When I saw this thread I was thinking - what take drugs and exercise? I guess I am still sick in the head.
I think a little movement is great for everyone regardless. This was especially true for me coming off opiates / heroin. I was unable to get out of bed or off the couch during many of my kicks until about day 4. Once I was able to I would push myself to get the blood and brain flowing again. A healthy sweat versus flop sweats from detox.
Glad to put that behind me. 4 and a half years since I had to do that and don't miss it one bit!!!