Winter is here.

Short days, and dark mornings mean less sunlight. Cold temps mean getting outdoors is a chore, requiring layers, coverage, trying to stay warm. Roads are littered with ice, cinders, and compromised shoulders. Rivers and lakes are not an option. Much of our beautiful hikes and treks are stifled in snow.

In the winter it is not uncommon to feel down, to ruminate on the cold and dark, and to feel sad that most of our enjoyable activities need to wait until next year. One in 15 people suffer from the "winter blues," also known as SAD (seasonal affective disorder). SAD is a depressive condition linked to the time of year. Symptoms of SAD include: irritability, fatigue, sadness, trouble sleeping, decreased concentration, low enthusiasm, and guilty thoughts. If this sounds familiar, there are some viable options for treatment aside from pharmaceutical antidepressants.

First, part of our environment that's tied to mood is the amount of sunlight we see daily. There is a benefit to seeing more sunlight. Get outside and try to get in 30 minutes of sunshine when the sun is out. Also, there are devices which emit a very bright light that mimics sunlight. These also have been effective. Light therapy lights with 10,000 lux (a measure of light power) with an exposure of 20-30 minutes are recommended. They can be found online and are not too expensive.

The next step in treating the winter blues is to ensure adequate exercise. The recommendations are 40 to 60 minutes at 50 to 85 percent of heart rate max, three times a week. This intensity can better be described as moderate with a difficulty of 6-7 out of 10. This provides a good stimulus to the aerobic system. Studies have reported that with exercise more than 80 percent of those feeling depression showed improvement, while with drugs alone only 60 percent showed improvement. Exercise's other benefits of reduced blood pressure, increased positive brain chemistry, and better sleep also coincide with a better mood.

BDNF (brain derived neurotrophic factor) is a chemical which strengthens and builds brain cells; when exercising there is a rush of these chemicals, particularly to the hippocampus, the area of the brain which is seen as compromised in depressed individuals. The other master chemical is serotonin. This is a "feel-good" chemical which is also known to be lacking under depression, and many of the drugs prescribed are working to promote serotonin. This can also be achieved with exercise.

Other good advice is to eat healthfully. A clean diet contains micronutrients and energy that the body can use to ward off the depressed inertia of winter. It also can be noted that the psychological momentum of one healthy behavior leads to another which may help promote an exercise or activity habit.

If your depression is severe, ongoing and hard to shake, seek medical attention.

For many of us, it could be argued that exercise ought to be treated like medicine. However, it's hard for doctors and psychiatrists to prescribe. They have no way of knowing whether their patients are compliant, and are likely not trained to describe and administer an exercise program. Still, knowing that exercise is effective is a step in the right direction and it ought to be promoted

more.

This season, fight off the winter blues - and use exercise as the way to succeed.