Found another inspirational Big Dudettes link (and it bumps up the thread):

http://www.bfpd.com/pages/FatGrannyonaPurpleSchwinn
Just a snippet:

"A man I passed the other day summarized it in a way I never could have... As I huffed and puffed up a hill on the tandem... my four-year-old in the trailer being pulled behind and my 9-year-old on the seat behind me barely pedaling... my face beet red and my hair drenched with sweat, I noticed a man who had been washing his SUV stopped to stare at us. I felt I needed to explain and so I shouted, "I'm too fat for this!" To which he responded, in the most gentle, reassuring voice, "You're doing just fine, just look at those smiles behind you.""

... first time I read it, I thought it said, "You're doing just fine, just look at those miles behind you..." and that would work too!