I don't know how you can claim that running on hard pavement is good for the body, with comparable cardio as a control.
I strongly doubt that this control model is correct if the recommended adjustment is to discard the association between e.g. patellar tendinitis and patellofemoral pain syndrome and running surface hardness. Still, the guidelines should be to avoid road runs because they certainly exacerbate symptoms of such injuries or disorders.
Also I imagine that trail running might raise potential to land awkwardly because the ground is all sorts of uneven. Pavement on the other hand is pretty predictable.
They each have their charms, I suppose.
As for now. I'm kind of 50/50 or maybe 60/40 in favour of a regular old road vs trails. I much prefer a road to something like a beach. Having to compensate for the constantly giving, lumpy ground that is sand, is kinda meh. I also seem to remember a study that found it was actually worse for injury risk, to run on sand.
Landing on the ball of the foot means your leg isn't hyper extended, which means the impact is diffused since the knee and hip aren't completely straight at the moment of the strike. The whole hyper extended leg and heel-strike thing seems to be a consequence of raised-heel shoes. See my other post on this thread. Particularly the Harvard link.
Without shoes the first impact is the ball, followed by the toes, then the heel, last (or sometimes not at all). The impact on the joints is actually lower this way than heel-striking with a raised heel shoe. You can kinda just try this, even by jumping in place and landing on your heel with a shoe, vs landing on the balls of your feet.
In middle school, on an asphalt track with painted lines, I took out a hurdle and a chunk of my hip learning to run hurdles.
Sometimes people fall where they're running.
The roughness of a soft track also scrapes but it's definitely nicer than road runs IMHO.
I really doubt that we're evolutionarily tuned for running on hard surfaces.
So, the control model for this study
For how many generations have humans had what kinds of shoes
Seems apparent to me that shoes vastly alter the mechanics of a step. Just try sprinting at full speed for 20 meters or so, maybe indoors or something, if the pavement is intimidating. You might notice it feels very different. Much easier on the joints.
I say sprint because I imagine that would reinforce the instinct to ball-strike right off the bat. At least it was that way for me.
All that said, apparently some people still heel-strike without shoes and have to unlearn doing so. Also, trying to force ball-strikes with raised-heel shoes, when I was in my mid 20s, gave me terrible shin pain.
I also found the lack of a jolt from ball-striking, makes for easier breathing.
It may be intimidating at first, there are lots of little foot/ankle muscles that take time to get built, not to mention calluses that are like pads, but it certainly feels easier on the joints.
FWIW, I've had a bum knee ever since being pushed to the ground in gr4 so the fact it's no worse for wear should count for something. Of course my word alone means nothing though. Maybe take Harvard's.
https://scholar.harvard.edu/files/dlieberman/files/2012c.pdf
Anyway, I wonder if the running-knee-scare from yesteryear was because of a difference in shoe design.
Edited to add:
Oh yeah, I also want to add that barefoot running makes a MASSIVE difference in preventing ankle-roll injuries. For some reason I got really prone to rolling in my early/mid 20s or so. After running barefoot, it pretty much stopped outright.
The one or two times I did ankle-roll, (YAY work boots), I just shrugged it off and continued on, feeling nothing about 20 min later. This vs getting all swollen and not being able to walk for a week.
I'm pretty sure I've never rolled without shoes on. It's another one of those things that kind of seems evident. That is, that the mechanics of shoes hinder your ability to prevent rolling.
With shoes, you kind of lose the ability to deliberately pronate the ankle/heel, to micro-adjust balance, while keeping the ball and toes firmly planted to the ground. It seems to me, this is because the shoe heels are flat where our own heels are rounded. Also shoes are usually pretty stiff while feet can twist a little bit.
Qem•7mo ago
jfengel•7mo ago
If you locked your knees out, you would have to take the strain in your cartilage. That would hurt a lot.
More weight does put more strain on those ligaments, and that can result in an injury. And you do wear your shoes out more quickly, which causes you to land unevenly and puts lateral strain on ligaments not designed to take it. The results are repetitive stress injuries that can take some time to heal.
But if you're practicing good form, increase mileage gradually, and (ideally) do some strength training, overweight runners can run forever.