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Throwing a baseball overhead
Muscle # 1: Latissimus dorsi
Action: Extends, adducts, and medially rotates arm at shoulder joint; draws arm inferiorly and posteriorly. RMA: Elevates vertebral column and torso.
Innervation: Thoracodorsal nerve
Muscle # 2: Deltoid
Action: Lateral fibers abduct arm at shoulder joint; anterior fibers flex and medially rotate arm at shoulder joint; posterior fibers extend and laterally rotate arm at shoulder joint.
Innervation: Axillary nerve
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Kicking a ball
Muscle # 1: Gastrocnemius
Action: it is the plantar flexion at the ankle joint and flexion of leg at knee joint.
Innervation: Tibial nerve
Muscle # 2: Soleus
Action: it is the plantar flexion at the ankle joint
Innervation: Tibial nerve
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Doing sit ups
Muscle # 1: Rectus Abdominis
Action: it primarily flexes the lumbar spine, thus bringing the ribcage closer to the pelvis. It also assists in stabilizing the pelvis and maintaining posture. It plays a key role in supporting the abdominal organs and protecting the spinal column.
Innervation: Thoracic spinal nerves (T7 - T12)
Muscle # 2: Transversus abdominis
Action: it compresses the abdomen.
Innervation: Thoracic spinal nerves (T8–T12), iliohypogastric nerve, & ilioinguinal nerve
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Breathing
Muscle # 1: Diaphragm
Action: its contraction makes itself flat and increases the vertical dimensions of the which, which causes inhalation. On the other hand, its relaxation allows itself to move superiorly, as well as decreases the vertical dimension of the thorax, which results in exhalation.
Innervation: Phrenic nerve, carrying axons from cervical spinal nerves (C3–C5)
Muscle # 2: External intercostals
Action: it elevates the ribs, which results in inhalation. While, it depresses the rib cage, which causes exhalation.
Innervation: Thoracic spinal nerves (T2–T12)
REFERENCES:
Mallat, J., Marieb, E.N. & Wilhelm, P.B. (2016). Human anatomy (8th ed.). Washington, USA: Pearson.
Tortora, G.J. & Derrickson, B. (2017). Chapter 11: The Muscular System. In Principles of anatomy and physiology (15th ed.).