Muscle main actions

main actions

Orbicularis pculi

close the eyelids, squint

orbicularis oris

closes mouth

masseter

elevates (opens) mandible

platysma

depresses (closes) mandible

zygomaticus

elevates (lifts) corners of the mouth

frontalis

elevates (lifts) eyebrows

sternocleidomastoid

(forward) flexes and rotates head

splenius group

extends neck

diaphragm

increases thoracic volume

internal intercostals

depresses (relaxes) ribcage

external intercostals

elevates (lifts) ribcage

rectus abdominis

flexion of trunk

external and internal obliques

flexion and rotation of the trunk

transverse abdominis

compresses the abdomen

erector spinae

extends vertebral column

trapezius

elevation, depression, retraction and stabilization of scapula

deltoid

abduction of arm at shoulder

latissimus dorsi

extension and adduction of arm at shoulder

pectoralis major and minor

adduction, flexion, and medial rotation of arm at shoulder

subscapularis

medial rotation of arm at shoulder

supraspinatus

abduction of arm at shoulder

infraspinatus

lateral rotation of arm at shoulder

teres minor

lateral rotation of arm at shoulder

biceps brachii

flexion of elbow

triceps brachii

extension of elbow

flexor group

flexes wrist and digits

extensor group

extends wrist and digits

gluteal group

extension of hip

iliopsoas

flexion of hip

tensor fasciae latae

abduction of leg at hip

adductor group

adduction of leg at hip

sartorius

flexion, lateral rotation of hip

quadriceps femoris group

extension of knee

hamstrings group

flexion of knee

gastrocnemius

plantar flexion (points foot)

soleus

plantar flexion (points foot)

tibialis anterior

dorsiflexion (lifts foot)

tibialis posterior

inversion (rotates big toe to the ground)

fibularis brevis and longus

eversion (rotates big toe to the sky)

iliotibial tract

attaches tensor fascia latae and gluteus maximus to lateral knee

patellar ligament

attaches quadriceps femoris group to tibia

calcaneal tendon

attaches gastrocnemius and soleus to calcaneus