GROSS MUSCLE STRUCTURE
Traditional kinesiology texts frequently distinguish between PENNATE muscles and PARALLEL or FUSIFORM muscles.
- The structure of pennate or bipennate muscles permits them to concentrate large numbers of fibers on a tendon, which in turn relays the muscle's force to the bone. An example is the gastrocnemius.
- Fusiform muscles, because their fibers run more parallel to the tendon to which they attach, concentrate fewer fibers on that tendon, and consequently develop less force. An example is the sartorius or the biceps brachii.
You will do a self study on COMPOSITION OF FORCES that will help you see how muscle structure affects the magnitude of force a muscle can develop.
- Some large muscles, like the gluteus maximus, are organized so that they have large areas of attachment.
- Several muscles might act on a common attachment, as the gluteus medius and gluteus minimis do at the greater trochanter of the femur.