High Heart rate at a low work rate.

When you are doing cardio your heart rate increase as a result of you working your muscles. Therefore to provide energy to your muscles your body increase you metabolism. My question is what happen if you elevate your heart rate without really increasing the work rate. The reason I ask is out of curiousity. If the weather is good I spend most my weekends skydiving and I was just thinking that drives my heart rate way above normal for a few minutes at a time! But since gravity is doing most of the work the actual muscle/work effort seems pre low incomparison to running or swimming. Anybody have any ideas on what way you metabolism works in this case?

I never though that it would make me any fitter, "if only!". The only thin skydivers are the ones who work at skydiving and spend all day jumping and running around and are generally too busy to eat, which is why they're thin. I was more curious really how the body reacts really.
There has been a number of post of origin test results, plotting the % fat and carb being used at increasing heart rates. I was curious as to how this would differ if the stimulous for the heart rate was adrenaline induce rather than by cadiovascular excerise.

well you body has a limited adrenline production rate so if you use it up before you start lifting then there shouldn't be any to interfer with lifting. Even if there are meds to halt the production I really wouldn't recommend using them. I would suspect that it also helps you lift big and its anxeity thats causing the problem