Congratulations, Playalot! I figured you would ace this challenge.
My strategy was to keep my Sim very energized in order to overcome any negative moodlets from working out. He mostly worked out at the gym so he could be mentored. I divided his time between the weight machine and the treadmill since he could get fun (from the TV) and social (by chatting) while on the treadmill. Since he was almost always very energized, he slept very little. Every day when he got home from work, he would eat and start his daily task (study opponents) on the tv, thus gaining fun. He would then switch to the computer to finish the task, since that is faster.
I also bought a tub and he used the muscle relaxing soak + incense every day to get the 12-hr energized moodlet, which kept him energized for his entire work shift. In addition, he drank the energy shake, researched workout tips, and viewed his career reward painting. He went to work with at least +10 energized every day. He never got married. Instead, I bought a massage table and he hired a masseuse every day. He got the deep tissue massage, which gives a 24-hr +1 happy moodlet. He went to the spa once, but I felt that took too much time. I only asked for bonus once, for his final promotion. I'm not much of a gambler and I really held my breath on that one! I never even thought of hacking his work performance, but he still managed to get a promotion pretty much every two days. I can't remember what day he completed the bodybuilder aspiration (need to keep better records!), but it was early on. For the last week or so, he went out dancing quite a bit since all we were doing was waiting for promotions.
I also did not join the career until he got the connections reward.
