Why do my knees feel fine after a marathon, but not a 7 miler?

Question

I ran the SF marathon and my knees and body felt great afterwards, yet I wake up this morning after jogging 7 the night before and my knees are barking bad! The shorter runs seem to have more an effect on my knees than the long 20+ runs.

Answer 1

I don't know how that feels seeing as i have never, nor could run 7 miles!

Answer 2

One possibility is when you are running faster for that shorter distance, you are moving your legs faster which will put more pressure on your kness. And if you run downhill or do a lot of turns, it puts a lot of pressure on your knees. Usually in a marathon, they won't make you run a lot of hills so that could be the reason.

Answer 3

HS, I really don't know.  How long ago did you do the marathon, versus the 7 miler?  Don't know how old you are either.  The condition is called "delayed onset" muscle pain?  It can be 48 hours before the lactic acid and your body, really let you know of the damage that needs healing?  

I'm no expert, but if your over 35 years, it ain't the distance your running? It's the "frequency" of your runs. It has to do with "recovery".   Again, I'm no expert, but instead of running 4 miles "every day", running 8 miles "twice a week"; probably is more beneficial??  Everyday, would be 28 miles a week?  Eight twice a week would only be 16?  Oddly enough, when you'd run those occasional "marathons", on the twice a week at 8 miles, you'll do much better.  

Answer 4

I have a similar problem. Was the surface you were running on different? Were there more turns? There's a lot of factors you have to take into consideration. It could also be that the marathon pace is easier on your knees than is the 7 miles.