Depression and exercise are somewhat related. More moderate forms of depression can be alleviated with exercise, although more severe forms of depression would probably need clinical treatment.
You might be able to get away with not having to take medication in these milder forms of depression, if you do regular exercise. This isn't a given, but it has worked for many people.
Even if you have a more severe form of depression and you have to take medication, it would probably be in your best interest to exercise anyway. Exercise can't hurt. I know you might be not be able to do any exercise because your days are so miserable and you don't want to get out of bed. But if you can manage to gather up some energy to do some regular exercise, it would be good for your body.
Walking would be the simplest to do. If you do anything, walking is your bigegst bang for your buck. Sometimes people tell me they know someone who has mental illness and often they say she or he "walks a lot".
Going for a jog or a bike ride would be the next level up. There's something about moving your body a good distance at a decent clip that really invigorates you. I know if you have depression, you may feel that nothing makes you feel any better, but I believe at some level, doing some exercise still has an effect on you, even if it feels like it doesn't.
Working out with weights is also another good form of exercise. Try the Convenient Workout I tout on this website, for example. It is easy to fit into your day. Or try hitting the gym. I know it may be hard, but maybe you could try. Commit to trying it at least once and see how it goes.
A trick I read about is going to a gym, parking in the parking lot, staying there for a bit and then leaving. If you have a hard time getting the motivation to go to the gym, this might work. Try doing this for so much time and maybe you'll get the courage to go into the gym one day.
One lady I read about, got a gym membership, went to the gym, stood on the treadmill and then left. She did this for awhile. Eventually one day she started to walk/run on the treadmill and was doing an actual workout. This was the trick she used to get her to the gym.
Depression and exercise are related in that sometimes if we don't do enough exercise, that could make us depressed in the first place. There are probably people in the world who are happy even though they aren't very active. However, I'm sure there are many of us who have become depressed because we've put exercise on the backburner.
Sedentary lives, coupled with stress and unhealthy diets have gotten the better of many people.
There is also the aspect of exercise as a natural way to deal with stress. Earlier in people's history, if you experienced stress, you reacted to it, for example, by running away from a tiger. Nowadays, we have to squelch our instinct to run. We can't just up and leave our job at a moment's notice. We can't hang up on a person on the phone. We can't run away from our desk.
So going for a run or working out lets us do what our bodies are really trying to do when we experience stress. But even though we may do the exercise sometime after the stressful incident has occurred, it can still pay off. By doing regular exercise, you can help lower your daily baseline stress levels. This could make the isolated stressful incidents not as stressful.
Exercise can give you confidence and get you back to enjoying life again, so those stressful incidents don't seem stressful at all. You may even begin to enjoy those stressful incidents! Imagine that!
One runner I read about said that when he runs, he feels like he is "accomplishing something".
Depression and exercise can be put together to give you your life back. Not only could you get your happiness back, but you could have a fitter body as well.