Sit Well, Feel Better - The Essential Guide to Adjusting Your Ergonomic Chair for Lower Back Support


A man having back pain and looking for ergonomic chair with adjustable mechanisms for lower back support

The humble office chair has an important role we shouldn't underestimate in supporting workers’ backs through thousands of hours of deskwork. An ergonomic chair has the advantage of adjustable mechanisms that provide support in the place that's most needed - the lower back. 

Understanding Ergonomic Chairs

An ergonomic chair provides support for the spine’s natural S shape. This helps maintain good posture by preventing slumping and reduces stress on the spine and pelvis when a worker is seated for long periods. Adequate support from an ergonomic chair leads to a more comfortable workday and enhanced productivity. On the contrary, poor support causes poor posture and stress on the spine, which can lead to lower back pain and injury.  

Approximately 4 million (16%) of the Australian population had back problems in 2017-18 and was the third leading cause of disease burden. Having a bad back means people are likely to suffer from body pain, poor quality of life, disability, and psychological distress. Moreover, back problems cost around $3.4 billion to the Australian health system during that period.

The Anatomy of an Office Chair

An ergonomic chair has multiple parts that can be adjusted to suit the user's needs. For example, the chair should accommodate a worker’s long legs with an adjustable seat pan and seat height, and the user's back can be supported with a height-adjustable seat back. Every adjustment made to a chair impacts the user’s posture and comfort level.   

Seat Height - Adjustable so the feet sit comfortably on the floor or footrest with knees at the right angle.

Seat Depth - The space between the end of the seat and the back of the knees should equal roughly two to three fingers. This ensures minimum stress on the backs of the knees and encourages blood supply to the lower legs.

Backrest - The important task of supporting the lower back and reducing the risk of overload and stress. The backrest encourages an upright sitting position and good posture.

Armrests - Provide support for the neck and shoulder muscles with the upper and lower arms at a 90-degree angle with relaxed shoulders. Workers can decide to remove the armrests if they prefer to work without them. 

Headrests - Support for the head and neck when the worker leans back. These are most often found on chairs used around the clock to provide support during continuous and repetitive muscle activity. 

Mechanisms and Movements

The mechanisms and movements in an ergonomic chair are the most important components. They allow the user the flexibility to change the chair to suit their body shape, accommodate the tasks they complete, and to help them gain the best possible posture. 

Tilt - The front of the seat can be tilted up and down. The forward-sloping seat allows good blood flow to the lower part of the body and reduces lower back pressure while seated.  

Multi-tilt - A 3-lever mechanism allows for an adjustable seat height, seat tilt, and back tilt. Each one can be adjusted independently of the other mechanisms. 

Knee Tilt - The angle of the seat pan can be adjusted up or down to alter the height of the knees.  

Synchronous Tilt - The backrest and seat pan recline on a different ratio when the user leans back. The most common ratio is 2:1, so if the back goes back 20 degrees, the seat pan goes up 10 degrees. This allows the worker’s feet to remain on the ground while maintaining a forward-looking gaze rather than up at the ceiling. By leaning back, the worker can stretch their chest without putting too much pressure on their thighs. Workers can tilt back in their chair while staying balanced for a comfortable shift from the upright posture.  

Lever Mechanism - The seat pan and back support adjustments are independent of each other. This way, users can move the back support without varying the angle of the seat pan. The only disadvantage of this chair is that a worker can adjust the chair so the ratio of the back and seat aren’t in sync. If the back is adjusted more than several degrees, best practices encourage a trained person to check the adjustment. 

Chair Mechanism and Your Health

Choosing a chair with the right mechanisms can grant long-term health benefits. A chair with multiple mechanisms means it can be adjusted to provide the best possible support in the most needed areas. Considering the number of hours spent seated at work, investing in a good quality chair equals investing in posture and taking steps to reduce the risk of musculoskeletal injuries. A little extra money spent on a good-quality chair can pay dividends for the rest of your life if it means staying injury-free.

