I believe most people know that regular exercise will improve their mood. As a personal trainer, this is something I strongly believe! However, I also believe that getting outside and experiencing nature can also create many of these positive effects.
A good example of this is related to my son, Antonio. When he was about 6 months old, I started jogging and rollerblading with him (in a stroller jogger) on the American River Bike Trail in the evening after work. Sometimes I simply would not feel like doing it. After all, I had to pack up the stroller, get water for him and me, then drive the short drive to the bike trail. However, after I got used to the routine, it was no big deal. In fact, I found that if I did not take him for our nightly run, not only would I be in a bad mood, but so would he! After missing a few nights, then going out again, then missing a few again, I made the connection. When we did not go out, he was cranky and upset most of the night and would not go to bed easily. On the nights when we exercised he had a better overall mood for the evening and then went to sleep more easily. Of course, Antonio's mood could have been responding to my good mood, having had my exercise. Whatever the case, I truly believe that exercising outdoors is great for a parent and child's emotional and physical well-being.
To read further about the connection between moods and exercise, read this link to a recent NY Times article about how exercise boosts mood.