1. throwing a baseball overhead
- infraspinatus
action: lateral rotation of the upper limb at the shoulder
innervation: suprascapular nerve
- pectoralis major
action: horizontal abduction and adduction
innervation: medial pectoral nerve and the lateral pectoral nerve
2. kicking a ball
- gluteus minimus
action: abducts the hip
innervation: superior gluteal nerve
- gluteus medius
action: medial rotation of the lower limb
innervation: superior gluteal nerve
3. doing sit-ups
- rectus abdominis
action: compresses the abdominal viscera
innervation: Thoracoabdominal nerves (T7-T11)
- transverse abdominis
action: supports adjacent abdominal structures
innervation: Anterior rami of seventh to twelfth thoracic nerves, iliohypogastric and ilioinguinal nerves
4. breathing
- sternocleidomastoid
action: lateral rotation of the upper limb at the shoulder
innervation: accessory nerve
1. throwing a baseball overhead
- infraspinatus
action: lateral rotation of the upper limb at the shoulder
innervation: suprascapular nerve
- pectoralis major
action: horizontal abduction and adduction
innervation: medial pectoral nerve and the lateral pectoral nerve
2. kicking a ball
- gluteus minimus
action: abducts the hip
innervation: superior gluteal nerve
- gluteus medius
action: medial rotation of the lower limb
innervation: superior gluteal nerve
3. doing sit-ups
- rectus abdominis
action: compresses the abdominal viscera
innervation: Thoracoabdominal nerves (T7-T11)
- transverse abdominis
action: supports adjacent abdominal structures
innervation: Anterior rami of seventh to twelfth thoracic nerves, iliohypogastric and ilioinguinal nerves
4. breathing
- Intercostal muscles (External Intercostals)
action: Elevation of ribs during inspiration
innervation: Intercostal nerves (T1-T11)
- Diaphragm
action: Primary muscle of respiration; expansion of thoracic cavity
innervation: Phrenic nerve (C3-C5)