Training & Nutrition - Fitness and Calorie Burning

Where I live it's fairly hilly, though until recently I lived in a town where it wasn't. As time has gone by, the hills here have gotten much easier to climb. On my daily commute (~3 miles each way), I can now sprint up even the biggest hills, whereas at first it was a major workout just pedaling to stay upright. It seems obvious that I'm becoming more fit and in tune with my environment. I'm wondering what this means in terms of calorie burning? As I get in better shape, does it take the same number of calories for me to climb the same hill, or is my increased fitness actually causing greater efficiency and therefore a reduction in the number of calories required to climb?

I wouldn't think it would cause a reduction in calories burned. But it might mean less perspiration, less gasping for air, less pain in the leg muscles--that sort of thing.

I wouldn't think it would cause a reduction in calories burned. But it might mean less perspiration, less gasping for air, less pain in the leg muscles--that sort of thing.

That's kind of what I was thinking - except the "less perspiration" part (it being summer in Georgia, after all).

The laws of physics are very strict. To climb a hil from point A to point B, it takes the same amount of energy (calories) regardless of how fast you are going. Now if you do it faster, your body may be producing more Work, but that's a differant equation based on efficiency.
So, If you burned 300 calories to go to work at 12mph, you are also burning 300 calories to go to work on the same route going 15mph, because even though you are going faster you are doing it in less time. This is of course, if all other variables are the same, such as total bike and body weight, temperature, wind speed and direction, etc.

I am very glad to hear this! I am also getting better at hills, and find my overall heart rate lowering, which was beginning to worry me in terms of calories, because I still have a good 10lbs to lose!

The laws of physics are very strict. To climb a hil from point A to point B, it takes the same amount of energy (calories) regardless of how fast you are going. Now if you do it faster, your body may be producing more Work, but that's a differant equation based on efficiency.
So, If you burned 300 calories to go to work at 12mph, you are also burning 300 calories to go to work on the same route going 15mph, because even though you are going faster you are doing it in less time. This is of course, if all other variables are the same, such as total bike and body weight, temperature, wind speed and direction, etc.

isn't this all true only in a frictionless environment?

isn't this all true only in a frictionless environment?

sorry, not frictionless...never mind what i said---i was thinking of something else in my delirious state of mind.

you're assuming the same path, so yes, what you said is true...i think.

The laws of physics are very strict. To climb a hil from point A to point B, it takes the same amount of energy (calories) regardless of how fast you are going. Now if you do it faster, your body may be producing more Work, but that's a differant equation based on efficiency.
So, If you burned 300 calories to go to work at 12mph, you are also burning 300 calories to go to work on the same route going 15mph, because even though you are going faster you are doing it in less time. This is of course, if all other variables are the same, such as total bike and body weight, temperature, wind speed and direction, etc.

No. It takes the same amount of work, but not the same calories. A fitter cyclist can do the same work using less oxygen and burning fewer calories.

Let's say two cyclists are the same weight and age and have identical bikes, but are of different fit. If they ride the same hill, the fitter cyclist will do it burning fewer calories- and at a lower avg. heart rate. It is no different than having a more fuel efficient car- they can do the same amount of actual work, but they use different amounts of energy.

You might want to rethink your laws of physics.

Also, the faster you climb a hill, the more energy (and calories) it takes. If you don't believe me, strap on a HRM and get back to us.

Your theories are a bit wet...

I think it may be a number of things, your body is in better shape, if you lose a little weight, but maintain the same speed/distance, the formulas may show a lower calorie burn.

According to my calorie burn program that I use, I burn less calories now at 220 pounds riding for an hour at 16mph, than I did when I weighed 240 pounds. The main difference is now, I can ride for a longer period of time, I don't feel afraid of hills, I'm more aggressive on them. To me it just means I'm developing a more effective calorie burning machine.

Oh that's what I was afraid of. It's so unfair, the harder you work and the fitter you get, the more you are punished by burning fewer calories. I guess I'm going to have to push myself up those hills until I practically get a heart attack to get this weight off! :(

I think it may be a number of things, your body is in better shape, if you lose a little weight, but maintain the same speed/distance, the formulas may show a lower calorie burn.

According to my calorie burn program that I use, I burn less calories now at 220 pounds riding for an hour at 16mph, than I did when I weighed 240 pounds. The main difference is now, I can ride for a longer period of time, I don't feel afraid of hills, I'm more aggressive on them. To me it just means I'm developing a more effective calorie burning machine.

Agreed, I'm working on a program from my Dr and he gave a sheet with the formulas (if anyone is interested in details let me know) Basically as you lose weight your basal metabolic need (how many calories you burn just being alive) drops, and that is the greatest amount of calories you burn in a day. So the more weight you lose the fewer calories you burn RESTING, you can overcome the dropoff to a degree by increasing time/intensity of the workout, but only to a point.

Just one other thing to throw into the mix is that lean body mass tends to correspond with a higher BMR (basal metabolic rate), therefore comparing someone weighing 200 lbs that is flabby vs. fit, the fit person burns more energy at rest while not working out resulting in an increase in calories burned throughout the day. Keep in mind that working out is a great way to burn calories, but truthfully is only a drop in the bucket when compared to the amount of energy your body burns on a daily basis just to keep itself running.

Just one other thing to throw into the mix is that lean body mass tends to correspond with a higher BMR (basal metabolic rate), therefore comparing someone weighing 200 lbs that is flabby vs. fit, the fit person burns more energy at rest while not working out resulting in an increase in calories burned throughout the day. Keep in mind that working out is a great way to burn calories, but truthfully is only a drop in the bucket when compared to the amount of energy your body burns on a daily basis just to keep itself running.

Depends on how much you ride. Even if I halve what my HRM says for my calories burned, I'm still burning around 500 calories per hour and I ride at least an hour every day. I don't consider 20% (remember that's using my 50% conservative estimation) of my daily caloric consumption a drop in the bucket.