You don't mention it, but you HAVE to drink a lot of water. Especially if you are moving into higher percentages of proteins, the liver and kidneys need some help to flush that allout of you.
I'm almost the exact as you, except I'm 44. My 30 minute workout was running the track while my son was at swimming practice. I'd vary it between just staight runs, sometimes throwing stairs in there, and often doing (12-15) pushups every other lap.