Originally Posted by
wphamilton
Try this: You decide to do 200 watts on two rides of ten miles. One ride it flat, the other is 5% up for five miles and 5% down for five miles
Plug the numbers into the calculator, keeping the power at 200 watts.
The flat ride burned 348 calories.
The hill ride burned 375 calories climbing, and then 106 calories descending, for 481 total.
But that's kind of a cheat since that the hill ride took longer. Make the time the same and the calories will turn out the same. Yet the calories per mile will be 48 for the hill ride, and 35 for the flat ride!
I'm going to stop geeking out here before someone complains, but playing with the power calculator is always fun.
...a constant 200 watts is the key -- the 200 watts
per minute (12,000 Joules -- about 2.857
food calories) in your examples will be the same by definition. Over a given amount of time the energy used will be the same. And, the rider in the examples above cannot do 20 mph on flat ground without expending more energy -- i.e., >200 watts (~215 watts). More speed takes more power... and, will use up more calories.