Sneakers and sweatpants have always gone together, and sneaker culture has aided in the revival of the sweatpant in men's style. Although shirt choice can transform a pair of sweats into something more put together, the footwear choice can do that, too.
Now, that doesn't mean that someone has to wear a pair of hardbottom shoes to sport a pair of sweats at work, but a simple pair of Common Projects Achilles or an Air Max 1, or any other retro runner with clean lines, might be a more suitable look than throwing on a pair of extra-high basketball sneakers from the '90s. You're at work after all, not Sneakercon. Plus, runners and sweats just look cooler.