I can't believe your boss said that. First of all, he's your boss, not your doctor, and unless your doctor tells you you're 'too heavy' (which you're not) to run, then so be it. The boss probably keeps stick insects at home as a hobby, so whenever he sees something that is not capable of fitting through a keyhole, he thinks of it as 'heavy'.
Blah! Run, Kim, run like the wind! [/Forrest Gump reference]
What an evil thing to say...you've shown us pictures of yourself and you're not fat at all.
I don't think it was evil so much as thoughtless - Corrie, remember when Clay Aiken said that Simon Cowell didn't have the "filter" that most people have, that helps you decide what should be said out loud and what shouldn't? I think that statement applies to my boss, too. I'm sure he didn't mean to hurt my feelings, and he probably forgot that he said it five minutes later. 
Unfortunately, though, I have the memory of an elephant - albeit an elephant with self-esteem problems who remembers bad things more often than good.
Yes, I can see him saying that! He does have a way at jabbing whatever insecurities you have. Oh, how I DON'T miss that! But it does motivate you; maybe its his secret motive? I can't say what goes on in that head of his!
I can't believe your boss said that, filter or no filter. At least it's given you a motivational tool.
I still vividly remember when my doctor looked my body height and weight up on the chart and said I feel in the morbidly obese category. That memory motivated me through some tough runs. I just had a check up with the same doctor and he was pretty surprised. He said I was the picture of health.
If you really want to get him back, it is never to late to challenge him to the run! I've never had anyone take me up on the challenge, not an elite runner, not very fast but I'll run til after they quit! I like an old saying " Don't take yourself too seriously, noone else does!" Just turn that one around on things the Boss says! Run Good!
Commenting by HaloScan
