No matter how many cleansers and face masks I've tried, my sensitive, breakout-prone skin ALWAYS benefits from getting some fresh air- especially when the weather is brisk.
I noticed that my skin appears brighter after I spend some time outside, in a way that is different from exercising inside. This may not be the case for everyone, but personally, I feel that any blemishes on my skin clear up more quickly when I get fresh air consistently.
I recommend spending as much time outside as your lifestyle allows- this could mean taking a few short walks while running errands, a 30-60 minute walk during lunch, or a bike ride. Personally, I choose to walk to work every day, walk when I run errands, jog outdoors when the weather is nice, and try to eat lunch at my desk only when I really need to.
I also recommend not allowing the winter cold to scare you! Unless the weather conditions are dangerous, stepping out into the cold air is worthwhile based on my experience. It seems that blemishes refuse to come out to face the cold!
Of course, fresh air is not the only component of a healthy skincare routine, but in my opinion, it's an essential one.