I’ve been reading a few articles by Paul Ingraham about muscles, and stretching, and injuries, and such. Among the things that really struck me was his discussion of the Anterior Tibialis. In it, he describes the function of the anterior tibialis: eccentric contractions to hold up the foot and prevent it from flapping down to the ground after the heelstrike.
After the heelstrike.
I might just quote a chunk, as it’s interesting:
We usually think of the shin as a bony place, but in fact there is a good-sized muscle on the lateral face of the shin: the tibialis anterior muscle. The tibialis muscle works almost alone: it is the only muscle that strongly lifts the foot. Functionally, its major job is not to shorten, but to lengthen in a controlled way: to gently lower the forefoot after the heel strikes the ground. This requires an eccentric contraction — the muscle contracts while lengthening, as your biceps does when you lower a barbell.
Without the tibialis anterior’s powerful and well-coordinated eccentric contractions, your foot would slap ungracefully onto the ground with every step. On hard surfaces like concrete, the strain of preventing foot slapping is immense. For runners, that strain is often how shin splints usually begin, and is one of the main reasons to avoid hard-surface running. Eccentric contractions are known to cause additional muscle soreness after exercise, which is why the shin muscle tends to get really sore after running hard — and why the muscle tends to develop large, chronic trigger points.
He mentions (perhaps in another article) that this function is even more important - and stressing for the muscle - when running downhill, as the foot has to be controlled (using those eccentric contractions) through a greater distance. This led me to think about my efforts at running when I was in my mid-to-late teens. Then, I used to get what I now recognise to have been compartment syndrome in the anterior tibialis (not acute compartment syndrome; I still have my legs…). That was always particularly pronounced during and after running downhill.
This last few months of running, I’ve not had that at all. Not the slightest hint of it. I’ve had other things, for sure, but not that. I’ve even had shin pain (which is all that “shin splints” actually means), but not in the anterior tibialis.
Even running downhill
Now, I dislike running downhill; I’m not good at it; I find it uncomfortable - but it doesn’t hurt my shins. So what’s the difference nowadays?
I don’t land on my heel (anymore); I land on my forefoot or midfoot. So my foot doesn’t need that final bit of holding up by the tibialis. Certainly it needs holding up through the stride, but there’s probably not the eccentric contractions involved - at least not to anything like the same degree.
To me (and I should emphasise this is simply my own logical extrapolation based on Ingraham’s description of the tibialis’ function, and my own anecdotal experience) it seems very plausible that the reason I was getting that compartment syndrome was that my running style at the time required of the anterior tibialis a lot of eccentric contractions, and my style now does not. Given Ingraham’s description of the function of those eccentric contractions, I am further convinced I was heel-striking then, and am not now.
And further convinced that habitual and consistent heel-striking is A. Bad. Thing. It may well be true that over striding is worse than heel striking. It may even be true, as Ingraham contends, that the total amount of exercise is more important than either. But given that a heelstrike will require this eccentric effort from the tibialis, and a forefoot strike will not, and that the tibialis’ small fascia sheath renders it particularly susceptible to compartment syndrome, I submit that it makes good sense to avoid hitting the ground with your heel first.
The current faddishness of “barefoot running” notwithstanding, our gait evolved along with our feet - our bare feet - and I submit that is likely therefore that the way we run barefoot is overall the best. And I challenge anyone to go and heelstrike barefoot and not regret it. xP