I have NEVER seen or heard anyone mocking someone at a race due to their weight. Not something I'd ever worry about if I were you. Good luck.

I have not been in a triathlon either (training for my first Sprint), but I understand your feelings. I tried on some bike shorts this weekend that made me feel really badly about my body. I had the same type of thoughts. BUT...I did remind myself that in the million races I have run, I have never heard one person say something negative about another athlete. I know a triathlon is not a race, but I think that in all sports, the participates respect one another and know how hard the others are working! I think it is awesome that you have given yourself this goal and will complete a tri. We all start somewhere. I'm at the very beginning!

I'm at big round guy also. My very first triathlon, I raced it on this wacky, almost beach cruiser styled trail bike. At one point I was really pumping hard, just going at it. And this shmuck in all his hard core badass biker outfit and bike gear stuff flew past me, turned, and smirked. That was 2007, and it was the one and only time I've ever seen somebody give some form of dressing down to another triathlete.

It just doesn't happen. Most triathletes are tickled pink to see newbies, or locals, or people who just don't look the hardcore part. There's something about watching the new guys, and remembering what you went through yourself, that keep the veterans smiling. It's so great when old veterans get to watch new guys experience the same joys they've been experiencing for years. Those few who don't see life that way? They're not gonna bother you, because you're no threat to them. They only care about the people who can keep them from winning a podium spot. So messing with you is a waste of their time.

So, here's what's gonna happen: You're gonna train as best as you know how. Then you're gonna show up at race day scared, frustrated, uncomfortable, a real fish out of water. Then you're gonna walk by tons of people chatting and laughing and talking tri smack about this new saddle or that old pair of shoes, or how (cool/silly) people in Vibrams look, etc etc. Eventually you'll figure out where you need to be with your gear, and start setting up your transition. It'll inevitably be next to or near somebody else who's relatively new to things, and the two of you will start talking, eventually trading stories about this weird training tip you heard, or that bit of gear that you weren't sure about getting, and you'll settle down.

Then the race will start, you'll be on your way, and an hour or so later as you're crossing the finish line, your life will have changed.

Happens all the time.

Enjoy your newbieness. You're only new once.

Just to add to this, at my tri club I am one of the chubbier ones (I have just joined, I'm preparing for my very first tri) but there are so many different body types even among the club members, including overweight.

I just finished reading The Slow Fat Triathlete by Jayne Williams - it made me feel so much better!

I read this book, too! I need to re-read it again because now I'm a lot closer to race day! Loved that book.