Focus on Ultralights
What Camber Can Do for Performance
- By Laurie Watanabe
- Feb 01, 2022
CHUCK AOKI: SHUTTERSTOCK/MARCO CICCOLELLA
Significant camber is clearly visible in the sports chair used by Chuck Aoki, a
three-time United States Paralympian in wheelchair rugby, seen here competing
at the Tokyo Paralympic Games last year.
Even sports fans with little understanding
wheelchair setup will immediately
notice that the rear wheels of
chairs used for rugby, basketball
or tennis look very different than
the wheels on everyday manual
They’re seeing camber, what
United Spinal Association defines as
“an angling that brings the top of the
wheels closer to each other” (spinalcord.org). With camber applied, a
chair’s rear wheels are no longer
perpendicular to the ground.
Camber can offer many functional
benefits… but as with all wheelchair
setup choices, adding camber
to a system is a matter of careful
Less Energy & Effort Expended
Lauren Rosen, PT, MPT, MSMS, ATP/SMS, is the Program Coordinator
for the Motion Analysis Center at
St. Joseph’s Children’s Hospital of
“It’s the angle between the top
of the wheel and the bottom of the
wheel,” Rosen said, in explaining
camber. “Camber helps with stability,
and it helps with turns. That’s why
when you see the sports chairs —
tennis, basketball, rugby — they all
have a huge amount of camber in
them. Because that makes you super
stable, and that makes you turn on a
dime. Those are two things you need
for playing all of those sports, especially
basketball and rugby, where
there’s chair-to-chair contact.”
But wheelchair stability is crucial to
efficiency and function, even if your
clients aren’t aiming to compete in
“It makes the chair feel more
stable laterally,” Rosen said. “It’s not
going to stop fore/aft tipping; that’s
about center of gravity and casters,
etc. But camber makes the chair
more stable laterally, so if I need to
pick something up off the ground or
reach to the side, it makes my chair
Camber also makes turning
the wheelchair a more effortless
endeavor. “It puts less of the tire in
contact with the ground, so it turns
easier,” Rosen said.
How Much Camber Is Ideal?
So if adding camber to a system
makes the wheelchair easier to turn
and also makes it laterally more
stable, what’s the down side?
Well, splaying the rear wheels
outward can make a wheelchair
substantially wider. The more camber
it has, the wider the chair gets.
Camber is measured in degrees,
and Rosen pointed out, “[In sports
chairs], it’s like 15° or 20°. It’s a
significant amount. For a lot of those
guys and girls, they have to take at
least one if not both wheels off to get
through a door.
“That’s why you see a lot of them
bringing their day chair and their
rugby chair, because that rugby
chair won’t go everywhere. That’s
why they don’t leave their day chair
at home and just travel in the rugby
chair, because it’s ridiculous to try to
make it through doors in something
with that much camber.”
Larger amounts of camber can
interfere with accessibility. Smaller
amounts of camber, though, can
offer multiple benefits without
causing doorway problems.
“The only reason I would ever give somebody a chair with 0° camber is if I’m worried about
them getting through a door — if they’re wide and their
chair is wide, and I’m worried about door access,” Rosen
said. Basically, everybody else she sets up in her clinic
“gets 2° to 4° of camber because the chair rolls better.
The wheels are closer to your body, so you have better
wheel access. It just makes for a more stable base.”
Such modest amounts of camber, Rosen added, are
not readily noticeable, unless you know what to look for.
“With 2° to 4° of camber — you really don’t see it. It’s not
obvious that there’s camber in the wheels, unless you’re
actually specifically looking. Anybody who would look at
the chair would not think there was camber at 2° or 4°.
“But if you push a chair with 0°, 2°, and 4° of camber,
you’d feel the difference.”
Because Everything Matters in Manual
Camber can make those rear wheels easier to reach,
a real benefit especially to very young ultralightweight
wheelchair users with shorter arms.
“If I really know there’s never going to be a door
access issue because you’re super small, I’ll go with 4°
[of camber], because you’ll come back and tell me
it’s easier to push,” Rosen said. “It gets the wheel a little
closer to him up at the top so he’s not having to abduct
so much, and it’s an easier turn. If I make [an adult
wheelchair] just a smidgen too wide, you can’t get into
your house. In kids’ [wheelchairs], I don’t have to think
Despite its great potential impact, Rosen added that
camber is just one element in the science and art of optimally
setting up an ultralightweight wheelchair, whether it’s
for a world-class athlete, a weekend warrior, or a giggling
preschooler whose main goal is keeping up with siblings.
“Some of it being easier to push is [due to] the rest of
my setup,” she said.
“Everything matters on a manual chair. I can put your
center of gravity in a great place, but if I give you no
camber, you’re going to feel like it’s hard to push. If I put
your seat depth in the wrong place and make you sit
uncomfortably, having perfect camber doesn’t make a
“I can give you the lightest-weight chair on the market,
whatever that is today, and if I don’t set up everything
right, it can feel just as bad as pushing a steel chair.”
This article originally appeared in the Jan/Feb 2022 issue of Mobility Management.
Laurie Watanabe is the editor of Mobility Management. She can be reached at firstname.lastname@example.org.