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DRIVING AND BACK CARE
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Every day, almost 90% of journeys
and 92% of miles traveled are made in cars or ground transportation
(buses, trucks). For almost 180 millions of us, driving
is the primary means of transportation, for journeys to
and from work, to the store, and for pleasure. On average,
men drive 44 miles and women drive 34 miles each day. We
Americans love our cars. For some Americans, driving a motorized
road vehicle is also their job: truck drivers, bus drivers,
ambulance and fire trucks, police, taxis etc.
Modern car and truck designs
have come a long way in their design over the past 20 years,
with better styling, better features, better fuel efficiency
and better comfort. But is there any evidence that driving
and the design of modern car, bus or truck seats might play
a role in causing some of the back injuries that plague
Americans each year?
Why is driving different
to ordinary sitting?
If your car isn't moving,
then sitting in a driving seat probably isn't much different
to sitting in a padded chair, but as soon as the vehicle
starts moving things change. Unlike regular sitting, while
a vehicle is in motion the body is subject to different
forces: to accelerations and decelerations, to lateral swaying
from side to side, and to whole-body up and down vibrations.
Also, when driving the feet are actively being used, the
right foot on the gas (accelerator) pedal, the left on the
brake, and in a stick-shift also on the clutch. When the
feet are active they cannot be used to support and stabilize
the lower body as normally happens when they are placed
on the floor during normal sitting in a chair. There is
evidence that the combination of these factors, coupled
with the design of the car seat itself, can increase the
chance of back problems for some people.
Is driving associated with
back problems?
Laboratory research has studied
the effects of whole-body vibration when a person is sitting
in a car seat. The lumbar spine has a natural resonant frequency
of 4-5 Hz , and results show that this natural frequency
can be excited by laboratory simulated vehicle driving,
and this can lead to high spinal loadings in the lower back,
and this in turn could result in greater postural discomfort
and an increased risk of low back pain and injury.
A number of research studies
have investigated possible associations between driving
and back problems, and generally these studies have found
significant results.
A recent comparison of drivers
in the USA and in Sweden found that in each country 50%
of those questioned reported low back pain. Analysis of
the possible reasons for this revealed that long-term vibration
exposure from driving was among the highest risk factors
for neck, back and low back problems. Another recent Swedish
study of over 1,000 salespeople found significantly increased
risks of neck and low back pain among those who drove long
distances and spent a long time each day in their car.
Gender appears to play a significant
role in the likelihood of developing driving-related back
problems. A survey of over 7000 Parisians found that even
though the incidence and severity of low back pain was higher
in women, driving was only associated with back problems
in men. The importance of driving as a risk factor increased
with driving time, and was especially significant for men
who drove 4 hours or more each day.
A survey of over 1400 urban
transit drivers showed that difficulties with the ability
to correctly adjust the driving seat have significant effects
on the prevalence of low back problems.
However, it seems that driving
need not always increase the risk of back problems. A survey
of over 100 members of the Royal Canadian Mounted Police
found no statistically significant associations between
driving a patrol car and the likelihood of experiencing
back pain, which was comparable for drivers and other police
officers.
Is there an ideal car seat
design?
Based on a detailed analysis
of information from peer-reviewed scientific journals and
texts, automotive engineering reports, and the National
Library of Medicine a series of requirements for the optimal
car seat design have been developed. Ideally, the optimal
car seat should have:
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1. adjustable
seat back incline (100 degrees from horizontal is optimal)
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2. changeable
seat bottom depth (from seat back to front edge) |
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3. adjustable
seat height |
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4. adjustable
seat bottom incline |
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5. seat bottom
cushion with firm (dense) foam |
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6. adjustable
lumbar support (horizontally and vertically adjustable)
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7. depth
pulsating lumbar support, to reduce static load |
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8. adjustable
bilateral arm rests |
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9. adjustable
head restraint with lordosis pad |
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10. seat
shock absorbers to dampen frequencies between 1- 20
Hz |
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11. linear
front-back seat travel to allow differently sized drivers
to reach the pedals |
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12. seat
back damped to reduce rebounding of the torso in rear-end
impacts. |
What to look for in a good
car seat design when you buy your next car.
It's likely that most cars
on the market today won't have all of the features
listed above that are desirable in the optimal car seat,
but some will have more than others, so choose wisely. Pay
particular attention to the following 5 guidelines that
should help you to protect your back when you drive.
1) Car seat comfort
- when you sit in the car seat and you have adjusted this
to fit your body as best you can does it feel comfortable.
If not, then the car seat will probably cause you back discomfort
problems if you drive for any length of time. Bounce up
and down in the seat to see how it accommodates vibration.
Take the car on a test drive.
2) Car seat adjustments
- can you adjust all of the features of the car seat that
you want to adjust? At a minimum you should be able to adjust:
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a. Seat distance
to accommodate different leg lengths |
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b. Seat height
to accommodate different leg lengths |
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c. Backrest
angle to sit in either an upright or more reclined position
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Then you should look for
other useful adjustments:
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d. Seat tilt
to angle the front of the seat up or down so that this
doesn't press against the back of your knees |
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e. Lumbar
cushion support for the lower back. Look for a car seat
that provides you with good low back support that can
be adjusted for depth (often the seat has an inflatable
cushion) and preferably for height as well. |
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f. Headrest
for neck support |
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g. Arm rests
that are wide, cushioned and comfortable, and preferably
height adjustable. |
3) Change your posture
- remember to move your posture from time to time. Wait
until driving conditions are suitable to allow you to wriggle
in the seat to alleviate postural fatigue.
4) Take breaks - driving
is tiring work and to avoid driver fatigue and minimize
postural discomfort it is good take to fairly frequent rest
breaks that allow you to stand up and move around.
5) Seat accessories
- you can choose a variety of car seat accessories that
may improve seat comfort for you, from fleece covers to
soften the seat to bead backrests to provide for some kind
of back massage while you drive. Choose whatever you find
adds to your driving comfort.
Effects
of Driving on Posture
Maintaining
Proper Posture
EXERCISE
CAUTION: The following exercises are not recommended
Proper
Exercises For a Healthy Back and Neck
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