Nine years at a computer with terrible posture had wrecked my back, my neck, and my shoulders. Sound familiar? Here is the thing about sitting for a long period of time. It’s hard on the body. Most office workers spend long hours working at a computer, leading to prolonged periods of sitting. Low back pain is frequently observed among office workers due to extended sitting durations.
And your office chair probably isn’t helping. That is why some ditch the office chair and swap in an exercise ball (also called a yoga ball or stability ball) to make sitting a little more active. The idea is that the ball will give you better sitting posture, more core muscle activation, and more freedom to move around.
I’ve actually tested this myself. For a few months back when I first started focusing on fixing my own posture, I rotated between a stability ball and a desk chair. Some of it helped me. Some of it did not, and I will be honest with you about both.
This post shows you how to use an exercise ball as a desk chair the right way. We will cover sizing, posture tips, and how long to sit.
How to Use an Exercise Ball as a Desk Chair
When you finally decide to try out using an exercise ball, there are a few things you’ll want to focus on. Start by choosing the right size ball for your height and inflate it firmly so your hips sit slightly above your knees. Sit tall with your feet flat on the floor. Then start with short sessions and alternate with your regular desk chair.
That’s the short version. Here’s each step in a little more detail:
Choose the Right Size Ball for Your Height
The right size ball is incredibly important here. If you pick one that’s too small, your knees jam up above your hips. Too big and you are perched up like a kid on a barstool. Here’s a simple chart to start with:
- Under 5’5″ → 55 cm ball
- 5’5″ to 5’11” → 65 cm ball
- 6’0″ and up → 75 cm ball
55cm is recommended for persons 5′ to 5’5″ tall, 65cm for persons 5’5″ to 6′, and 75cm for persons 6′ and over. This isn’t necessarily the same process you’d use for desk chairs, though. If you are on the border, or your desk is on the taller side, size up. The goal is all the same: your hips should sit a little higher than your knees.
Inflate the Ball Just Enough
A squishy ball is a saggy ball. And as you can probably already imagine, sitting on a squishy ball isn’t great for your posture… or comfort. You want it firm and inflated enough that you sit up on top of it instead of sinking into it.
A good rule of thumb: base how much you inflate it on the diameter size. So for example, a 65cm ball should be about 65cm across when fully inflated. A firm, properly sized ball keeps your hips slightly higher than your knees, which helps your pelvis tilt forward a little and keeps your spine in a more neutral spot. A deflated one keeps the back slumped, which is exactly what we’re trying to avoid.
Keep Your Feet Flat on the Floor, Hip-Width Apart
Place both feet flat on the floor, roughly hip-width apart. Since you’re sitting on a ball instead of a regular chair, you’ll need your feet to help you balance. You shouldn’t feel like you’re constantly trying to stop yourself from rolling around.
Take a quick look at where your feet and knees are, too. If you can barely touch the floor without standing on your toes, your ball is probably too big. And if your knees are sitting much higher than your hips, it is too small. Ideally, you should be able to rest both feet comfortably on the floor without having to think too much about staying balanced.
Poor foot position used to be one of the most painful computer posture mistakes I made. It led to ankle dysfunction and excessive muscle tension throughout my legs. This caused me to sprain my ankle playing basketball, which led to 3 ankle surgeries.
Sit Up Tall and Keep Your Spine Neutral
Next, stack yourself up. Keep your hips over sit bones, your shoulders over your hips, and your head over your shoulders. Think of growing an inch taller through the top of your head, then let your shoulders relax.
A neutral spine just means your back keeps its natural curves. You’re not slumping, but you’re also not forcing yourself into that stiff, military-style “sit up straight” position. I walk through this in more detail in my post on good computer desk posture.
Gently Engage Your Core Muscles
The idea is that the instability of an exercise ball requires the user to increase trunk muscle activation and thus increase core strength, improve posture and decrease discomfort.
Here is where I have to be honest, because the research does not fully back that idea up.
One study found that using a yoga ball as a chair didn’t increase core muscle activation or strength, and strengthening your core requires active muscle engagement with exercises that use more effort than sitting on a yoga ball. So engage gently, sit tall, but do not expect the ball alone to build your back or core muscles.
Adjust Your Monitor and Keyboard Height
A ball does not adjust up and down like an office chair does. With a ball, your desk and screen have to meet you where you are. Try to position your monitor so the top of the screen sits roughly at eye level. Your keyboard should also be at a height where your elbows can bend comfortably at around 90 degrees, with your forearms resting about parallel to the floor.
This is exactly why I think a height-adjustable desk is so helpful if you are going to use a balance ball as a chair. Balance balls cannot raise or lower, so the desk has to. And I never want my elbow height to drop below my desk level. For me, that pulls my biceps into overuse, which can lead to repetitive strain of the biceps tendon up near the shoulder. I would rather raise the desk than wreck my shoulder.
