Running/jogging is definetly more challenging, and I love it... There is no way I could run 1/2 mile the first time out, and I biked, walked, did aerobics, etc... You definitely need to start gradually 1:1 (run:walk) within a couple of weeks you'll be up there with the rest of them...
Liz -- I don't like to hear my breathing either!! It makes me feel like I'm out of breath or something, I put the music up very loud, the people passing me though must think I'm about ready to die
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