The main purpose of the gastrocnemius muscle is to facilitate leg movements, such as jumping, walking, running and knee bending. The gastrocnemius muscle pushes the leg down during these types activities. The location of... More »

Actions of the gastrocnemius muscle include pulling the heel up and extending the foot downward. It also provides the force necessary for running and jumping. More »

www.reference.com Science Human Anatomy Muscles

The arrector pili muscle is made to lift the hairs on the body, which causes air to get trapped between the hairs and provide a layer of insulation against the cold. These muscles can also react in cases of fear and give... More »

Actions of the gastrocnemius muscle include pulling the heel up and extending the foot downward. It also provides the force necessary for running and jumping. More »

www.reference.com Science Human Anatomy Muscles

According to the BBC, antagonistic muscles are pairs of muscles that work by alternately contracting and relaxing. In the human leg, the quadriceps and hamstrings are one example of antagonistic muscles. As York College ... More »

The muscles that control the knees include the quadriceps, hamstrings and calf muscles. These muscles all work together to allow the knee to move freely in order to walk, run, kick and jump. More »

While both the pectoralis major and pectoralis minor muscles control the movements of the arm, the pectoralis major is specifically responsible for its lateral, vertical and rotational movement. In addition to this prima... More »