The importance of stretching and office ergonomics

Elly Parker@ellybabes

BarCamp Cork III – 14th Nov 2009

Background Data

External Studies: 6943 employee survey responses in Denmark

Hours per weekMouse use

Number(%)Number(%)Odds Ratio Odds Ratio

0 to <2.5 51 (5.9) 1.0

2.5 to <5 25 (5.7) 1.0

5 to <10 62 (7.9) 1.5

10 to <15 111 (10.0) 1.8

15 to <20 137 (13.2) 2.8

20 to <25 115 (14.2) 3.3

25 to <30 60 (17.2) 4.3

>= 30 42 (15.4) 3.8

Keyboard use

0 to <2.5 59 (12.6) 1.0

2.5 to <5 115 (11.1) 0.7

5 to <10 190 (9.9) 0.7

10 to <15 140 (10.4) 0.9

15 to <20 72 (11.4) 0.8

10.9% said they experienced tingling / numbness in the right hand at least once a week in the last 3 months

Statistically elevated risk of injury from increased mouse usage but not from keyboard until 20 hours reached

Note : results were self reported but show similar trend to site findings

Keyboard is safer than mouseHigher PC usage = higher risk

My Company Safety StatisticsMicro Activity Cause Count

Mouse Use – Technique 48

Posture 27

Mouse Use – Excessive 22

Laptop Use – Direct 11

Typing – Technique 8

Other 5

Mouse Use – Improper fit 4

Sitting 4

Document 2

Monitor Use 2

Phone Use 1

Typing – Excessive 1

Total 135

At least 55% of injuries were mouse related - 7 % keyboard related

85 of these reported injuries (63%) said they regularly spent more than 6 hours a day on their PCs

Keyboard is safer than mouseHigher PC usage = higher risk

What is Ergo?

• "the study of the relationship between the employee and their work environment to increase safety...comfort...and productivity."

What can happen with bad ergo?

• Repetitive Strain Injury• Back Pain• Neck/Shoulder Pain• Stress• Trapped Nerves

• Scott Adams – lethargic on left butt cheek, active on right!

Workstation Ergonomics: Neutral Posture

1. Back upright while maintaining curve of lower back

2. Top of monitor at eye level or slightly lower

3. No glare on screen 4. Sit at arms length with shoulders

comfortably down and back 5. Feet on floor or footrest; knees

slightly lower than hips 6. Use a document holder when

reading from printed original 7. Relaxed in a straight, neutral

position without resting on the edge of a surface.

8. Arms and elbows close to body 9. Center monitor and keyboard in

front of you 10. Fingers gently curved

downward 11. Use a stable work surface 12. Take frequent micro-breaks

Computer Workstation Tips• Order of adjustments is important

– Adjust chair first– Then adjust keyboard and mouse– Finally, adjust monitor

• No single “right” way to sit; everyone is a little different– Varying position throughout the day is helpful

• Stretching, especially at the beginning of the day, can prevent fatigue and soreness

• Take micro-breaks (1 minute or less every 30 minutes)

9

Chair Tips

• Tighten the backrest so that it does not give way with body weight

• Readjust the chair throughout the day to vary body position

10

Keyboard Tips• Keep wrists and hands in line with forearm in a

straight, neutral position.

• Avoid resting wrist on a surface edge or even a pad while keyboarding

VERY WRONG!

11

Mouse Tips• Mouse should be held loosely and fit naturally

under the palm of the hand.

• Avoid holding the index finger elevated between clicks

• Tips for keyboards also apply to mouse (Slide 4)

Monitor Tips

• Top of screen at or just below eye level (exception: bifocals and trifocal lens wearers).

• Monitor should be directly in front of user; screen distance about arms length away.

• Room lighting - avoid backlight, shadows or reflective glare.

