Your Body and Your Bike
We understand that your time is valuable. We feel that its important
for you to know a few basic, but crucial concepts regarding your
pedal stroke. Please take time to read the following information
and we know it will increase your perspective on what we do!
The lower extremity is dedicated to the vital tasks of weight bearing
and ambulating; its health is essential to normal and efficient
daily functioning. The same holds true for your pedal stroke. Any
obvious deformity of the extremity may affect your pedal stroke!
The ankle joint consists of three bones, the medial (inside) malleolus
(distal end of the tibia), the lateral (outside) malleolus (distal
end of the fibula) and the wedge shaped talus. The ankle gets its
stability from the three bones, ligaments and tendons that surround
structure of the foot is determined by bones of the tarsal and metatarsals
(forefoot). These bones form the arches of the foot which are also
supported by many ligaments and tendons. It is know that a (high
arched foot tends to be very rigid) and not very good at absorbing
shocks through the foot. The (flat foot is also poor at shock absorption
because it collapses) during contact. Providing longitudinal arch
support for both of these configurations can make a difference since
you only make contact at a very small area of the pedal.
Take a look at
a sample "Help" file from the fit solution!
Read about Soles Footbed
in the News - World's Only Dynamically Fitting Footbed!
knee is the largest synovial joint in the body. It involves three
bones: femur, tibia and the patella and it should remain flexed
during all components of the pedal stroke. The meniscus is a special
type of connective tissue that provides shock absorption and increase
contact surface at the knee joint. The knee joint relies primarily
on ligaments for stability, sideways, forward or backwards and also
rotational stability. The strongest muscles in the body, the quadriceps
(thigh) muscles cross the knee and attach onto the tibia (tibial
tubercle) to extend the knee. The hamstring muscles cross the knee
joint at the back and function to flex the knee. Medial and lateral
rotation can only occur when the leg is flexed. Perfect alignment
is needed to protect this joint from excessive movement.
The pelvis and trunk shift laterally approximately one inch to
the weight-bearing side during normal gait to center the weight
over the hip. This movement is also needed as your in the saddle.
By having a saddle too high, you reduce this needed lateral movement.
The average length of a step is approximately 15 inches. With pain,
advancing age, fatigue, or problems of the lower extremity, the
length of steps may decrease. The same is true for the pedal stroke.
e.g. 175mm cranks times 2 equals about 14 inches. A smaller crank
can reduce stress on the lower extremity for any of the above reasons.
The average adult walks at a cadence of approx. 90 to 120 steps
per minute. This holds true for your pedal stroke! Changes in this
smooth, coordinated pattern markedly reduce efficiency and greatly
increase the energy cost. With advancing age, fatigue, the number
of steps per minute decreases.
During the swing phase, the pelvis rotates 40-degrees forward,
while the hip joint on the opposite extremity ( which is in stance
phase) acts as the fulcrum for rotation. Having the wrong location
of saddle can reduce this needed rotation movement.
dorsiflexors of the foot (the tibialis anterior, extensor digitorum
longus, and extensor hallucis longus) permit the foot to move into
plantar flexion through eccentric elongation so that the foot flattens
smoothly. The wrong pedal stroke can cause the eccentric elongation
of any of these muscles to be torn. Eccentric elongation is when
you for the most part tear your muscles. This also affect your timing.
At mid stance, the foot weight is borne evenly on all aspects of
the foot. Those with fallen transverse arches of the forefoot may
develop painful calluses over the metatarsal heads. Any rubbing
against the shoe can cause "Corns". A footbed helps spread the foot
weight evenly on all aspects of the foot. It also helps hold the
foot where it should be within the pedal stroke. A poor fitting
shoe will cause you problems.
The toes need to grip the ground. Without a custom footbed you
can't do this. Knee, the quadriceps muscles contract to hold the
knee stable, since it is not normally straight. Weakened quadriceps
may result in excessive flexion and a relatively unstable knee.
Having a saddle too far forward causes a unstable knee. And having
a saddle too low can cause unneeded wear. The knee is susceptible
to injury primarily because it is subject to maximum stress, located
as it is at the end of two long lever arms, the tibia and the femur.
It is not protected by layers of fat or muscle and it is exposed
both environmentally and anatomically, which contributes to its
high incidence of injury. The bony contours of the knee are prominent
and easy to find!