Adjusting for Lower Back Support

When a chair doesn’t have adequate lumbar support, the lumbar muscles need to work harder to support the rest of the spine while seated. And back injury or pain is more likely when the lumbar works too hard over a long period. Poor lumbar support is the main reason for workers’ compensation claims caused by back injuries. 

To avoid injuring your back and make your seated day as comfortable as possible, follow these instructions to adjust your chair for optimal lower back support:

  1. Sit in the chair and check if your lower back is resting against the seat back. Adjust the chair until your back feels comfortably supported, with the most protruding part of the cushioning fitting into the lower back, just above waist level. 
  2. Check that the chair's back height is right for you, meaning the chair supports most of your back. 
  3. Make sure the armrest height doesn’t make it difficult to sit as close to the desk as you like, otherwise, you may lean forward in an unnatural position.
  4. Once you're happy with your chair setup, make sure you can maintain a good posture throughout the day. Remind yourself to stop whatever you're doing, take note of your posture, and adjust to avoid slouching or sitting in an unnatural or uncomfortable position.  

Read our article on lumbar support from your office chair for more information.

Making the Right Choice

An ergonomic office chair is an investment in your future back health. A good quality chair can make you feel comfortable throughout a long day and provide the support your lower back needs. Here are a few questions to consider when choosing the right ergonomic chair. 

  • What type of mechanism does the chair use?
  • Can the backrest height and angle, seat pan angle, and chair height be adjusted? 
  • What style of chair do you prefer - fabric or mesh back?
  • Do you like armrests or not?
  • Do you need a headrest?
  • Do you perform tasks that may require a specialist chair? 
  • Does your body shape require a petite or heavy-duty chair?
  • Are the chair’s wheels and base of good quality to take the weight for many years?  

Once you have decided on the chair’s features, there are a few ergonomic certifications and standards to look out for when shopping, including:

  • AFRDI (Australasian Furnishing Research & Development)
  • GECA Certification (Good Environmental Choice Australia)
  • Manufactured in Australia

Maintenance and Care

The office chair is a hard-working piece of equipment, yet few chairs receive the attention they deserve. Maintenance can keep an office chair providing adequate support for a decade or more, and this can include:

  • Check the chair for any loose screws, bolts or parts, and tighten as required, every six months. 
  • Lubricate the mechanisms following the manufacturer’s instructions to ensure they keep moving freely. 
  • Turn the chair on its side so you can inspect the casters for any debris caught, which may stop the chair from moving freely. 
  • Vacuum the chair seat to remove any build-up of dust and debris. 
  • Use a damp cloth to wipe over the casters and base. 
  • Keep the chair out of direct sunlight to keep the fabric and plastic in good condition. 

Beyond the Chair: Ergonomic Practices in the Workplace

While the chair is the most important aspect of back support, it’s only a piece of the puzzle. One of the best things you can do for your back's health is to stand up. Changing from the sitting position to standing takes pressure off the lower back. A standing desk allows you to alter your position throughout the day so your back isn’t in the same position for prolonged periods. Step away from your desk regularly and walk around the office to keep your legs and lower back moving. In between walks, do some stretches at your desk in the standing and seated positions, as tight lower back muscles are the main cause of pain. Read our article on 7 lower back stretches to do at work. 

While seated, your feet should be comfortably flat on the floor. If not, use a footrest. Your hips and knees should be at a 90-degree angle. Make sure the monitor is at arm’s length away and you aren’t struggling to see the screen. It’s natural to lean forward if the monitor is too far away, which limits proper lower back support by the chair's back. 

Take the time to look at your office chair and its mechanisms. If it can’t be fully adjusted consider upgrading to a chair that will provide better support for your back. 

Check out our wide range of ergonomic office chairs here. If you have any queries about which chair is best for you, contact Ergolink at (08) 9240 7066, visit our website or showroom, or contact us online.