Lollybell: Congrats on your decision to do this!
My wife Silver is the cycling coach for the local Y's tri-training program. I'll tell you that the most enjoyable folks in that group are the ones in their 50's and 60's who are doing this for the first time!
Age isn't the limitation and you'll find that you get all the benefits you seek in weight loss, energy gain, and self confidence!
PM Silver if you want some direct feedback from her. We're mid 40's and she just did her first tri a couple years ago...
If you don't grow where you're planted, you'll never BLOOM - Will Rogers