Well, I gotta tell you something you may not like. In fact, I just reread the beginning of a text book I had to study for my personal training certification some years ago and it cautioned that trainers would at times have to tell people things they did not want to hear. The example in the book was having to tell someone they had to give up the hot fudge sundae to lose weight. My example is having to tell you, my readers, that if you really want to have excess calorie burn, or increased metabolism, for hours after your workout you have to work your ASS off.
I was sent a link to someone else's blog by a personal trainer, dancer, runner, friend that I respect very much. The blog post was incredibly technical and I am still scratching my head over it. Jennifer thought I would be interested, and I was, but oh boy, I was hard pressed to follow along.
Firstly, it seems that the energy burn we long for has a lot to do with the oxygen consumption we do after our exercise. In fact, this is called EPOC to stand for excess post exercise oxygen consumption. EPOC is only one measure of physiological change we cause during exercise that contributes to calorie burn. I know you have heard of lactic acid threshold and maximum heart rate, those too are involved. Along with this is the individual characteristic of YOU and also the activity you are doing and how long and hard you are doing it.
I could break down the blog post that I read but you know, the bottom line is really what matters.
If you want to increase your metabolism or calorie burn for any length of time after your workout then you need to push yourself beyond your comfort zone. You should run, swim, cycle, dance, step, etc. , so hard that you lose your breath. You should lift weights so that the muscle in question burns and quivers and no further reps are possible. You have to lift HEAVY or do full body resistance like push ups and pull ups.
Exercise at less intense levels and you will absolutely benefit and burn calories. If you are going to tell yourself that three hours later you are still burning more calories than most people, then you really have to work for it.
Another thing I read in my book today - the people I teach or coach have more control over their health outcomes then I do. If you want this, then go out and get it.