The single-best exercise for my back was doing squats. Those, probably mixed with deadlifts, build up my back muscles and my posture corrected itself. (I was sl

The single-best exercise for my back was doing squats. Those, probably mixed with deadlifts, build up my back muscles and my posture corrected itself. (I was slouching a lot.) I just can't think of anything more effective than those two exercises. (Perhaps swimming, though.) I also recommend proper warmups. e.g. start with no or very little weight, and then keep adding until you reach your maximum, then do 3 sets at the maximum. I usually do 5 - 8 reps each set. As for time investment: 2 - 3 times a week (doesn't matter if I was tired or lazy, I knew I would feel fantastic at or after the gym), 60 - 90 minutes each time. (no time-wasting, breaks only as long as necessary.) As for 80/20: After doing the squats and the deadweights, I usually feel very motivated to keep doing other things. It's really switching the body into "workout"-mode. Check these two videos for proper form: http://www.youtube.com/watch?v=huVujjfzphI http://www.youtube.com/watch?v=huVujjfzphI , http://www.youtube.com/watch?v=0JYCvtNKWc8 http://www.youtube.com/watch?v=0JYCvtNKWc8