Muscles are tissues that contract to help parts of the body move. Learn more about how muscles work, what they look like, and how they're treated.
Doctor testing knee reflex with hammer
Hyporeflexia
Nurse visiting old man at home
What Is Progressive Muscular Atrophy?
Baseball player
What Are Yips?
Woman with stiff muscle in calf
Muscle Stiffness
Young person scratching their forearm.
Why Do My Muscles Itch?
A woman doing tricep dips
The Anatomy of the Triceps
An older infant or young toddler playing with a toy requiring fine-motor skills: using their fingers to move a big yellow bead along a stationary red wire support
Fine-Motor Skills: Everything You Need to Know
Person with noise sensitivity troubled by hyper-acute hearing in bed at night
The Anatomy of the Stapedius Muscle
Man holding chest, cardiac muscle tissue of heart
Everything to Know About Cardiac Muscle Tissue
Reflexes being checked for clonus
What Is Clonus?
x-ray of the esophagus
The Anatomy of Esophageal Diverticulum
A woman stretching their muscles in the gym
What Are Voluntary Muscles (Skeletal Muscles)?
Midsection of a woman with her hands on her aching stomach
The Anatomy of the Lower Esophageal Sphincter
Back muscles
The Anatomy of the Muscles of the Back
anatomy of heart
The Heart: Anatomy, Function, and Conditions
Medical: pains and sprains - stock photo
The Anatomy of the Peroneus Brevis
Woman with jaw pain
Anatomy of the Masseter Muscle
Anatomy of the brachialis muscle.
The Anatomy of the Brachialis Muscle
The pectineus muscle may be strained in a groin pull injury
Pectineus Pain: Causes and Treatment
Iliacus muscle
The Anatomy of the Iliacus Muscle
What Is Hypertrophy?
Photo of a woman stretching her groin.
The Anatomy of the Gracilis Muscle
Woman tapping on smart watch at home
The Anatomy of the Brachioradialis Muscle
Gym workout.
The Anatomy of the Pectoralis Minor Muscle
Anatomical photo of the lower leg.
The Anatomy of the Peroneus Longus Muscle
Man placing kinesiology tape on shins
Anterior Tibialis Muscle of the Lower Leg
Woman stretching her hip flexor
The Anatomy of the Iliopsoas Muscle
External intercostal muscles
The Anatomy of the External Intercostals
Photo of a man performing a bench press.
The Anatomy of the Pectoralis Major Muscle
Photo of runner's quads.
The Anatomy of the Vastus Medialis
Woman's gluteus muscle and body structure.
The Anatomy of the Gluteus Minimus
Unrecognizable athletic woman exercising on stationary bike in a gym.
The Anatomy of the Gluteus Maximus
Sporty couple stretching quads before a run
Anatomy and Function of the Vastus Lateralis
Woman in a yoga pose, stretching the deltoid muscle
Deltoid Muscle Anatomy and Function
front view of the arm of a young athlete woman with a dumbbell
The Anatomy of the Biceps
Woman suffering from shoulder pain, France
The Anatomy of the Serratus Anterior Muscle
Closeup of the back of a man's calf as he jogs up stairs
The Anatomy of the Soleus Muscle
Photo of a man performing calf raises in a gym.
The Anatomy of the Gastrocnemius Muscle
muscular legs of runner man running on trial mountain sea bay
Sartorius Muscle Pain: Everything You Need to Know
Man holding his painful elbow
The Anatomy of the Tendon Sheath
Photo of a man examination a patient's knee.
Anatomy of Synovium
Lift for the love of good health
The Anatomy of the Latissimus Dorsi Muscle
My neck has been in pain the whole week
The Anatomy of the Sternocleidomastoid Muscle
Gluteus Medius muscle
The Anatomy of the Gluteus Medius Muscle
Woman Doing Leg Extensions
The Anatomy of the Quadriceps Muscles
Rear View Of Female Athlete Against Black Background
What Are the Paraspinal Muscles?
A woman performing pelvic thrusts
Pelvic Floor Muscles: Anatomy, Function, and Treatment
Doctors looking at brain scans
What Is Hemifacial Spasm?
Model of the human body showing trapezius muscle
Trapezius Muscle Anatomy and Function
Old couple running together
What Is Exercise Intolerance?
Woman Putting Hair In Poney Tail
The Anatomy of the Rotator Cuff

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