I think that maybe a better idea would be to have a challenge for INCHES lost , not pounds. Because this gets us fixated on the number rather than our APPEARANCE, which is what really matters most. If your scale isn't moving OR it's moving in the undesired direction, that doesnt always mean you're getting FATTER. It could mean you're losing FAT and building MUSCLE. So a more accurate way to measure "weight loss" is not by the scale, but rather by INCHES LOST.