A few weeks ago I had a metabolic analysis at the gym where I work out.
They hooked up an oxygen sensor mask and heart rate monitor and had me ride a bike for 30 minutes at increasing resistance rates.
The idea is to try to determine at what heart rate your body crosses over into non-aerobic exercise, and you are no longer burning fat, but rather stored glycogen.
They pretty much told me I was exercising too hard and put me on a program of 4 days per week of exercise (instead of 5). Each day is different and pegged to a different combination of heart rates. One day is ure interval training, alternating between 120 HR and 160 HR. Other days are 20 minutes at 120, 20 at 130 and 20 at 140.
The theory is that you can increase the heart rate at which you are still burning fat. I go back in August for the same test and we will see if I have moved my numbers.
