Because exercise can make you feel better, even if it seems counterintuitive cause you feel like you don't have the energy. Because if you set a little goal of an amount of exercise you want to get, and follow through it can be good for physical as well as mental health.
I do struggle with depression a bit, or actually quite a bit as I have reoccurring severe depression. but it does actually feel nice to go out and get moving around a bit, even if it is just for a short walk. And there is a little river near the trail by my apartment, so it is always possible to see ducks and canada geese but sometimes there are herons and pelicans to.
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Eat the rich, feed the poor. No not literally idiot, cannibalism is gross.