Energy expended and duration of aerobic exercise

terence

I've just noticed something on the Exercise Tab that contradicts what I always believed about aerobic exercise.

The number of burned calories for 30 minutes of brisk walking is 163.
The number of calories burned for 60 minutes og brisk walking is 326 (exactly double for twice the time).

My understanding is that you burn more in a second 30-minute segment of a continuous 60-minute aerobic exercise.

Do I have it wrong, or is the calculation simplified on this site?

SHBoss1673

ahh, well that depends on a lot of factors, 1st I would classify aerobic workouts into different types before I made any kind of conclusions.

Technically, it's about heart rate and oxygen consumption, not about the type of aerobic exercise.
I generally classify aerobic exercises in 3 sections, light, moderate, and hard.
I would classify a brisk walk as light aerobics (heart rate in the 50 to 65% range), jogging as moderate aerobics (heart rate in the 65% to 80% range), and running at or above your pace level as hard aerobics (heart rate above 80%).

To answer your question you just need to know the heart rate, if your heart rate stays constant, the calorie burn will be constant. Plus, remember, MFP's exercise database is a wiki style database, which means users enter the calorie amounts. This means that your calories burned for an exercise can be far different from what someone else burns based on your statistics, the level at which you walk, and the environmental conditions you walk in. The best way to know how many calories you burn with any real accuracy is to get a decent Heart Rate Monitor, or to go to a metabolic testing facility and be tested, while being tested is the most accurate way, it's expensive, and a HRM is usually about 95 to 99% accurate if you use a good name brand model that tests their products out extensively.

terence

To answer your question you just need to know the heart rate, if your heart rate stays constant, the calorie burn will be constant. Plus, remember, MFP's exercise database is a wiki style database, which means users enter the calorie amounts. This means that your calories burned for an exercise can be far different from what someone else burns based on your statistics, the level at which you walk, and the environmental conditions you walk in.

That makes perfect sense. Thanks Boss!

arewethereyet

Yeah but Steve........when you enter walking 4.0 for 30 mins, and I enter the same thing we get different numbers. There has to be some sort of formula in the background

edit to add:

Walking, 3.5 mph, brisk pace 30 minutes 117 calories

arewethereyet

:glasses:

SHBoss1673

Yeah but Steve........when you enter walking 4.0 for 30 mins, and I enter the same thing we get different numbers. There has to be some sort of formula in the background

edit to add:

Walking, 3.5 mph, brisk pace 30 minutes 117 calories

yep, it takes into account your weight and height, and age and sex. But those are peripheral factors, it's still using a single multiplier, which isn't the same for everyone so while you may get close, it's an estimate based on the person who created the exercise.

arewethereyet

Yeah but Steve........when you enter walking 4.0 for 30 mins, and I enter the same thing we get different numbers. There has to be some sort of formula in the background

edit to add:

Walking, 3.5 mph, brisk pace 30 minutes 117 calories

yep, it takes into account your weight and height, and age and sex. But those are peripheral factors, it's still using a single multiplier, which isn't the same for everyone so while you may get close, it's an estimate based on the person who created the exercise.

so Mike has no set exercise like the food log?

SHBoss1673

Yeah but Steve........when you enter walking 4.0 for 30 mins, and I enter the same thing we get different numbers. There has to be some sort of formula in the background

edit to add:

Walking, 3.5 mph, brisk pace 30 minutes 117 calories

yep, it takes into account your weight and height, and age and sex. But those are peripheral factors, it's still using a single multiplier, which isn't the same for everyone so while you may get close, it's an estimate based on the person who created the exercise.

so Mike has no set exercise like the food log?

right (I think, I can't be sure as I can't see his code) but based on how the site reacts, that's my belief. You may want to PM him to ask, I'd be curious.

arewethereyet

Yeah but Steve........when you enter walking 4.0 for 30 mins, and I enter the same thing we get different numbers. There has to be some sort of formula in the background

edit to add:

Walking, 3.5 mph, brisk pace 30 minutes 117 calories

yep, it takes into account your weight and height, and age and sex. But those are peripheral factors, it's still using a single multiplier, which isn't the same for everyone so while you may get close, it's an estimate based on the person who created the exercise.

so Mike has no set exercise like the food log?

right (I think, I can't be sure as I can't see his code) but based on how the site reacts, that's my belief. You may want to PM him to ask, I'd be curious.

I just entered Jeannie Bicycle kicks to my log and it is not in the main log. I do believe there is some sort a base for all of it. Otherwise you would also get 117 for your cals burned, right?

I know it is very very close to the HRM cals burned almost every time

SHBoss1673

Yeah but Steve........when you enter walking 4.0 for 30 mins, and I enter the same thing we get different numbers. There has to be some sort of formula in the background

edit to add:

Walking, 3.5 mph, brisk pace 30 minutes 117 calories

yep, it takes into account your weight and height, and age and sex. But those are peripheral factors, it's still using a single multiplier, which isn't the same for everyone so while you may get close, it's an estimate based on the person who created the exercise.

so Mike has no set exercise like the food log?

right (I think, I can't be sure as I can't see his code) but based on how the site reacts, that's my belief. You may want to PM him to ask, I'd be curious.

I just entered Jeannie Bicycle kicks to my log and it is not in the main log. I do believe there is some sort a base for all of it. Otherwise you would also get 117 for your cals burned, right?

