There are a few reasons you might not sweat when you work out. One is all scientific and medical in nature -- something about cells in your sweat glands. Another: You might not be working hard enough. Or maybe it has something to do with coffee, dehydration or the air around you. "Love and Blueberries" helps you figure it all out.

And if you're sweating a lot, well, that might not be a bad thing. Here, Fitz weighs in on sweaty pits.