Here's where you can find the study: http://strengtheory.com/the-science-of-steroids/
"Yes, you’re reading that chart correctly. The group that took a placebo and worked out only gained
slightly more strength than the group that took testosterone and sat on the couch for 10 weeks. The group that took testosterone without exercise gained just as much, if not more, muscle mass than the people taking a placebo and actually working out."
...
"So for people who say, “oh, steroids don’t make you bigger and stronger. They just let you work harder,” I’m sad to inform you that such a statement is
patently false. They may help with recovery and let you work harder, but I guarantee you that you could stick with the exact training routine you have now, start taking steroids, and gain more size and strength from it – no extra work required. And an untrained person might (would probably) gain more muscle from just taking steroids than they would if they actually worked out."