So, we've rounded up the best options, including ultra-warm picks from Carhartt, Wrangler, and a flannel-lined jean ... the cuffs rests neatly over your work boots and the pockets can store ...

Some proof: instead of a hoodie, throw on a flannel when heading to the gym; wear an open flannel with a white tee and jeans shorts for ... and a pair of statement boots. In warmer weather ...