I know it is very very close to the HRM cals burned almost every time

no no I think what happens is it takes your calories burned, factors in all the numbers, then uses that percentage for anyone who uses this exercise at this level. And that becomes the multiplier for that particular exercise. If I were to make an exercise and put in a different number of calories for that exercise for the same time, someone with the same body weight and height would get the same number as I did for the same time automatically, which means it takes that multiplier and uses it for that exercise, just changing the peripheral numbers for different calories (this get's very complicated if you let it, I WAS TOLD THERE WOULD BE NO MATH!)

arewethereyet

Yeah but Steve........when you enter walking 4.0 for 30 mins, and I enter the same thing we get different numbers. There has to be some sort of formula in the background

edit to add:

Walking, 3.5 mph, brisk pace 30 minutes 117 calories

yep, it takes into account your weight and height, and age and sex. But those are peripheral factors, it's still using a single multiplier, which isn't the same for everyone so while you may get close, it's an estimate based on the person who created the exercise.

so Mike has no set exercise like the food log?

right (I think, I can't be sure as I can't see his code) but based on how the site reacts, that's my belief. You may want to PM him to ask, I'd be curious.

I just entered Jeannie Bicycle kicks to my log and it is not in the main log. I do believe there is some sort a base for all of it. Otherwise you would also get 117 for your cals burned, right?

I know it is very very close to the HRM cals burned almost every time

no no I think what happens is it takes your calories burned, factors in all the numbers, then uses that percentage for anyone who uses this exercise at this level. And that becomes the multiplier for that particular exercise. If I were to make an exercise and put in a different number of calories for that exercise for the same time, someone with the same body weight and height would get the same number as I did for the same time automatically, which means it takes that multiplier and uses it for that exercise, just changing the peripheral numbers for different calories (this get's very complicated if you let it, I WAS TOLD THERE WOULD BE NO MATH!)

:laugh: :laugh: :laugh:

NO worries, I hate math too! That is why I married my hubby. He is good at math, I at spelling. He can take apart the engine, I can read the manual to put it back together!

I still think Mike has something in the background, it is just too darn close to my HRM numbers. Although I always wondered how the numbers were close when my body type is so different now than when I began. Not just weight wise.......expenditure wise.

Example- started ellip 400 cals burned in 30 minutes. Dying, sweating, did I mention dying?
Now- I get on Mr Ellip and 30 mins on 5 going 5.0 mph and burn 250 stinkin calories.

:ohwell: price to pay for being healthier

terence

I just checked my early numbers and my calorie expenditure is down for the same exercise. Not a lot however: 30 calories less for a very brisk walk. I'm doing it much, much easier than when I began.

Azdak

Yeah but Steve........when you enter walking 4.0 for 30 mins, and I enter the same thing we get different numbers. There has to be some sort of formula in the background

edit to add:

Walking, 3.5 mph, brisk pace 30 minutes 117 calories

yep, it takes into account your weight and height, and age and sex. But those are peripheral factors, it's still using a single multiplier, which isn't the same for everyone so while you may get close, it's an estimate based on the person who created the exercise.

so Mike has no set exercise like the food log?

right (I think, I can't be sure as I can't see his code) but based on how the site reacts, that's my belief. You may want to PM him to ask, I'd be curious.

I just entered Jeannie Bicycle kicks to my log and it is not in the main log. I do believe there is some sort a base for all of it. Otherwise you would also get 117 for your cals burned, right?

I know it is very very close to the HRM cals burned almost every time

no no I think what happens is it takes your calories burned, factors in all the numbers, then uses that percentage for anyone who uses this exercise at this level. And that becomes the multiplier for that particular exercise. If I were to make an exercise and put in a different number of calories for that exercise for the same time, someone with the same body weight and height would get the same number as I did for the same time automatically, which means it takes that multiplier and uses it for that exercise, just changing the peripheral numbers for different calories (this get's very complicated if you let it, I WAS TOLD THERE WOULD BE NO MATH!)

:laugh: :laugh: :laugh:

NO worries, I hate math too! That is why I married my hubby. He is good at math, I at spelling. He can take apart the engine, I can read the manual to put it back together!

I still think Mike has something in the background, it is just too darn close to my HRM numbers. Although I always wondered how the numbers were close when my body type is so different now than when I began. Not just weight wise.......expenditure wise.

Example- started ellip 400 cals burned in 30 minutes. Dying, sweating, did I mention dying?
Now- I get on Mr Ellip and 30 mins on 5 going 5.0 mph and burn 250 stinkin calories.

:ohwell: price to pay for being healthier

Calories are based on weight x intensity. As you lose weight, calories burned per unit of intensity will decrease also. Of course, the idea is that, if you are training consistently for improvement, your aerobic capacity should increase as well, meaning that the loss in weight should be offset somewhat by the ability to work at a higher intensity. Plus the decreased weight means that you should not need to exercise as much to maintain.

terence

Calories are based on weight x intensity. As you lose weight, calories burned per unit of intensity will decrease also. Of course, the idea is that, if you are training consistently for improvement, your aerobic capacity should increase as well, meaning that the loss in weight should be offset somewhat by the ability to work at a higher intensity. Plus the decreased weight means that you should not need to exercise as much to maintain.

It seems that I need to step up my routine. Walking just doesn't cut it anymore and I'm walking 2 hours or more each day to achieve the result. :ohwell:

On the positive side, only 6 lbs to go. See you at the starting line. :drinker:
After all, reaching one goal is just the beginning of the next (maintenance).