TOTAL cal burn VS NET cal burn??

CocoNuttie

Hi,

I've been using this site for a while now, sucessfully. However, I've always been quite confuse about the amount of calories burned during exercise on the mfp. I've been running a lot lately and wanting to find an accurate way of measuring how much I burn (without buying an HRM!). I'm quite small, so I have a very small room to wiggle in term of calories. Anyway, I came across this while researching on the internet. It's an article about calorie burn walking VS running, but what really interest me is the section below


....."Now that you understand why running burns 50 percent more calories per mile than walking, I hate to tell you that it's a mostly useless number. Sorry. We mislead ourselves when we talk about the total calorie burn (TCB) of exercise rather than the net calorie burn (NCB). To figure the NCB of any activity, you must subtract the resting metabolic calories your body would have burned, during the time of the workout, even if you had never gotten off the sofa.

You rarely hear anyone talk about the NCB of workouts, because this is America, dammit, and we like our numbers big and bold. Subtraction is not a popular activity. Certainly not among the infomercial hucksters and weight-loss gurus who want to promote exercise schemes. "It's bizarre that you hear so much about the gross calorie burn instead of the net," says Swain. "It could keep people from realizing why they're having such a hard time losing weight." ........


What's the Burn? A Calorie Calculator
You can use the formulas below to determine your calorie-burn while running and walking. The "Net Calorie Burn" measures calories burned, minus basal metabolism. Scientists consider this the best way to evaluate the actual calorie-burn of any exercise. The walking formulas apply to speeds of 3 to 4 mph. At 5 mph and faster, walking burns more calories than running.

RUNNING
Your Total Calorie Burn/Mile = .75 x your weight (in lbs.)
Your Net Calorie Burn/Mile = .63 x your weight

WALKING
Your Total Calorie Burn/Mile = .53 x your weight
Your Net Calorie Burn/Mile = .30 x your weight

Adapted from "Energy Expenditure of Walking and Running," Medicine & Science in Sport & Exercise, Cameron et al, Dec. 2004. "


Now I find that quite interesting and I have to say I quite agree. Is that mean I shouldn't eat all my exercise cal back? you can't eat you bmr AND exercise cal back....

So, according to my run today, the total BURN is 560cal and NET is 471cal....mfp gives me 569cal. It is more than 100cal different...and if you're working out 5 days a week.... that's a missed calculation by 500cal/week.

Please try your number and see if it comes out much different too! let me know

GreenLifeGirl

this article is from runnersworld, right?

CocoNuttie

this article is from runnersworld, right?

Oh yes, I forgot to leave the link! Thank you

http://www.runnersworld.com/article/0,7120,s6-242-304-311-8402-0,00.html

persian_star

I read the same article a while back (I'm a walker, so I was interested to see the difference to being a runner) and despite seeing the sense of it, have failed to put it into practice with my numbers at all!

2 weeks ago I finally got a HRM (Polar FT40) which I love, but it's left me even more confused! Not only do my numbers now fluctuate between 160 cals and 230 cals for my 32 min, 2 mile walk (to and from work), but it suddenly dawned on me the other day that I had no idea if the HRM was counting my net calories, i.e. taking into account all my stats and working the BMR cals for that time in, or whether it was gross, and I should be removing my bmr cals myself!

My BMR is 1350, so that's just shy of 1 cal per minute. If I burned, say 180 cals on my walk, would I then need to subtract 30 for my BMR?

I don't remember seeing ANYWHERE whether HRM's give net or gross cals, so if anyone can illuminate, that would be really helpful.