If your workout lasts more than 50 mins. you are over training or if you last more than 50 mins. you are not training hard enough. IMO Good or bad Genetics does not have anything to do with how long you should work out. All of our muscles are made up of the same thing. Genetics will be the deciding factor on how far you can take your body. The key in training is intensity. If a person is working out with intensity there is not way that workout can last 2 hours.

Once again, IMO, one should do no more than 2 exercises per body part, and no more than 3 to 4 sets per exercise.

There are times when I get to the gym I see a guy working chest. I do my whole workout in 50 minutes and the same guy is still doing chest while I walk out of the gym. That is crazy, and the thing is the guy looks the same day in and day out. He is killing his muscles just like a marathon runner kills his and he see no progress. My philosophy is get to the gym, work your ass off for 50 minutes and go home to let your body grow. No more than 1 min rest in between sets, slow and controled reps, 2 to 3 seconds on the positive and negative. 3 to 4 sets per exercise and 2 exercises per body part.

I know there will be different opinions on this. I respect everyone's opinion and guys this is just my humble one. But, the more advanced you are the less time your workouts should take...Later....

PS. Bump to YAMAHA...good advise bro...