Here in North America it is winter. With winter comes cold weather, less sunshine, and increased stress levels. While upping your intake of Vitamin D is one way to help offset the lack of sunshine, it isn’t enough for you to reduce your stress.
Going for a walk may not be an option in the cold weather, so why not go for a walk indoors? If there is a mall close to where you work, you could walk around for 10 minutes during lunch, do some window shopping, and get away from your desk and your phone for a while.
Relieving stress is key to helping you remain productive. When you are productive you are efficient. When you are efficient you are maximizing your time wisely. It is really that simple. Would you rather spend an hour trying to plod through one task or 30 minutes of walking around a mall and then 30 minutes finishing that same task?
I know what my choice would be.