PHYSICAL WELLNESS

the silent workers

SMOOTH MUSCLES

Smooth muscles are muscles you don’t control consciously. Instead, they work automatically to keep your body running smoothly. These muscles line the walls of hollow organs like the stomach, intestines, bladder, and blood vessels. Unlike skeletal muscles, they aren’t striped (striated) and they move slowly and steadily to keep vital processes going.

  • Move food through the digestive system (peristalsis)

  • Control blood vessel size to regulate blood pressure

  • Help the bladder store and release urine

  • Support breathing by controlling airways

  • Adjust pupil size in the eyes

SMOOTH MUSCLE BASICS

Common Terms + Simple Definitions

Here’s a mini glossary for smooth muscle related words you’ll see throughout the site:

Voluntary Muscle - Muscle you control on purpose (like lifting your arm)

Striated Muscle - Muscles with a striped appearance under a microscope (skeletal muscles look this way)

Muscle Fiber - The individual cell of a skeletal muscle

Motor Unit - A nerve and the muscle fibers it controls

Flexor - A muscle that bends a joint (like the biceps)

Extensor - A muscle that straightens a joint (like the triceps)

WHAT SMOOTH MUSCLES WORK WITH

SMOOTH MUSCLES + OTHER SYSTEMS

  1. Digestive System → Move food along and help absorb nutrients

  2. Urinary System → Control bladder contraction and ureter movement

  3. Circulatory System → Expand or contract blood vessels to direct blood flow

  4. Respiratory System → Relax or tighten airways in the lungs

  5. Nervous System → Autonomic nerves (sympathetic & parasympathetic) control smooth muscle activity

  6. Endocrine System → Hormones like adrenaline influence smooth muscle behavior (e.g., during stress)

HealthY Smooth MUSCLES…

Smooth muscles keep your body functioning behind the scenes. Without them, you wouldn’t be able to digest food, move blood efficiently, or breathe properly. They’re the quiet but constant workers that keep life going without you even having to think about it.