1. Throwing a Baseball Overhead
- Deltoid
- Action: shoulder abduction, flexion and medial rotation
- Innervation: Axillary Nerve (C5-C6)
- Triceps Brachii (long head)
- Action: extension of the elbow and shoulder
- Innervation: Radial Nerve
2. Kicking a Ball
- Quadriceps Femoris
- Action: knee extension and hip flexion
- Innervation: Femoral Nerve
- Gluteus Maximus
- Action: hip extension and external rotation
- Innervation: inferior gluteal nerve
3. Doing Sit-Ups
- Rectus Abdominis
- Action: flexes the vertebral column and compresses the abdominal contents
- Innervation: lower six thoracic nerves
- Iliopsoas
- Action: flexes the hip joint, assists in trunk flexion
- Innervation: femoral nerve (iliacus) and ventral rami (psoas major)
4. Breathing
- Diaphragm
- Action: primary muscle of respiration; contracts and flattens to expand the thoracic cavity during inspiration
- Innervation: Phrenic Nerve
- External Intercostals
- Action: elevate the ribs during inspiration
- Innervation: intercostal nerves