One of the symptoms of major depression is psychomotor retardation which causes people great difficulty in performing even simple tasks, like brushing one's teeth, doing the laundry, or showering. Advocating exercise as a cure for a disorder marked by the inability to exercise seems short sighted.
"I can't get out of bed"
"You should exercise"
Ugh...
"I can't get out of bed" "You should exercise" Ugh...