A lot can be said for the power of fresh air and sunshine. To start, the fresh air can help clear your mind and if you breathe purposefully (in through your nose, out through your mouth) you may even expel some of the toxins in your lungs.
Also, even a few minutes of sunshine each day, can provide your body with Vitamin D. A Vitamin D deficiency can lead to fatigue, bone, back and muscle pain, hair loss, and even depression. Remember though, not to get too much sunshine – avoid burning!