Module 2: Your Chair Is Your Throne – Make It Comfortable

• Slide all the way back against the backrest.
• The front edge of the seat should not press into the back of your knees.
• You need at least 2-3 inches (2-3 fingers) of space behind your knees to allow wiggle room for the legs.

Conversely:

• If your seat length is too short, leaving a gap of more than 3-4 inches (3-4 fingers) of space behind your knees, you will suffer from lack of thigh and back support.

Use your fingers to measure how much space is behind your knees if any:

• Check to ensure that your seat is wide enough for your hips.
• A seat at least 1-2” wider than the widest point of your hips is ideal but not always possible.
• Some seats are comfortable even if hips are slightly wider as long as there is no hard edge or upward curve.
• Standard sized ergonomic chair seats range from 18-21” wide.
• The wider the seat, the wider the armrests which is an issue for those with narrow shoulders, especially females.

Step 4: Lumbar (low back) Support Height Adjustment

Many chairs will allow you to adjust the lumbar support up and down to fit the curve of your back.

• Lumbar support in the first image is adjusted by raising and lowering the entire backrest.
• In the second image, adjustments are made by reaching behind the chair and sliding a small lumbar support up or down.

Adjusting your lumbar support height (if adjustable): 

• Slide back against the backrest.
• Raise or lower the lumbar support until the largest curve of the backrest fits the largest curve in your low back (as seen in the image)
• Notice how the largest curve of the low back is ABOVE the hip bones.
• You can reach back with your hand to feel the largest curve in your lower back. The lumbar support of the backrest should meet your hand.
• Note: Many workers have the lumbar support too low so that it hits the bony hips instead fitting the curve of the low back. This leaves the back unsupported and the chair fitting poorly.
• You might need to adjust the lumbar support up and down a few times until you find the right fit.

Remember to raise or lower the backrest ONLY to align the lumbar support with the curve in your low back. People mistakenly raise the backrest for more upper back support which throws off the lumbar support.

Some chairs allow you to adjust the AMOUNT of lumbar support, usually by turning a knob or inflating an air bladder inside the backrest. This feature is helpful for those requiring maximum support and those with a larger curve in the lumbar spine.

Adding a back cushion: Sounds easy right?

If you prefer extra support in the lower/lumbar area of your back, a back cushion is an economical solution. There are many choices as well as tips you need to be aware of:

• Beware: Back cushions can push you forward a couple of inches so that your chair does not fit properly. You may need to readjust your seat length to prevent a large gap behind your knees. (Aim for 2-3” of space.)
• Seat length does not adjust: If your chair does not have an adjustable seat, you may need a very thin back cushion or a chair replacement.
• No upper back support: Since back cushions push you forward a couple of inches, your mid to upper back may lose contact with the backrest leaving you unsupported. Consider adding a full-length back cushion to maintain mid to upper back support or use a very thin lumbar support.
• Smaller back cushion: A towel roll or small pillow may be used to provide lumbar support or to see if a back cushion would be helpful.

Smaller lumbar/back cushion

Adding extra seat cushion: Words of caution

Adding a seat cushion for greater comfort can be helpful, especially with so many inexpensive choices and materials. Some even have a cutout for sensitive tailbones. However, there are issues to consider:

• Caution: Adding a seat cushion may throw off the lumbar support height by raising you in the chair.
• Make sure to readjust the backrest height for proper lumbar support.
• If your chair does not have an adjustable backrest height or lumbar support, then a seat cushion cannot be added, and a chair replacement may be required.
• Seat cushions can be helpful for raising your seat height an extra 1-2” when needed to prevent uphill reaching to the desktop.  Again, the chair must have an adjustable backrest height or lumbar support.

Lower and narrower backrests (below the shoulder blades) are best for work tasks requiring more upper body and arm mobility.

Workers who sit for many hours and perform intensive, focused work tend to prefer taller backrests that support the shoulders. Taller backrests are also more comfortable when reclining.

