There’s a lot of ergonomic advice online about how to sit properly. Most of it promotes the 90-90-90 rule — 90-degree angles at the hips, knees and elbows. Such advice is enough to give ergonomics a bad rap because it’s not so comfortable for most people. My suggestion is to open up the joints a little more to reduce that constricted sensation and the pressure on joints, nerves and muscles. Ultimately, the idea is to be good to your body and also be comfortable.

When talking about sitting posture or habits, being “comfortable” in a position is often just code for being used to it. And we all know that just because we’re used to something, it’s not necessarily good for us. Right?

So how should you sit? There are three basic sitting positions that will work for most people. With each of them, it‘s crucial that your lower back and upper pelvis area are well supported.

Upright Sitting

• The hips are slightly higher than the knees.
• The feet are underneath the knees, supported on the floor or slightly forward on a footrest.
• The seat of the chair is mostly level but can have a slight forward tilt, which will reduce the posterior tilt of the pelvis.
• The lower back is well supported.
• This is your basic good ergonomically correct position and comfortable with most people.

Declined Sitting

• The hips are a few inches higher than the knees.
• The seat is tilted forward, reducing the posterior tilt of the pelvis which happens with sitting.
• The feet are underneath the knees and on the floor.
• The lower back is well supported.
• The head and spine are upright and nicely aligned.
• This position opens up the hip and knees joints and promotes a more active sitting engaging the core muscles better.
• This position is the anti-slouch position.

Reclined Sitting, also known as the “low rider”

• The hips are level with the knees or slightly lower
• The seat is level or tilted slightly backwards
• The backrest is angled back between 95⁰-110⁰
• The lower back must be well supported
• The feet must be supported by an angled footrest.

You can take that reclined sitting a step further — not quite the lazy boy position, but still a good one to relax in your office, take a call or read some documents. Just make sure to use a headrest if your backrest is tilted back more than 120⁰.  The headrest is a misnomer.  You actually need to have your neck supported to maintain your cervical spine and not push your head forward.

I must say that I hesitated to present this reclined sitting position as a recommended posture as most people I see do it wrong. It looks more like they’re spineless and have slid off their chair.

They end up with unsupported lower back and thighs, thoracic flexion — upper body and shoulders hunched forward – and a forward head posture. In other words, major slouching and an ergonomic disaster. Does that sound familiar?

But reclined sitting works for some people as long as they’re well supported – I cannot emphasize enough the importance of having your lower back supported. And all the other elements in the work environment need to be ergonomically optimal too, such as the position of the monitor, keyboard, etc.

No matter which position you choose, remember that your body is made for movement, so get off your chair frequently. You should also get acquainted with your chair and all those levers so that you can change your sitting position during the day. Over time, you’ll notice less tension in your neck, shoulders and back, and your body will thank you.

What is your favorite sitting position to work at your computer? Is it good for your body?