I was out for a walk the other day, and about halfway through I realized I was completely lost in thought. I snapped out of it, took some deep breaths, looked around at the trees and sky, and felt the sun on my skin. The contrast was so marked, it really made me appreciate the difference between just being outside, and being outside with awareness. There is a healing power in nature and it is much greater if we consciously tune in to it.
One simple way to tune in is to become aware of the feeling of your feet as you walk, or run, or even sit. Feel the sensations of your feet as they press into the ground. The body is always in the present moment, so becoming aware of sensations in the body is an easy way to come out of thoughts and into the present.
Taking deep breaths is also very healing. Completely empty out the lungs, then take a deep, slow, cleansing breath. Repeat that several times. It is cleansing for all of the cells of the body, as well as for your energy system. It has the added benefit of being very relaxing. It can bring us out of the fight or flight mode that many of us are in so much of the time.
Finally, tune in to the energy of the trees, grass, plants, water, earth, and animals. All of these parts of nature have very alive energy and we can be revitalized by consciously tuning in and breathing in, these energies.
In winter it is especially important to make the effort to spend some time outside each day. It just doesn't happen as naturally as in warmer weather when the days are long. So, even if it's just a few minutes at your lunch break, step outside, feel your feet on the ground, take some deep breaths, and drink in the healing energy of the natural world.