Sorry if everyone has been over this stuff a million times...

I currently do some pretty fast walking, but I want to try jogging soon (treadmill). Do I need different shoes?

Does anyone use trail running shoes in the gym? Any reason not to?

Thanks everyone!

I'm a little confused about why you don't see getting a proper fit by a professional any time soon... shoe fit is really, really important and every shoe is made so differently and every size is so different, even from year to year! So until you are fit with a pair that works for you, all the advice is really just theoretical...
You can always go try them on, get fit by a pro, then write down the details and see if you can find the same shoe for less online. I do that with bras, as I can find the salon bra online for around $100 LESS...
Good luck-
Kira

You are right, of course. And as soon as I wrote that, I realized it was pretty dumb and edited it!

Sometimes I get "happy fingers", too!
I think that running shoes are specific for running, in terms of their composition and size.
Here is the "definitive guide" about shoe selection with respect to your questions -- just follow the link
http://www.runnersworld.com/article/...4615-0,00.html
It might help you decide about what shoe will fit your needs the best.
Also, check out the shoe thread at the top of this forum page -- it has gots tons of great info!
Kira

Thank you Kira! The link and the thread are extremely helpful.