Muscle Lab

Welcome to Dr. Kate Brilakis' Learning Portal

muscles of anterior torso

muscles on the anterior surface of the body are usually involved in FLEXION

muscles on the posterior surface of the body are usually involved in EXTENSION

muscles on the medial surface of the body are usually involved in ADDUCTION

muscles on the lateral surface of the body are usually involved in ABDUCTION

rhomboideous minor
rhomboideous major
erector spinae

tibialis anterior
soleus
gastrocnemius
fibularis longus

intercostals
transverse abdominus
deltoid

muscles of posterior torso

muscle to bone...
origin:
the origin of a muscle is the point where it attaches to a bone that remains stable/immobile during the muscle's action. usually a proximal attachment.

insertion:
the insertion is the point where the muscle attaches to a bone that moves during the muscle's action. usually the distal attachment.

movement:
when a muscle contracts, the insertion pulls the bone it's attached to, bringing it closer to the origin.

pectoralis major
pectoralis minor
serratus anterior
rectus abdominus
external oblique
internal oblique

example:
biceps brachii:
the origin is on the scapula
the insertion
is on the radius
when the biceps contracts, it pulls the radius closer to the scapula, causing flexion of the elbow

muscles of the arm