Human Muscular System Trivia

Every move you make, from blinking to sprinting, runs on muscle. The human body packs in hundreds of them, working in coordinated pairs and covering three completely different types of tissue. This quiz takes you from the largest muscle in your body down to one so small it lives inside your ear.

Whether you've studied anatomy or just spent time in a gym, there's a good chance a few of these will surprise you.

Three Types, One Job

Muscle tissue comes in three flavors. Skeletal muscle is the kind you control on purpose, attached to bone by tendons and responsible for every deliberate movement you make. Smooth muscle lines your organs and blood vessels, working automatically without any conscious input. Cardiac muscle exists in exactly one place — the heart — and it never stops, contracting rhythmically for an entire lifetime.

Muscles Working in Pairs

Muscles rarely act alone. They're usually arranged in opposing pairs, where one contracts to create movement while its partner relaxes to allow it, then reverses the motion when needed. The biceps and triceps are the textbook example, bending and straightening the elbow in tandem.

Extremes, Big and Small

• The gluteus maximus, in the buttocks, is the largest muscle in the human body.
• The stapedius, tucked inside the middle ear, is the smallest, helping to dampen overly loud sounds.
• The masseter, used for chewing, is often cited as the strongest muscle relative to its size, thanks to the sheer force it can generate in the jaw.