But who bears the brunt of the impact? The article/paper seems
to suggest that the quads/hammies/calves/other muscles bear the
load more than the joint
From the pubmed paper
Beside the changes in the electromyographic activity of the
muscles, the anterior compartment muscles of the calf undergo a
concentric contracture at the time of initial floor contact during
running and sprinting but undergo an eccentric contraction during
walking.
From the 2nd article
First of all, think about jogging. Moving slowly forward,
planting your feet flat (or heel first), not much motion in your
upper body. You've felt it yourself or seen other people 'feeling
it' as they plod around.
This type of motion does NOT take advantage of your biology. In
fact, it leads to a huge amount of repetitive impact and stress on
your joints. This is why so many people have back and knee problems
when they start jogging to get in shape.
Sprinting, on the other hand, takes full advantage of the built in
'shock absorbers' and stabilizers in your body. The tendons and
ligaments in your legs, the arches in your feet, the surface area
of your joints, our big buhts, the width of your shoulders, the
narrowness of your hips, your head - all built to run fast, not
jog.
Not only that, the proper planting of your feet while sprinting
increases the shock absorbtion even more - saving your body from
nagging pain and injury in the process.
