HEALTH
& FITNESS
The
Anatomy of a Runner
By Patrick Milroy
Knowledge is the power to reducing your injury risk.
Join us on a tour of the body’s components, and look at how they become
damaged.
Bones:
Bones are essentially the scaffolding of the body,
and although they have some flexibility in childhood, this largely disappears
with age. Structurally, the outer bone, which is thick and dense, covers an
inner honeycomb matrix of porous bone, which is suffused with marrow and blood
vessels to provide nutrition. Varying in length from a few millimetres to over
50cm, every bone has evolved to maximise lightness, efficiency and strength.
Bones are surrounded by a layer of fibrous tissue, the periosteum, which, thanks
to a particularly good nerve supply, is very sensitive.
Common
damage:
When you break a bone, you also damage the blood vessels nearby, which behave
as we’ve just explained. When bones heal, they form a tissue called callus,
which remoulds into normal bone but is often thicker and stronger than the
original bone, as though to prevent another fracture should you have a similar
accident again.
Runners are plagued by the stress fracture – to
picture one, think of a crack in a china cup. The fracture occurs as a result
of overuse and repeated stress to a bone, and the broken surfaces are only held
together by surface tension and the surrounding tissues. You’ll probably become
aware of a stress fracture by experiencing ‘crescendo pain’, which starts when you
run, increases to reach a peak, and only eases when you stop.
A doctor will often have to make a diagnosis from
your history, as x-rays show little in the early stages, and scans and other
investigations are extremely expensive. The risk with a stress fracture is that
a minor knock may upset the unsteady equilibrium and cause a complete fracture,
which takes twice as long to heal.
Joints:
The joints between bones are limited in their
direction and range of movement by the shape of the adjoining surfaces. These
are covered by cartilage, the smooth finish of which is lubricated by synovial
fluid, secreted within the joint to give almost frictionless movement.
According to the laws of physics and levers, any reduction in a joint’s range
or movability will decrease its efficiency, and from our point of view can only
slow the runner.
Muscles:
Muscles come in various forms, but those which link
bone are composed of microscopically striated (streaked) tissues, which contain
fast- or slow-twitch fibres. If the muscle is joined to bone at each end,
muscle contraction will bring the bones together, and an opposing single muscle
or group of muscles will reverse the action when it receives the signal to do
so.
Common
damage:
Muscles are richly supplied with blood vessels, so they bleed freely when
injured, but heal rapidly. If you completely rupture a muscle, others will
often take over its role and allow you to function reasonably normally, despite
the fact that your limbs will look unbalanced. These muscles will strengthen
and grow, so you will lose little – if any – strength.
It is important not to work an injured muscle too
vigorously in the early stages, as fresh bleeding can cause the bruise to
calcify and lose elasticity.
Circulation:
Body tissues receive oxygen and other nutrients
through arteries. These, like the branches of a tree, divide into ever-smaller
arterioles and ultimately into capillaries, where the exchange of nutrients and
waste can occur. The blood returns through venules and veins in reverse pattern
to the heart, which pumps it to the lungs for re-oxygenation and then returns
it to the heart again to complete the cycle. Arteries contain muscle within
their walls, and the blood in them is under much higher pressure than that
within the venous system. This is particularly relevant in understanding the
injury and healing cycles.
Common
damage:
If you damage the inside or outside of blood vessels by stretching them beyond
their elastic limit, you’ll create faults in their walls, which will bleed. The
volume of blood lost will depend on the extent of the damage and the pressure
behind and opposing it. If you bleed from an artery, you’ll almost invariably
lose more blood than if you bleed from a vein, and warmer areas – in which the
vessels are dilated – bleed more than cold ones. The greater the amount of
bleeding, the more the damage, and hence the longer before healing occurs.
The clotting process begins from the moment that
bleeding occurs, as elements within the blood congeal and form fibrous scar tissue.
This eventually reorganises itself, and the tissues can become almost as good
as new, although much depends on how you approach rehabilitation.
In general, an area that is richly supplied by blood
vessels will bleed more freely, but will heal most completely and rapidly.
Ligaments and
Tendons
Ligaments are formed of fibrous collagen and serve to
loosely join bones. They are generally inelastic and unstretchable. Only if
subjected to prolonged strain will they elongate, which results in hyper
mobility. The classic runner’s example is the flat foot, which inevitably
worsens with both increasing age and mileage!
As muscles tend to be bulky, tendons have often
evolved at their extremes to transmit muscle pull in small or awkward spaces,
or even around corners. In the latter instance, to prevent friction, they may
have a sheath of synovium which provides lubrication. White and shiny but
thinner than muscle, tendons are immensely strong but suffer from a relatively
poor blood supply, which can delay or prevent healing if they are damaged.
