When I have SAD hits around the end of January/February exercise, a healthy diet and my sunlamp are often some of the only things keeping me from an episode of severe depression. I feel my most calm and at peace when exercising (meaning not feeling apathetic, listless or sad). It's usually a lifeline for me in those months. I know it's good for me so I force myself. Although with SAD (at least for me) unlike typical depression, I don't think really negatively about myself (no negative self talk), it's more zero energy/fatigue, feeling very apathetic or sad, struggle to experience happy emotions, inability to focus, and things don't bring enjoyment.