far into the muscle. The ankle muscles shown in Figure 4B are pennate muscles, but most of the hamstring muscles (at the back of the thigh) are parallel. The adductor muscles of the shells…
Read More