How Does the Diaphragm Muscle Help You Breathe?

Take a deep breath in…and out… Notice how your chest moves in and out with each breath. You can thank your chest muscles, especially the diaphragm, for helping your lungs work. Now let’s learn some amazing facts about your diaphragm muscle!

Where is the diaphragm muscle in the body?

diaphragm muscle spasms during hiccups

The diaphragm is a thin and wide muscle that’s located right under your lungs. Take a look at this picture of the diaphragm. What do you notice about the shape? Some people think that the diaphragm looks like a dome, parachute, or an upside-down coffee filter!

The diaphragm acts like a wall between your chest and abdomen. Since it extends from your left to right side and also your front to back side, it separates your lungs from your stomach and intestines.

As a result, your lungs live “upstairs” in your chest, and your stomach and intestines live “downstairs” in your belly.

What controls the diaphragm muscle?

Most of the time, breathing happens automatically, even when you are sleeping and dreaming! Sometimes, you might choose to control your diaphragm, like when you hold your breath or pant like a puppy.

All of this happens because your brain sends signals through the spinal cord which then goes down nerves to the diaphragm muscle.

Realistic Human Brain Anatomy Picture

How does the diaphragm help you breathe?

The 2 phases of breathing are (1) inhaling, which means breathing in air, and (2) exhaling, which means breathing out air.

  1. INHALE: When you inhale, the diaphragm muscle contracts (squeezes) and moves down. This makes the space inside your chest bigger, so air gets pulled into your lungs.
  2. EXHALE: When you exhale, the diaphragm muscle relaxes and moves back up. This makes the space inside your chest smaller, so air gets pushed out of your lungs.

Take a look at this cool video to see how your diaphragm and lungs work together to help you breathe in and out!

  • HICCUPS – Hic! Hic! Every now and then, the diaphragm gets confused and moves at the wrong time. Oops! When you get hiccups, your diaphragm is squeezing in between your breaths, instead of squeezing when you breathe in.
  • HERNIAS – Sometimes the diaphragm has trouble doing its job as a wall between the chest and belly. For example, if the diaphragm doesn’t develop normally before a baby is born, the stomach and intestines can end up the chest. This makes the chest very crowded, and the lungs don’t have enough space to grow.

Science experiment for kids: Make a working diaphragm model!

Make a model lung activity from Human Body Learning Lab

Check out Human Body Learning Lab, pages 84 to 85, for cool way to make a lung model with recycled materials. The lung model activity shows how the diaphragm muscle works to help you breathe.

Human Body Learning Lab is filled with kid-friendly science facts, memorable experiments, diverse realistic images, and practical health tips.


Updated on April 5, 2023 by Betty Choi, MD

Updated on April 5, 2023

by Betty Choi, MD