You were probably running faster outside. The breeze from running outdoors can cool you down and evaporate the sweat faster than when you are running on a treadmill. That makes it feel like you aren't running as hard, so you run faster to compensate, and end up running out of breath/energy faster outdoors due to the higher speed. I'd definitely try mapping and timing your outdoor runs to find out how fast you were actually going. I find that running on a treadmill with a 2 to 3 degree incline and medium firmness corresponds pretty well to my street times. Couch to 5K is definitely doable on the treadmill. This year I'm planning on doing couch to 1/2 marathon primarily on the treadmill.

You can definetely do a C25k on the treadmill.

You need to run a little faster than your goal on the street and run at a 1% grade.

I also try to run one day a week outside so my body will adjust to running outside.

Art

http://fitatfifty-art.blogspot.com/

lenzlaw wrote:

 

I trust you all realize that you're talking to someone who is probably not listening. He started this thread in August and has posted nothing since.

Funny thing is I hadn't posted in over a year, so by comparison this topic is relatively fresh.

MarkEichenlaub wrote:

 

Which half marathon are you shooting for?

Something in the Minneapolis, MN area in June or July. There are at least three candidates I'm interested in, but none I've committed to yet. It will be a "check the box" half marathon. It will be my first, and I want to get one in fairly early this year in case I get sidelined by injury later in the summer. If I run another half marathon in the fall I'll go for more speed instead of just survival.