Winter is a time for long walks, wrapped up well and with good walking shoes/trainers, with frosts sparkling on the ground, berries red upon the bushes and trees, cold but you soon warm up as you pick up the pace, as long as rain isn't forecast you are good to go, if you are able to walk that is, however, even if your mobility is limited, try a short stroll. It gets rid of all the cobwebs, opens your eyes to your surroundings, if it is built up walk around the streets and have a nosey at people's gardens etc., trot past the shops and maybe catch a take away coffee or hot chocolate, if you are near a park or the countryside take in the beauty of nature in the winter, a rugged stripped back landscape, stark tree limbs revealing the emergence of mistletoe, evergreens keeping hope of more fertile months alive.
Enjoy it. Life is too short.