The differences in how triathletes
and time trialists use their aerobars are substantial,
especially in longer events such as Ironman or Half Ironman.
When a professional cyclist like Ivan Basso
or Lance Armstrong leaves the start ramp in a time trial
stage of the Tour de France they are exerting enormous
forces on the bike to get up to speed and maintain speed
on rolling terrain and in windy conditions. These professional
cyclists generate double the power output of a talented
age group triathlete. To provide a powerful base for pedaling
time trial riders try to hold their upper bodies rigid
against the pedaling forces of their legs. Pulling up
on their extensions and pushing down on their elbow pads
they are bracing their core against the forces of their
legs turning the cranks. This riding style is based in
power and relies on substantial muscular involvement of
the upper body including large muscles like the latissimus
dorsi. There is a substantial physiological cost to this
effort but in a short time trial with no run leg afterward
the time trial rider can afford the cost.
Triathletes have a different enough riding
style that they will likely not benefit from “S”
bends. While even the best triathlon cyclists like Normann
Stadler, Torbjorn Sindballe generate substantial power
they are more reliant on the aerobars for skeletal support
of the upper torso. Especially in longer events such as
Ironman triathletes tend to use the aerobars for support
of the torso. Triathletes do use the aerobars as an anchor
and fulcrum against which to brace themselves for pedaling
forces. For this reason and others the “S”
bend aerobar is not optimal for most triathlon cyclists.
From an anatomical perspective an “S”
bend aerobar is less comfortable than traditional up turned,
ski bend aero extensions. “S” bends place
a significant adduction on the inner/medial surface of
the wrist. We visited Dr. Marcus Imsande, a specialist
in treating sports injuries, to shoot X-rays of my arms
holding various bends of aerobars. The implications are
clear: “S” bends force the rider to bend the
wrist at an uncomfortable angle in order to maintain grip
on the aerobars. This causes the forearm to be less comfortable
and fatigue more quickly.
Additionally, the ergonomics of the bar-end
mounted shift lever are extremely poor in "S"
bends, with the shift lever pointing directly at the ground
in the 11 or 12 tooth cog or hardest gear position. This
orientation of the shift lever on “S” bends
makes shifting to and from the largest gears awkward and
uncomfortable. Athletes generally have to completely release
their grip of the aero extension on "S" bends
to pull the shift lever back toward them shifting to an
easier gear.
Finally, there is even a case to be made
that straighter tipped, “S” bend extensions
are more difficult to control and exert a negative affect
on bike handling. As we have observed on the road and
during indoor trainer rides athletes tend to recognize
the uncomfortable wrist postures associated with “S”
bends and release their grip on the forward, straight
extension to relax their hand and forearm. This reduces
stress on the forearm but also means the athlete no longer
has a firm grasp of the handlebars. Some athletes do this
on “S” bends without realizing it in an attempt
to make their forearms more comfortable. If the athlete
were to hit a chuckhole or have to steer quickly in an
emergency the implications of not having a firm grasp
of the handlebars are serious.
In 2007 a number of bike manufacturers have
speced “S” bend aerobars on their triathlon
bikes. This is a less than optimal configuration for most
triathletes because of the reduced forearm comfort, poor
shifter ergonomics and potentially compromised bike handling
induced by using “S” bends as opposed to up
turned ski bend extensions. All of these aerobar extensions
can be easily substituted with a more traditional, comfortable,
safer up-turned ski bend extension at a minor cost. While
many athletes may find the “S” bend aerobars
racy looking since they mimic the look of Tour de France
bikes, this is not a case of form follows function. "S"
bends do look cool and seem to present a smaller frontal
area, at least by appearances. The problem is they simply
aren't practical for most triathletes, especially newer
triathletes and long distance triathletes.
During our survey of "S" bend
aerobars we tried aerobar configurations from nearly every
manufacturer available, building up numerous bikes and
training and racing several hundred miles through 2005
and 2006 to determine the optimal configuration for the
majority of riders. While every rider and fit is unique,
more riders will benefit optimally from a traditional
upturned ski bend style aerobar than the newer "S"
bends. In the case of "S" bends, they seem to
be more fashion than function. |
