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Throwing a baseball overhead
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
Subscapularis
Action: Medially rotates arm at shoulder joint
Innervation: Upper and lower subscapular nerve
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Kicking a ball
Rectus femoris
Action: All four heads extend leg at knee joint; rectus femoris muscle acting alone also flexes thigh at hip joint
Innervation: Femoral nerve
Gluteus maximus
Action: Extends thigh at hip joint and laterally rotates thigh; helps lock knee in extension. RMA: Extends torso
Innervation: Inferior gluteal nerve
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Doing sit-ups
Rectus abdominis
Action: Flexes vertebral column, especially lumbar portion, and compresses abdomen to aid in defecation, urination, forced exhalation, and childbirth. RMA: Flexes pelvis on the vertebral column
Innervation: Thoracic spinal nerves T7–T12
Transversus abdominis
Action: Compresses abdomen
Innervation: Thoracic spinal nerves T8–T12, iliohypogastric nerve, and ilioinguinal nerve
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Breathing
External intercostal muscles
Action: Contraction elevates ribs and increases anteroposterior and lateral dimensions of thoracic cavity, resulting in inhalation; relaxation depresses ribs and decreases anteroposterior and lateral dimensions of thoracic cavity, resulting in exhalation
Innervation: Thoracic spinal nerves T2–T12
Diaphragm
Action: Contraction of diaphragm causes it to flatten and increases vertical dimension of thoracic cavity, resulting in inhalation; relaxation of diaphragm causes it to move superiorly and decreases vertical dimension of thoracic cavity, resulting in exhalation
Innervation: Phrenic nerve, which contains axons from cervical spinal nerves (C3–C5)
Reference:
Tortora, G. J., & Derrickson, B. (2017). Principles of anatomy and physiology (15th ed.). Wiley Custom Learning Solutions. https://handoutset.com/wp-content/uploads/2022/05/Principles-of-anatomy-and-physiology-Wiley-2017-Derrickson-Bryan-H._-Tortora-Gerard-J..pdf