I thought I should reply to this. I am transitioning to morning training. I went for the first time on Tuesday and it was a lot better than I thought it would be. What I liked most was that I didn't have to go into work as soon as I got up. I looked forward to training and having the hour or so to myself to do something for me before starting the day. I got a good nights sleep that night too - I believe that made a big contribution as well. As far as in the injuries go I suspect the cause was from three things: I was probably training too heavy on my assistance lifts, had a bad mindset from being exhausted at the end of the day (just wanted to get in and get out and didn't enjoy the process at all), and was sleep deprived regularly.
My training motivation for a long time was to get stronger and there are a few reasons to that. Aside from being healthy I used to get picked on when I was in school. Don't ask me why, kids are dumb. However, even though I got picked on rarely would anyone try to fight me because I played football and I was pretty strong. I still got shit as an adult and my strength was always a good insurance policy. Im probably about average strength amongst people at T-Nation, but in the "real world" I'm probably top 20%. The same is true for my gym which has a lot of really strong and cool people. As a funny story, one summer I had this girlfriend that cheated on me. I was so mad that I devoted the entire summer to squatting just so I could beat the shit out of the guy she was with. In about 8 weeks I went from 225 for reps to 305 for reps. I never got to kick his ass though, but she came running back to me at the end of the summer haha - this was in 2011.
Now as a young adult, having a broad and big build does make a difference. I am sure some of you have noticed with your own experience. Bouncers are nicer to me a clubs, people pick less fights with me at bars, guys at work are more friendly to me, women flirt with me more, people want to talk about exercise, I feel more "in charge" when talking to strangers, I feel like in general people listen to me more. The notion that looks don't matter is bullshit.
As far as taking supplements like stimulants, I am against that for personal reasons. Besides my own experience, I know people close to me who took drugs like those and it ruined their mind and body. Id rather be tired and just deal with it than take a drug and accumulate damage to my body in a few years. There is no free lunch. You wont see it in your 20s, but when you are beaten up in your 40s, 50s, and 60s, or crash hard when you don't have whatever you use regularly, you know something is wrong. It isn't worth it, if my body is too damn tired Ill make time for a nap or meditation.