If you cant attend life drawing sessions. This is the best thing for you
Let me show you something I recently found : Croquis Cafe!
You get to see models of different colors and shapes in a life drawing setting. They move and breath while posing (breathing like in real life :O) ambient music is playing in the background and you have 1, 2 and 5 minute sessions. I find it very helpful , you should try it.