Headrests are not always necessary or desired. You may be a candidate for a headrest if you:

• Like to occasionally recline in the chair
• Perform long hours of intensive, focused computer work
• Have a history of neck pain that improves with support

Headrests are designed to support the curve of the neck and base of the skull. Headrests that contact the back of the skull create uncomfortable pressure and a forward head posture. If you choose to use a headrest, make sure that it can be adjusted for proper fit:

• Some headrests can be raised or lowered
• Some headrests tilt up and down to better accommodate the curve of your neck
• Ideally, a headrest should offer both adjustments
• A few headrests are removable or flip backwards out of the way when not in use

Most ergonomic chairs should be equipped with levers that allow you to recline the backrest.

• Tilt Tension Knob: Most chairs have an adjustable tension knob to control backrest tilt. Lighter workers may need less tension while taller or heavier workers may need more tension.
• Back Lock Lever: Some chairs also have a lever that allows you to adjust and lock the backrest into your preferred reclining angle.

Note:  At the very least, a chair should have a tilt tension control.  Having both features is nice to help maximize comfort.

Some chairs provide the added option of tilting the entire chair and seat forward or backward with either a control lever or free-floating mechanism:

• Most people prefer a level seat for an upright typing posture.
• Some prefer periods of reclining for resting and comfort.
• Occasionally, a worker may prefer a slightly forward seat tilt for intense typing or focus.

Should you use arm rests?

Pros of using armrests

• Can provide neck and shoulder support
• Can reduce discomfort and fatigue in some workers
• Can be used for resting when the worker is not typing

Cons of using armrests

• Not all armrests adjust correctly for typing
• Many standard armrests are too wide for females
• Armrests can increase pressure to the elbows and soft tissue of the forearms
• Armrests can bump into the desk and make it harder to reach the keyboard
• Armrests can make it difficult to work at a corner desk by bumping into the desk and forcing more of a reach (more on corner desks in the next modules)
• Armrests can be more harmful than helpful when adjusted incorrectly

The verdict

• Armrests can provide valuable support to the neck, shoulders and spine but only if they fit properly and do not get in the way.
• Not everyone prefers to use armrests. Many workers are comfortable typing for hours without armrests, as long as they are in a proper posture.
• If armrests do not fit correctly, it is recommended that you type without them. You can still use them for rest when you are not typing (about 10-20% of the day is enough rest for most people’s shoulders).

If you use arm rests, let’s get them adjusted

1. Relax: With your hands in your lap, relax your neck and shoulders.
2. Arm Angles: Bend the elbows approximately 90 degrees so that your forearms are parallel to the floor as if you were typing.
3. Height: Raise armrests until they just meet your forearms without elevating shoulders.
4. Width: If arm pads slide or rotate, adjust them in or out until they line up under your shoulders. On some chairs, the armrests adjust in or out where they attach underneath the seat cushion. Due to narrower shoulders, some females will not be able to get the armrests close enough to the body unless they have a narrower chair or highly adjustable armrests.
5. Keep arms at sides: Elbows should relax near your sides without having to reach out sideways to use the armrests.
6. Length: If arm caps adjust forward and backward, fine tune the length to distribute pressure comfortably over the forearms and to prevent armrests from bumping into the desk.

Problems	Description	Solutions
Armrests are too high	Pushes shoulders upward, increases tension on the neck and shoulders and causes pressure at the elbows and forearms.	Lower arm rests until they just meet your forearms without pushing arms and shoulders upward. If armrests do not lower enough either move them out to the side and only use them for occasional resting, or remove them If armrests are not removable and are in the way, a chair replacement is required
Armrests are too wide	Causes the elbows to reach out to the side placing stress on the neck and shoulders and causes awkward wrist posture while typing	Slide or rotate arm pads inward until they line up under shoulders. If armrests do not slide or rotate closer, then type without support and only use arm pads for occasional resting
Armrests are too long	Causes armrests to bump into the desk. Makes it harder to reach the keyboard. Prevents you from being able to work in a corner desk.	If arm caps are adjustable, then slide backward out of the way. Drop armrests under the desk surface to prevent bumping, especially in corner desks (see other solutions later for corner desks). If armrests do not lower or slide backward far enough, then see if they are removable. If not removable, then a chair replacement is required.

Castors/Wheels:

Many chairs come standard with castors for carpet. Higher quality chairs allow you to select castors for either carpet or hard surfaces. Hard surfaces such as wood or tile require softer or locking castors to prevent chairs from rolling too easily. If you have carpet castors on a harder floor, you may place a large piece of thin carpeting under your desk and chair to prevent rolling.