Work Surface TipsWork Surface Tips

Work within Work within your normal your normal

range of range of motionmotion

• Usual zone – for most frequently used items e.g.

keyboard and mouse

• Occasional zone – for items used periodically e.g. phone, calculator

• Rare zone – for items that are seldom used or for display only

Note About Short Cuts• While using keyboard shortcuts are encouraged, it is important to note • that awkward hand postures may result when performing shortcuts • utilizing only one hand; engaging in repetitive awkward hand postures • may pose an ergonomic risk over time.• When performing frequent keyboard shortcuts, recommend utilizing • two hands in order to keep the hands/wrists straight.

Using the left hand to activate alt-tab, results in an awkward wrist posture for this user. This would be considered a risk if repetitively performed over time.

Utilizing two hands enables the user to maintain neutral wrist postures

Risks or precautions to remember when stretching

• Good posture is maintained throughout. There should be no stress on the joints only a stretch in the muscles.

• Repeated excessive stretching can cause micro-trauma to the tissues and nerves. Stretches should be comfortable throughout.

• Prolonged stretching can reduce the blood supply and oxygen to the tissues. Stretches should only be held for up to 30 seconds.

• A quick stretch causes the stretch reflex to kick in which inevitably tightens the muscle and can lead to injury. Stretches should be slow and sustained.

Personal Exercise ProgramTo stretch the musclesTo stretch the musclesat the back of the neckat the back of the neck

Bend your head forward until you feel a stretch behind your neck. Hold for approx. 5 secs.

Repeat 3 times.

To ensure full range To ensure full range movement of the neck.movement of the neck.

Bend your head backwards as far as is comfortable.

Hold for approx 5 seconds. Repeat 3 times

• Pull your chin in. • At the end of the poke position; take hold of your

chin with your hands. • Push your chin carefully further backwards. • Hold for a moment & feel the stretch in your neck.• Repeat 3 times.

To correct poking head posture and stretch the neck extensor muscles at the back of the neck.

To stretch the upper To stretch the upper trapezius muscle at the side trapezius muscle at the side of the neck and upper of the neck and upper shoulder regionshoulder region

Put one hand over your head onto the opposite ear.

Tilt your head and let the hand on your ear bend away from the side to be stretched.

Repeat 3 times to both sides

Personal Exercise Program

• Stand straight with one hand on your hip and the other straight up.

• Bend to the side with opposite arm reaching overhead. Keep your pelvis in mid position.

• Repeat 2 times to each side.

Reach up to the ceiling and hold for 5 secs, then drop into forward bend (touch the toes position). No bouncing!!

Link hands behind back, palms facing outward. Stretch up and away from body feeling the stretch across the front of the chest. Hold for 10 secs, repeat 2-3 times.

Link hands in front of body, palms facing outward. Stretch away from body, feeling the stretch through the shoulders and across the back. Hold for 10 secs, repeat 2-3 times.

These two stretches can be linked into one movement.

• Sit or stand. • Roll your shoulders in

both directions• Repeat 3 times

For shoulder relaxation.

To stretch the posterior shoulder muscles and triceps.

Stand or sit. Stretch one arm over the opposite

shoulder by pushing it at the elbow with your other arm.

Hold the stretching approx 15 seconds. Relax.

Repeat 3 times

Personal Exercise Program

• Stand holding onto a support. Bend one knee and take hold of the ankle.

• Do not lock the knee of the leg that you are standing on.

• Draw your heels towards your buttock. • Tilt your hips forward so that your knee

points toward the floor. • Feel the stretch in the front of your thigh. • Hold 15 seconds• Repeat 3 times

Quadriceps Muscle Stretch

Personal Exercise Program To stretch the forearm extensors

Let your hand drop down. Gently assist the movement with your other

hand. Hold for 15 seconds

Prayer position

Sit or stand. Forearms horizontally in front of

you and your palms together. Push palms together for 5 secs. Repeat 3 times. To increase stretch, bend hands

from side to side slowly, keeping palms pushed together.