If you find the right pair of sweatpants, there's almost nothing you can't do in them -- especially these days. Adidas joggers are comfy as heck, sturdy, great for exercising and they're still kind of cool. Like, you could probably pull them off at brunch this weekend, if you were going to such a thing. The popular joggers are currently on sale on Woot, down to $26 for the men's sweats and $25 for the ladies' trainers. Both also ship for free if you're an Amazon Prime member.
I own a pair of these myself and must admit I've only rarely taken them off in the past couple of years. They've held together beautifully and seem to get more comfortable with each passing lounge-filled day.
The men's fleece joggers with tapered leg are available in four colors (black, white, green and navy) and six sizes from small all the way up to 3XL. The women's high-waist trainers are available in black and navy and range in size from XS up to 2XL.