Ever since Sir Isaac Newton put quill to paper and created his laws of motion, the branch of physics that deals with the force exerted on objects that causes them to move, people have looked at running and walking as virtual equals. Both move a body from one place to another. Since the body doesn't change -- your weight stays the same whether you're walking or running -- it should take the same amount of energy to move your body, no matter how you move it. If that wasn't enough, walking and running use up the same amount of energy; in other words, they burn the same amount of calories.
Yet, joggers had long noticed that walking and running produced different results when it comes to weight loss, or a person burning more calories than he or she takes in. It would seem that running in fact does burn more calories than walking.
In 2004, a group of Syracuse University researchers got around to quantifying what the jogging community had already noted. A trial of 24 men and women both running and walking on a treadmill resulted in more calories burned during the running segment than during walking 1,600 meters, or about one mile. The men burned 124 calories running, on average while the women burned an average of 105. When walking men burned an average of 88 calories and women burned an average of 74 calories. Overall, running burned 114.8 calories and walking burned an average of 81.2 calories [sources: Burfoot, Hall et al].
What the researchers found wasn't a flaw in Newtonian physics. Instead, they pointed out that people who thought running and walking required the same energy were overlooking a major point: They don't. Running actually requires more. How did they miss something so important? Find out on the next page.
Weight, Energy and Calories
Look again at the results of the Syracuse University study. Men burned more calories than women during both segments because they weigh more. Moving a body that weighs more requires more energy; hence, it burns more calories. The difference between running and walking is similar to the difference in weight, physicswise. Walking requires far less movement than running does.
Consider what Runner's World writer Amby Burfoot points out. When we walk, we maintain a level center of gravity and we propel ourselves by sticking our legs out one at a time and bending slightly at the knee as they carry that center of balance forward. Running, on the other hand, is far more complex and involves much more effort than walking. When a human runs, he or she achieves forward movement by essentially hopping from one foot to the other. Each hop requires the entire bulk of the person to be lifted from the ground and pushed forward. This distinction in motion explains why running burns more calories than walking -- it just requires more energy [source: Burfoot].
So how many calories does running burn? Again, weight is a major factor. So, too, is the distance the person runs and the duration. The Mayo Clinic uses the general rule of thumb that a runner can calculate the approximate amount of calories he or she burns during a run simply by multiplying one's weight in pounds by 0.75. For a 160-pound person (73 kilograms), running a mile burns 120 calories. Remember that duration and distance are also factors as well. If that same person runs eight miles (12.8 kilometers) in one hour (or eight miles per hour), he or she will burn approximately 986 calories [source: Mayo Clinic].
For more information on running and energy, see the links on the next page.
Does running fight depression? Visit HowStuffWorks to find out if running fights depression.
- Burfoot, Amby. "How many calories are you really burning?" Runner's World. August 2004.http://www.runnersworld.com/article/0,7120,s6-242-304-311-8402-0,00.html
- Hall, C., et al. "Energy expenditure of walking and running: comparison with prediction equations." Medicine and Science in Sports and Exercise. December 2004.http://www.ncbi.nlm.nih.gov/pubmed/15570150
- Mayo Clinic. "Exercise for weight loss: calories burned in 1 hour." December 1, 2009.http://www.mayoclinic.com/health/exercise/SM00109