Yes, we are all different, and some adaptations take longer.
My guess is your challenge is more in your brain than your body.
Sounds like you are used to going fast, so slogging through 3 or more 12-13 minute miles doesn't sound good to you. But if you are gasping after 2 miles, you are running too fast. If you can comfortably do the distance with intervals, then yes - slow your pace so you can do the full distance. The speed will come later.
And it seems too that you have convinced yourself that you can't do more than 2 miles - untraining your brain is often more difficult than training your body. Stop focusing on the distance. Just go out for an easy :30-:40 minutes.
I used to get stuck at the same distance all the time. Seems I wired my brain to stop my body at a particular spot on my route. One day I took a different route, and did over 3 miles without caving. So much of this is mental.
Enjoy your journey! ;)
On no account brood over your wrongdoing.
Rolling in the muck is not the best way of getting clean.
~ Aldous Huxley
~~I shed 56.8 lbs in 2008, and 20.6 in 2009!!! Happily maintaining!!!~~
My ticker represents my Maintenance range!!!
(Reset July10, 2009)
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