Common
damage:
Injuries to ligaments and tendons tend to behave in much the same way as muscle
injuries, though they’re slower to heal because of poorer blood supplies. This
causes special problems for runners, and healing and rehabilitation must be
carefully supervised to optimise recovery times.
Nerves:
The most convenient way to picture the nervous system
is as a computer with the brain at its centre. The functional units of the
system are neurones, each of which can only conduct impulses in one direction –
either towards the brain for sensation, or away for motor purposes such as
driving the legs. Neurones of both types may both be contained within a single
nerve. Many bodily functions, such as heart rate and digestion, are
involuntarily controlled by what are called the sympathetic and
para-sympathetic nervous systems. The classic example of their function is the
urge to evacuate the bowels prior to a race!
Common
damage:
A nerve containing both motor and sensory fibres may
be completely severed in a deep body wound, and all the body parts supplied by
that nerve away from the spine will be without pain but paralysed. More
commonly, though, nerves can become trapped or bruised, which causes pain,
numbness or weakness. Although full recovery will occur if the pressure on the
nerve is relieved, at one millimetre per day, it may take several weeks!
Submitted by: Mick Edge
Submitted: 26th
January 2008
Arch Pain/Arch Strain
Definition
The term arch pain (often referred to as arch
strain) refers to an inflammation and/or burning sensation at the arch of the
foot.
Cause
There are many different factors that can cause
arch pain. A structural imbalance or an injury to the foot can often be the
direct cause. However, most frequently the cause is a common condition called
Plantar Fasciitis.
The
plantar fascia is a broad band of fibrous tissue located along the bottom
surface of the foot that runs from the heel to the forefoot. Excessive
stretching of the plantar fascia, usually due to over-pronation (flat feet),
causes Plantar Fasciitis.
The
inflammation caused by the plantar fascia being stretched away from the heel
often leads to pain in the heel and arch areas. The pain is often extreme in
the morning when an individual first gets out of bed or after a prolonged
period of rest.
If this condition is left untreated and strain
on the longitudinal arch continues, a bony protrusion may develop, known as a
heel spur. It is important to treat the condition promptly before it worsens.
Treatment and Prevention
This
is a common foot condition that can be easily treated. If you suffer from arch
pain avoid high-heeled shoes whenever possible. Try to choose footwear with a
reasonable heel, soft leather uppers, shock absorbing soles and removable foot
insoles. When the arch pain is pronation related (flat feet), an orthotic
designed with a medial heel post and proper arch support is recommended for
treating the pain. This type of orthotic will control over-pronation, support
the arch and provide the necessary relief.
If the problem persists,
consult your foot doctor.
Foot Health Information
Provided By: foot.com
Athlete's Foot
Definition
Athlete's foot is a fungal infection that causes
red, dry, flaking skin, sometimes accompanied by pain or itching. The condition
usually occurs between the toes or on the soles or sides of the feet. In its
acute stage, the infected foot exhibits blisters that itch or "weep."
Athlete's Foot can spread to the toenails, causing chronic fungal infections. Often
when a patient thinks the feet are only dry and cracking, Athlete's Foot is
responsible for the problem.
Cause
Fungal infections like Athlete's Foot are often
contracted in showers, gyms, dressing rooms, swimming pool lockers, or other
warm, damp areas where fungus can thrive. The name of the condition comes from
the fact that athletes spend the most time in these environments and therefore
are at a higher risk of fungal infection.
Once
fungal spores are present on the feet, they can enter fissures or sores and
remain there to spread, unless the feet are carefully washed and thoroughly
dried after exposure.
Athlete's
Foot can spread from the toes to the toenails. If the patient touches or
scratches the infection and then touches other parts of the body, the fungus
can spread to fingernails or other parts of the body, including the groin or
underarms.
Like
any foot condition, Athlete's Foot is of special concern to people with
diabetes and compromised immune systems who are more susceptible to developing
infections that can lead to serious medical problems.
Treatment and Prevention
Vigilant foot hygiene can prevent Athlete's Foot. Daily washing of the
feet with soap and water followed by thorough drying, especially between the
toes, is important. Wearing dry, airy shoes and socks, not borrowing footwear
from others, avoiding tight hosiery and using foot powder all help to keep the
feet dry and infection-free. When using public showers or pool areas it is a
good idea to wear protective shoes.
Once
an infection has occurred, it is important to see a doctor, have the problem
diagnosed correctly, and treat it promptly. Fungal infections can be stubborn
and difficult to treat, and can become chronic. Treatment plans include
prescription antifungal medications, either topical or oral, and continued
attention to keeping the feet clean and dry.
Continue
to consult with your foot doctor until the problem is eradicated.
Foot Health Information
Provided By: foot.com