Any Curlers on this Site?

Alright so I don't expect a huge response as curling isn't exactly the NFL, but I'm trying to find the calories burned while curling and I found a website that actually has curling as an activity but the calculator comes up at 650 calories burned for 100 minutes. That to me seemed a lot. (Their calculations for other things seemed spot on though). I threw a couple hundred calories into MFP just to add something, wanting to be fair to myself!
Anyone have some thoughts on the energy spent curling? I don't want to wear my HRM for two hours curling, but it's looking like I might have to.