[XXXNoahXXX]

I lifted for three years exclusively using free weights and had developed a few routines that I really liked and got great results from. Then I hurt my lower back, didn't work out for months, and when I got back to it, I couldn't do free weights any more. I switched to do machines only and was prepared for much diminished results, but i was actually very impressed. now i involve both in my workout and I think that is optimal (especially since im still worried about my back).

Not sure what this adds, but just wanted to say that if you use machines right and don't just go through the motions you can still get a very intense workout with great results.