1. Turning a doorknob
- Supinator: Action; Supinates forearm at radioulnar joints. Innervation: Deep radial nerve.
- Pronator teres: Action; Pronates forearm at radioulnar joints and weakly flexes forearm at elbow joint. Innervation: Median nerve.
- Pronator quadratus: Action; Pronates forearm at radioulnar joints. Innervation: Median nerve.
2. Throwing a baseball overhead-
- 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.
- 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.
- Supraspinatus: Action; Assists deltoid muscle in abducting arm at shoulder joint. Innervation: Suprascapular nerve.
3. Kicking a ball-
- Quadriceps femoris: Action; Rotates the hip laterally; also helps adduct the hip. Innervation: Femoral nerve
- Psoas major: Action; Psoas major and iliacus muscles acting together flex thigh at hip joint, rotate thigh laterally, and flex trunk on hip as in sitting up from supine position. Innervation: Lumbar spinal nerves L2-L3.
- Rectus femoris: Action; muscle acting alone also flexes thigh at hip joint. Innervation: Femoral nerve
4. 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.
- Sartorius: Action; Weakly flexes leg at knee joint; weakly flexes, abducts, and laterally rotates thigh at hip joint. Innervation: Femoral nerve
5. Walking-
- Quadriceps femoris: Action; Rotates the hip laterally; also helps adduct the hip. 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.
- Gastrocnemius: Action; Plantar flexes foot at ankle joint and flexes leg at knee joint. Innervation: Tibial nerve.
6. Breathing-
- Diaphragm: Action; Contraction causes it to flatten and increases vertical dimension of thoracic cavity, resulting in inhalation; relaxation 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).
- External intercostals: 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.
- Internal intercostals: Action; Contraction draws adjacent ribs together to further decrease anteroposterior and lateral dimensions of thoracic cavity during forced exhalation. Innervation: Thoracic spinal nerves T2–T12.
Source: Tortora, G. J., & Derrickson, B. (2011). Principles of anatomy & physiology. (13th ed., pp. 363-482). Danvers, MA, Wiley.