what's the lowest wrote:
I am likely unfair and maybe wrong in my thinking about what mileage people normally run. Is 25 miles a week a lot of running for most people? What is the minimum mileage someone can run per week that you would consider that person to be a serious runner?
The answer to the question "are you a serious runner?" is "are you committed to your performance?" and time spent is a better marker than mileage.
You mileage approach is pretty crude, since it doesn't include everything about a runner's commitment. I know an older who runs an 10k+ a day no matter what and a long run on Sundays, maybe 50-60 mpw. He only races marathons although pretty casually, always over 3:00 and he is pretty nonchalant it all. Another masters runner I know probably never goes over 30mpw, yet he is at the track doing drills, weights, exercises etc 60-90 minutes every day. He is one of the best in the world for his event and age.
I would think that an hour a day every day, even almost every day, would qualify as a serious interest for a recreational pursuit. (And yes, this is a recreational pursuit for most of us. Not matter how "serious" we like to call ourselves, a guy training to run a 5k in under 20:00 or 19:00 or even 16:00 is a hobby.)
Someone running 25 miles is typically doing that in 5-6 runs. I'll use 5 for the easy numbers.
Let's say 5 days running per week, each with a 5-miler. (Again, just for simplicity.)
If those miles are run at 8:00/mile (probably that's a quick estimate, since 13:45 LetsRunners brag about their 9:00+ easy miles), you are looking at 40 minutes of moving time. Add into that the stretching and ancillary exercises most people are doing, and you are easily looking at an hour commitment 4 weekdays and 1 weekend day each week. (Not even getting into the time getting to tracks/trails/gyms, which many would be doing.)
I think that's fairly serious. What else do you do that much during the week, other than biological functions, parenting and paid work?