By Amy Burfoot
Two weeks ago, I began planning an update to a walking vs running calorie-burn article that I had written for Runner’s World magazine in 2005. When that article subsequently appeared on the RunnersWorld.com website, it attracted a lot of interest and comments. Some of those comments displayed the widespread confusion and outright disbelief that’s common to this topic.
Most people believe that walking one mile and running one mile burn the same number of calories. You know, a mile is a mile is a mile. Sounds reasonable. But it doesn’t hold up to scientific scrutiny.
So I thought I’d write another blog post to clarify the confusion as much as I can. Fortunately, I got some help. A group of researchers from California State University have just published a new run vs walk paper. It’s the best one yet, and it confirms (to a very high degree) the data I presented in 2005, which was mostly based on this paper. Even better, this group of investigators have included the “after burn” in their calculations. That’s a first.
It’s also entirely appropriate. Whether you finish your workout by collapsing on the grass, drinking a smoothie, or taking a shower, your body continues burning more calories than usual until it returns to its basal metabolic rate. These calories are “free,” yet real.
The subjects in the new study were 15 male college students, and 15 female, with an average weight of 156 lbs. One day they ran a treadmillmile in 10:00 minutes; another day they walked a mile in 18:36. Afterwards, they sat quietly for 30 minutes, by which time their metabolic rate had returned to normal.
Table A: Calories Burned Per 1-Mile Walk vs 1-Mile Run For A 156-lb Subject
*one mile walk in 18:36; ** one mile run in 10:00
I always add a calories/minute result to these calculations, because, frankly, it’s how most of us live our lives. We only have so manyworkout minutes in a day or week, and we’d like to know what the payoff is. Clearly, running burns more than twice as many calories per minute (11.25) as walking (4.78). This difference increases when you consider the after-burn.
However, you have to be careful about the way you apply the after-burn. You only get one after-burn per workout, not one per mile. So if you run five miles, your after-burn might still be just 46.1 calories (or minimally higher). You don’t get to multiply five by 158.6 calories/mile, which would yield 793 calories burned. Instead, you should multiply five by 112.5, and then add 46.1. That yields 608.6.
Probably it’s smartest to just multiply your total miles by 112.5, and consider the after-burn a nice little bonus. To increase your bonus, run faster during your workout. One recent study showed that a modestly-hard workout could produce 190 after-burn calories in the following 14 hours.
Lastly, I like to produce calorie-burn charts that adjust to your body weight. As noted, the above chart only works if you weigh 156.2 pounds. Which you probably don’t. Here’s a very simple chart that lets you compute your personal calorie-burn per mile per pound.
Table B: Your Calorie Burn Per Mile (Or Minute) Walk vs Run
|CALORIES/MILE||.57 x wt in lbs||.72 x wt in lbs|
|CALORIES/MIN||.03 x wt in lbs||.07 x wt in lbs|
To use the above, simply multiply your weight (in pounds) by the number shown. For example, if you weigh 188 lbs, you will burn about 107 calories (188 x .57) when you walk a mile, and about 135 calories (188 x .72) when you run a mile.
As you can see, running a mile burns roughly 26 percent more calories than walking a mile. Running a minute (or 30 minutes, or an hour, etc.) burns roughly 2.3 times more calories than the same total time spent walking.
OK, now a few caveats. These calculations are all derived from an “average” weight of the subjects; there may be individual variations. Also, age and gender make a difference, though quite a modest one. Your weight is by far the biggest determinant of your calorie burn per mile. When you look at per-minute burn, your pace (your speed) also makes a big difference.
These calculations aren’t meant to be precise. They are good approximations, and much more accurate than the old chestnut: You burn 100 calories per mile.
Lastly the calculations only apply to walkers doing an 18:36 pace and runners doing a 10:00 pace. Running faster or slower than 10:00 pace doesn’t make much difference in your calorie-burn per mile. (But has a major impact on your burn per minute.)
Walking is a different kind of animal. Increases in walking speed dramatically raise calorie burn per mile as well as per minute. Indeed, at about 12:30 per mile, walking hits a point where it burns about the same calories/mile as running. Walk faster than 12:30 and you will burn more calories/mile than running at 10:00 pace.
However, almost no one but competitive race walkers goes faster than 12:30 per mile. Indeed, when I look out my front window at walkers circling the block, very few are walking faster than 18:36. Most are in the 18:00 to 20:00 range—great exercise for the elderly and the overweight, but not a big calorie-burn activity.
Finally, this time around I haven’t made a distinction between net calorie burn and gross calorie burn, which is what you’ll get by doing the math shown above. The net versus gross argument is important to some people, but, frankly, it’s almost never reported in health and journalism circles, and is probably more complicated than most people want to know.
Do what you can to burn as many calories as possible in exercise and daily living. That’s the ticket to good health and weight. (Some individuals take this too far, but they are in the distinct minority, and don’t constitute a national public health crisis. I just read a health economics paper that estimates 20 percent of national health care costs are related to obesity-related illnesses.)
Source: Women’s Health Magazine | not affiliated with Aetrex Worldwide