I use to jig school to go to gym was a pro BMX er before I have always been busy, if you want to stay lean you need to do as much different types of training as you can really, and walk everywhere too, and when you my age you have to double that but I am only 10 percent bodyfat, 1.6 cholestrol, and in no danger place for my age so can carry on like a teenager.
I think they found that they were wrong on metabolic rates and that the highest were people who eat the most (makes sense); the obese, and healthy individuals had lower rates, their foods were also better (complex carbs) and didnt cause constant insulin spikes either, that alone drives fat into storage.
Plyometric training is pretty much jumping and the insanity I do is pretty much jumping for 3/4 an hour.