double tracking exercise?

I have the Garmin Vivofit, and that syncs with MFP for steps and everything, naturally. But I also use mapmyride to track my road cycling - and when I do this, I simultaneously use the vivofit to track my HR and calorie burn. When I sync everything back with MFP, it thinks I've burned twice as much as I did because it records the calories from both mapmyride and from the vivofit. Is there any way around this, or will I manually have to delete the duplicate workout every time?