Tuesday, November 20, 2012

Walking vs. Running: Which gives you the better "burn?"

As most of you who read my blog know, I'm an avid runner and have been for a long time. I ran my first cross-country race in 1994 at the age of 12, and haven't really let up much since. I've always preferred running to walking as it's simply a way to get you to where you need to go, faster.

During freshman year of college, I worked on one side of campus and lived on the other side. The walking distance from one end to the other was about 1 mile. More times than not, it would be bitterly cold (just ask anyone who has ever been to UMaine Orono during the winter), so I would set off running across campus after work because it got me to where I needed to go quicker than walking would have, and warmed me up nicely along the way. Now, this was waaaayyyyy before I ever got involved in all this health and fitness stuff, but I have wondered if this was one of the reasons I never gained the dreaded freshman 15. What do I mean? Well, a mile is a mile, right? Doesn't it take the same amount of energy to cover that distance regardless of whether you do it in 10, 20, or 30 minutes? I've heard both sides of the argument, with one side coming from a renowned scientist, and the other coming from the running community. Let's take a look...

The first argument (well, it wasn't even really an argument at all--it was more of a statement) came from a very respected and well-known scientist at a fitness equipment manufacturer that I visited this past summer. The statement was simple and bold: "You burn just as many calories walking as you do running when travelling an equal distance." Really? This is fantastic! So my clients can either run or walk 3 miles and they will both burn just as many calories as the other.

After sharing this exciting news with several of my clients, I decided to dig around a little bit. There is an old-school way of thinking and it goes something like this: No matter how fast you move, if travelling over level ground, you will burn about 100 calories per mile. Whether you walk, sprint, crawl, run, or do any combination thereof, you will burn about 100 calories over that distance.


Well maybe, but not really. What am I talking about? Well, a study was done by the Washington University School of Medicine that took a look at perceived exertion levels of running and walking at various speeds. The subjects of the study were asked to walk at various speeds ranging from 4 to 10.4 km/hour for 5 minutes and run for 5 minutes at 7.2 to 10.4 km/hour. The conclusion drawn was basically this: There is a point when walking becomes more difficult than running, and that you when you hit this point, you will burn more calories walking than running. This point is 5 miles per hour.

Ok, so the good doctor's statement is supported! Right?

Well, there is now a new-school train of thought that has come around.

This past spring, a group of researchers from California State University published a research paper that firmly supported the theory that running burned more calories than walking. The test was done with 30 college-aged students (15 males and 15 females) averaging 156 pounds. They were asked to run a treadmill mile in 10:00 minutes on one day and to walk a treadmill mile in 18:36 on another day. After each session, they sat quietly for 30 minutes so that their metabolic rate would slow down.  It was determined that the participants burned almost 3 times as many calories per minute (4.78 for walking versus 11.25 for running) when they ran as compared to when they walked. When taking excess post-exercise oxygen consumption (EPOC, or the "after burn") into consideration, the difference between running and walking was even greater.

Interesting, right? Well, hold on. The study does have a few caveats. For one, the study was done on an "average" of participants, with each "averaging" 156 pounds. According to the study, weight, along with age, is a huge factor in how many calories a person can burn, due to how fast one can run. To figure how many calories per mile you might burn while walking, multiply .57 by weight in pounds. For running, the calculation would  be .72 x weight in pounds. This should give you a general idea of how many calories you are burning per mile.

So which one of these schools of thought is correct? Well, they both are, really. There can't really be a definitive number given to how many calories you burn when walking or running at different speeds. There just can't. The more efficient you become at it, the fewer calories your body will burn while performing what it is that you are doing. Perhaps your preferred run-walk transition speed (PTS) can shed some light on this. That is, if you run at a slower speed than your PTS, it will feel harder and you will expend more calories. The same can be said for the opposite: If you walk at speeds higher than your PTS, it will feel harder and you will burn more calories. Intervals, anyone?

Still confused? Probably. My advice to you is that if you can run, then run. If you can't run for whatever reason (bad knees, hips, back, etc.) then walk as fast as you can at a sustainable speed. Or as I mentioned above, give intervals a shot. The most important this is getting your 30-60 minutes of activity per day.

No comments:

Post a Comment