The More You Do The More You Get Done (opens in new tab)

I usually do pull-ups, crunches on the pull-up bar, and lift weights (in the morning). I don't do cardio in the morning. The boost of energy I feel isn't apparent immediately after the workout (after all, you should have worn yourself out). The energy I feel might be from testosterone or perhaps it's just the feeling of being relaxed with your whole body kind of sore (in the good way).

For me I usually feel tired and crappy when I start going to the gym after a long break. I find that it is only after I exercise for a few weeks in a row that I start feeling good after a workout.

So my humble advice is to stick with your exercise routine for a while and see how that goes. good luck!

Edit: Corrected typo

It seems to work for women, too, for what it's worth.