Other options are bad knees (unlikely, honestly. Not many people have knees that are so genuinely shot that they can't run, unless they're former paratroopers or are very years old)
Or, if you're carrying a lot of extra weight (backpack full of water? I don't know, people do whatever they do), that'll hurt.
Since you're talking about running in the woods, it's almost definitely not the sidewalk, but, some people need to build up their muscles and tendons by going from softer surfaces (not so soft like sand, but grass) to ashphalt, to concrete.
Instead, they're focusing on the athletic performance aspect, to the point that, near as I can tell, they're outright fanning the flames of controversy around the idea that these shoes are unfairly fast.
The study itself says:
> This was an observational study where people chose whether or not they wanted to run; therefore there is always the possibility that people stopped running because they had knee pain.
That's a pretty big flaw in their study.
All runners who run regularly will eventually develop knee or ankle pain. It's sort of normal for semi-serious distance runners to own a pair of crutches. I'm not saying all of them, but, if you need a pair of crutches, ask your friends who run and one of them will have a pair.
But, your knee can hurt for a while without it turning into joint problems.
> This was an observational study where people chose whether or not they wanted to run; therefore there is always the possibility that people stopped running because they had knee pain. As such, we cannot comment upon the influence of compulsory running on overall knee health.
so... forced running might cause osteoarthritis. But, if you feel like going for a run and it doesn't hurt, it's not going to cause joint problems.
> Our study findings add to the existing literature by including a large sample within which we were able to assess the influence of running in people who participated in running for shorter amounts of time and perhaps stopped running in a cohort that had high quality of assessments of symptoms and standardized radiographs. We found that runners in this group were not at a higher risk for symptomatic knee OA.
Overuse injuries got a bunch of people I knew. They'd use crutches to speed recovery up a bit, or to get around if it was bad enough.
> > This was an observational study where people chose whether or not they wanted to run; therefore there is always the possibility that people stopped running because they had knee pain.
> That's a pretty big flaw in their study.
How do you figure? These people are accounted for in the data. Regardless of why people stopped running, they have better outcomes than never-runners. E.g.:
> Any history of running was associated with less frequent knee pain (table 2) in the unadjusted and adjusted models compared to those who never ran.
There are exercises, stretches and techniques you can learn, as well as products you can buy that you aren't going to find at a Foot Locker.