Many of the root causes of most running injuries are determined by how much a runner pronates.
Pronation refers to the side-to-side motions of the back of the foot during the touchdown
and stance phases of both walking and running.
The functional relevance of pronation in walking and running is to provide mechanical support
as well as impact protection however too much pronation during running may actually work
against your injury prevention efforts as many studies have discovered that excessive
pronation or overpronation or hyperpronation during running may amplify impact and have
a profound ripple effect up the leg that may increase torque, rotation and bending strain
to reach a level of an injury on the Achilles tendon the shins and the knees.
Basically with overpronation during running the foot wrestles with the ground too intensively
because the foot is shifting in extreme positions on the ground and according to much of the
research to date the list of things that can go wrong
with overpronation regarding causing injury when running outweighs to that of running
with less pronation or more controlled pronation.
Some studies specifically implicate that foot strike pattern during running may ultimately
influence pronation patterns such that the foot may undergo a different pronation pattern
in heel strike running than in forefoot strike running and this difference may yield clues
about more of an exact relation between foot strike pattern and injury in running.
In fact, several studies have connected heel strike running to pushing pronation out of
a safer range which may overstress the lower leg more so than in forefoot strike running.
For instance, some lines of research which are linked down below this video in the description
box found that during the stance phase of heel strike running the forefoot or the front
of the foot rapidly rotated outward away from the midline as the body weight passed over
the foot from heel-to-toe.
This also caused the arch to fully collapse which forced the medial border of the foot
(which is the inner border of the foot extending from the heel to the big toe) to absorb excessive
levels of abnormal stress until the forefoot thrusts the body forward.
This excessive abnormal forefoot stress due to the arch collapsing too much during the
pronation phase or the stance phase in heel strike running also increased frictional forces
on the foot with the ground and taken together, the cumulative effect of these physical stressors
at the feet amplified impact stress at the ankles and the shins whereby this additional
impact stress loading across the lower leg may increase the risk for medial shin splints.
This finding suggests that one way or another, the pronation pattern in heel strike running
may not really pay off for injury prevention because when the arch fully collapses like
it does when the body-weight travels from heel-to-toe may lead to abnormal foot postures
that may project heavier mechanical stress and strain on the foot and leg and the hyper
pronation pattern of the foot in this way, in heel strike running, may result in insufficient
impact absorption which may result in higher rates of impact stress across multiple sites
on the lower leg, namely the shins and may essentially keep injuries going.
However, landing with a forefoot strike while running may prevent pronation from going wrong
because a shorter ground-contact time period of the foot is a natural complement response
of landing mforefoot-first during running.
So, there isn't a lot of time for pronatory mobility impairments of the foot to kick in
like in heel strike running where in heel strike running, the foot spends more time
on the ground which may essentially free up more time for abnormal foot motions and postures
to take hold, but what is more is that by no means are the natural pronation patterns
of the foot similar between heel strike running and forefoot strike running.
The pronation patterns between the two foot strike types in running are very different
which is why there's different varieties and intensities of impact force variables.
In fact, I did a video, which is linked down below this video in the description box, on
how the foot may operate from a safer pronatory pattern in forefoot strike running which may
be more protective against so many negative injuries outcomes as compared with heel strike
running.
But, as for how the pronation pattern in forefoot strike running may ease mechanical burdens
on these shins is that the same study found the medial aspect of the foot in forefoot
running didn't endure a rise in abnormal loading during the stance phase on account of there
was just less overall support demands required of the medial foot during the support phase
in forefoot strike running making that part of the foot less prone to overuse and overloading
which in turn may make it easier to avoid medial shin splints as compared with heel
strike running.
Overall this kind of data makes it more clear that foot strike pattern in running may strongly
influence injury by affecting the way the foot pronates and therefore affects the way
the foot contributes to impact absorption and mechanical stability such that the movement
path of the foot in heel strike running may force certain motions and postures of the
foot that may put the leg under more pressure than in forefoot strike running and because
of the notable difference in pronation where the movement path of the foot in forefoot
running seems to do a lot more to limit negative interactions of the foot with the ground is
also why there's a very good reason forefoot strike running seems to be gaining
the upper in paying off long-term for injury prevention over heel strike running.
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on forefoot strike running versus heel strike running.
Thank you so much for listening and watching.
Have fun out there on the roads and trails.
Bye for now!