Start With Short Sessions and Build Up
Do not go all day on day one. I cannot stress this enough.Start with 20 to 30 minutes. See how your back and hips feel. Then build up slowly over the following weeks. There is a real reason to pace yourself.
Studies have found that sitting on a stability ball can increase muscle activity in your upper back, change the way your pelvis sits, and cause more discomfort than a regular chair. In other words, that’s why I recommend keeping your sessions short at first instead of waiting until your back hurts to call it quits.
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Alternate Between the Ball and Your Office Chair
Here is my biggest takeaway from using the ball at my desk. Think of it as one supportive option, not the only option. Spend an hour on the ball, then switch back to your desk chair. Then maybe stand for a bit.
When you rotate back to your chair, you want a good one waiting for you. I explain this in more detail in my post on the best ergonomic chair for lower back pain. Your chair is still doing most of the work correcting your posture across a full day.
Repetitive strain injuries (RSI) don’t just care about the position we work in. An important factor to avoid is working in the same exact position for long periods of time. Because even with perfect posture, overuse of postural muscles can be a very bad thing. That’s why I rotate between using a desk chair, stool, exercise ball, and standing. I switch between these working positions multiple times a day.
Move While You Sit
This, honestly, is my favorite part of sitting on a ball. It encourages you to move, even if it’s just small bounces, gentle pelvic tilts, slow hip circles, or little shifts here and there. And that’s something I wish I’d understood during those nine years of sitting for hours on end, barely moving. I’d stay in the same position for so long without even realizing it. The ball gives you that little nudge to keep moving, and to me, that’s a win in itself.
Consider a Ball Chair With a Base and Backrest for More Stability
A regular exercise ball rolls around. That’s kind of the whole point, but it can also be a problem. If you’re worried about the ball rolling out from under you, a ball chair might be a better option. It’s basically a stability ball that sits inside a frame, usually with a base, a small backrest, and sometimes even wheels.
If you want my picks, here are the ones I’d recommend looking at:
- The exercise ball for keeping it simple.
- The ball chair if you’d feel more comfortable with a stable base and a little back support.
With a ball chair, you still get some of that active sitting experience, but you don’t have to worry as much about the ball slipping out from under you.
Is Sitting on an Exercise Ball Good for You?
It depends on how you use it. Let me give you both sides.
The possible upsides. Sitting on the ball is a form of active sitting, which means your body has to do a little work to keep you balanced instead of fully relaxing into a chair. It encourages you to move around, even if it’s just small adjustments. It can also remind you to sit up taller instead of slouching. Some people genuinely enjoy that and find that it helps them feel more awake throughout the day.
The real drawbacks. There’s no backrest, which means your spine doesn’t have anywhere to rest when you start getting tired. And eventually, you will probably get tired. That’s when you might notice yourself slouching again, even though you switched to the ball to avoid doing exactly that. There’s also the risk of the ball rolling out from under you, which isn’t something you’d normally worry about with an office chair.
And the research leans cautious here. One study looked at what happened when people sat on a stability ball for an hour. Researchers didn’t find any meaningful differences in trunk muscle activation or lower back posture compared with sitting in a regular chair.
There’s also the issue of muscle fatigue. Even though your muscles are doing small amounts of work to keep you balanced, that effort can become tiring over time. And without a backrest or lumbar support, you don’t have the same option to lean back and give your muscles a break.
So where does that leave us? I wouldn’t call the ball a magical fix. Instead, think of it as another option you can work into your day alongside regular sitting, standing, and taking breaks. For more on rotating through different setups, read my post on types of sitting positions.
Who Should Avoid Using a Ball at Work?
Using a ball at work is not the best idea for everyone. You may want to skip the ball, or at least clear it with a professional first, if you experience any of these:
- People with balance issues or dizziness
- Certain back injuries or conditions that flare with unsupported sitting
- Pregnancy
- Anyone whose pain actually gets worse while sitting on the ball
If you have back pain, sciatica, or any kind of injury, talk to a doctor or physical therapist before you make the ball your desk chair. If nerve pain is your situation specifically, I wrote about what helped me in my post on how to sit with sciatica.
My content is not medical advice. It is based on my personal experience and opinions. Do your research. And be the best advocate possible for your own healthcare.
My Honest Take on Using a Ball at Your Desk
The exercise ball is a useful tool, not a cure. It will not build your core or straighten your spine on its own, and the science is pretty clear on that. But what it can do is get you moving and remind you to sit tall. Just remember to size it right, inflate it well, keep your feet flat on the floor, start short, and rotate it with a real chair. That is the right way to use a stability ball at your desk. Try it for a few weeks, pay attention to your own body, and keep what helps.
If you want a free head start, grab my free eBook “3 Ways to Improve Computer Posture Immediately!” and join the free Computer Posture Newsletter for more experience-based tips like these.
Thanks for your interest in computer posture.
Todd Bowen, Certified Posture Specialist (NPI-CPS)
My content is not medical advice. It is based on my personal experience and opinions.