Doctors: Just 10,000 steps of walking every day is fine too!
Doctors: Ok, how about 8,000 steps only once or twice a week. Can you do that?
Doctors: For the love of god, please just get off the couch every once in a while...
It took the covid lockdowns for me to discover that I actually enjoy this stuff. I put some headphones on and listen some podcasts. I can't focus on a podcast at home or while working. I get distracted or I start doing other things and lose focus. When I walk, I listen. So when I want to listen to a podcast, I just go for a walk now. And if it's a long podcast, I just walk a bit longer.
Anyway, this stuff does seem to work for me. And I don't even mind doing it. Win win.
Although the studies I glanced at say something like:
<2000 steps, couch potato, certain doom
>2000 greatest reduction in risk
6,000–9,000 steps per day 50% reduced risk of CVD for 60+ year olds <=== you want to get used to this as your baseline to be a healthy silver fox
10k steps, marketing for original pedometer
20k steps, best way to lose weight, almost nobody does this daily :)
Here is a depressing video High School Fitness (1962): https://www.youtube.com/watch?v=NGa6BPj3Mcw
And the easiest one to compare is of course US basic training standards that have gone down each time they have been revised since WWII.
Meanwhile this is more like the 5th study I've heard of which talks about some measure of exercise at least 1-2 times a week, like 20+ minutes of cycling.
I don't think many people need to worry about limb damage from over-walking, and the ones who have already experienced limb damage need to find alternative exercise rather than minmaxing steps...
There's even evidence that distance running strengthens your knees, contrary to common knowledge. https://archive.ph/utsUF
Worrying about too much exercise for the average person is like worrying about drinking too much water on a desert hike.
You really have to overdo it to get to negative consequences of light physical activities such as walking. Just talking a one hour walk every day surely doesn't get you anywhere near the red zone, provided you're otherwise reasonably healthy.
That said, we are discussing this in the context of walking a bit more, which should be very well-tolerated for pretty much everyone as long as they don’t have other significant health problems and work up gradually. For example, if you take 1000 steps a day, space out the increase by each week increasing your daily steps by 500-1000 steps a day until you reach 10000 steps a day over the course of a few months (temporarily pause or reverse the increases if you see anything other than passing muscular discomfort).
This also explains how ultramarathon (or other “extreme” physical activities) can be tolerated without much issue—bodies are very good at adapting to the loads that are placed on them as long as that increase is gradual and they have enough food and rest to rebuild after particularly intense bouts of activity.
A further corollary is that over the long term, being sedentary is not well-tolerated at all, so maintaining a certain baseline level of physical activity is definitely a better idea and as long as your body isn’t giving you any feedback to the contrary, you shouldn’t avoid high loads or intense activity just out of abstract fear of injury.
But as HN likes to day, the plural of anecdote is not data. Nor the dual: but for what it's worth, I haven't run a marathon since 1986, not have I stopped running.