Why is it possible to burn more calories by having an increased heart rate while working out?

Calories burned. Having a higher heart rate during activity is usually due to increased intensity of activity. Increased activity intensity burns more calories for same time period.

Related Questions

What to do if heart rate v sweat which is a better measurement for calorie burn up?

Heart rate. Consider this: you exercise at 85% of your maximum predicted HR for 30 minutes and burn up X calories (depends on your age, weight, sex). Versus-you sit at your desk for 30 minutes in 85° temperature pouring off sweat, burning 0 (or very few) calories. Heart rate wins because it is more directly proportional to your muscular work. (at least, that's my opinion). But it's a GOOD question!! Read more...

Is the rate at which you burn calories dependent on how fast your heart beats, will medication that makes your heart rate increase burn more calories?

Not dependent on hr. not a bit no. For that matter diet pills that induce significant weight loss do not significantly raise metabolism. ( I try for 1000 calories out per day; studies showing m a y b e a tenth of that with drug induced metabolic effects are what I mean by NOT significant). but changing thoughts/ behaviors help. http://www.amazon.com/dp/0692496157/ Read more...

Does having an increased heart rate let you run faster?

No. Not sure i understand the question. Maximal predicted heart rate decreases naturally with age. Heart rate must increase to support increased oxygen demand. The amount of increase depends upon several factors. Your heart knows what to do! a high resting heart rate does not make anyone run any better. Read more...