You know that feeling when you first stand up and stretch after you’ve been sitting for too long, and you hear a symphony of pops and cracks in your back, neck, and elsewhere? It feels good, doesn’t it?

But what’s behind all that popping? Should you be worried?

Generally, no. When you “crack” your back, nothing’s actually cracking, splintering, or breaking. There’s even a technical term for it: crepitus.

Spinal manipulation, or an “adjustment,” can be done by yourself or by a professional, such as a chiropractor or other joint and spine specialist.

Let’s look at why backs make that “cracking” noise, some downsides to adjusting your back, and how to do it for the benefits.

Before we dive into how back cracking works, let’s talk a little bit about the anatomy of your spine. The spine consists of several major components:

  • Spinal cord: The spinal cord is a long, thin bundle of nerves that connects your brain to the nerves throughout your body.
  • Meninges: These are membranes around the spinal cord and brain that absorb impact to the spine. They contain a fluid called cerebrospinal fluid (CSF), which serves many other functions.
  • Spinal column: Also called the vertebral column, the spinal column is made up of 33 vertically stacked pieces of bone called vertebrae, running from just below your skull to the tailbone (coccyx). Each vertebra can move independently of each other, allowing your back to be flexible. Each vertebra is divided from the next by soft spinal discs. These discs are filled with a jelly-like fluid called nucleus pulposus. This provides a cushion between the vertebrae so they don’t hit or scrape each other.

Now that you have a good working knowledge of the spine, let’s move on to what’s happening when you adjust your back.

Theory #1: Synovial fluid and pressure

The most popular theories propose that adjusting a joint releases gas — no, not that kind of gas.

Here’s one process that many experts think is occurring:

  1. Cracking your back stretches squishy capsules on the outer edges of the vertebrae around joints called facet joints.
  2. Stretching these capsules allows the synovial fluid inside them to have more space to move around, releasing pressure on your back joints and muscles and moving your facet joints.
  3. When the pressure is released, synovial fluid becomes gaseous and makes the cracking, popping, or snapping sound. This quick change of state is called boiling or cavitation.

Theory #2: Other gases and pressure

An alternative explanation also involves gas. Some experts believe that gases like nitrogen, carbon dioxide, and oxygen build up between your joints over time, especially if your joints aren’t properly aligned and swell from poor posture like being hunched over or sitting for long periods of time.

When you stretch the joints out or move around in certain ways, the gas is released.

Why does it feel good?

This release of pressure is supposedly what makes back adjustments feel so good to lots of people.

Back cracking also causes endorphins to be released around the area that was adjusted. Endorphins are chemicals produced by the pituitary gland that are meant to manage pain in your body, and they can make you feel super satisfied when you crack a joint.

But there may be another, less physiological and more psychological process at work here.

A 2011 study suggests that you might associate the sound of cracking your back with a positive feeling of relief, especially when a professional chiropractor does it. This is true even if nothing actually happened to the joint — a placebo effect at its finest.

Before we move on, just remember that any back adjustments you or a professional make shouldn’t cause you any major pain.

Adjustments may be uncomfortable, especially if you stretch yourself too far or if you’re not used to the feeling of a chiropractor manipulating your joints. But you shouldn’t feel intense, sharp, or unbearable pain.

Here are some possible risks of adjusting your back incorrectly:

  • Cracking your back too quickly or forcefully can pinch nerves in or near your spinal column. A pinched nerve can hurt. A lot. And some pinched nerves can stay pinched and limit your mobility until you have them examined and treated by a professional.
  • Cracking your back forcefully can also strain or tear muscles in and around your back, including your neck muscles near the top of the spine and your hip muscles near the bottom. Strained muscles can be difficult or painful to move, and severe muscle injuries may require surgery.
  • Cracking your back frequently over time can stretch back ligaments. This permanent stretching is called perpetual instability. This increases your risk of getting osteoarthritis as you get older.
  • Cracking your back too hard or too much can injure blood vessels. This can be dangerous because many important vessels run up and down your back, many of which connect to your brain. One possible complication of this is blood clotting, which can cause strokes, aneurysms, or other brain injuries.

The safest way to crack your back by yourself is by stretching your back muscles.

Many experts recommend yoga or pilates led by a trained professional for the best results, but you can also just do a few back exercises at home for a quick adjustment.

Some of these exercises can also help reduce chronic back pain or increase your range of motion if you do them consistently.

There are several ways to do this that you can make a part of your daily routine. Try one or more of these and see which ones work best for you.

Knee-to-chest

  1. Lie on your back and use your hands to pull your knee up toward your chest, one leg at a time. Relax your back and neck into the stretch as you pull with your arms.
  2. Repeat 2–3 times.
  3. Try this move twice a day.

Variations on hand placement include:

  • putting your hand on your knee, below the kneecap
  • holding on to the back of your thigh, behind your knee
  • hooking your leg over your forearm

Lower back rotation

  1. Lie on your back and raise your knees up so they’re bent.
  2. Keeping your shoulders still, move your hips to one side so that your knees are touching the ground.
  3. Hold this position for 10 seconds, or for 2 deep breaths in and out.
  4. Slowly return your knees to their previous position and repeat in the other direction.
  5. Do this 2–3 times, at least twice a day.

Bridge stretch

  1. Lie on your back.
  2. Bring your heels back toward your butt so that your knees are pointed up.
  3. Pressing your feet into the floor, lift your pelvis up so that your body forms a straight line from your shoulders to your knees.

Another version of this, as shown above, involves placing your feet higher up; instead pressing your feet into the floor you place them onto a wall and perform the same pelvic lift. This provides different leverage and stretching for your back. It can put more pressure on your upper back or shoulders.

Seated lower back rotation

  1. While you’re sitting down, bring your left leg over your right leg.
  2. Put your right elbow on your left knee, then rotate your upper body to the left.
  3. Hold this position for 10 seconds, or 3 breaths, then return to your normal position.
  4. Repeat this on the opposite side with your right leg over your left leg and turning to the right.

Unless you’re a professional chiropractor or licensed to adjust joints, don’t try to manipulate individual back joints or discs by yourself — this can cause injury or damage.

Adjusting your back is generally safe if you do it carefully and not too often. Most of all, it should not hurt.

And while there’s nothing wrong with regular stretches, compulsively cracking your back a few times a day or more, or doing it too suddenly or forcefully, can be harmful over time.

See a doctor, physical therapist, or a chiropractor if you experience persistent discomfort or pain when you adjust your back, after adjusting (and it doesn’t go away), or if you have long-term back pain in general. These could all be signs of a back condition that needs medical treatment.