Q: Does running a mile burn more calories than walking a mile?
Running will involuntarily increase heart rate and produce a higher rate of oxygen consumption as opposed to walking. VO2 (or oxygen consumption) is a measure of the volume of oxygen that is used by your body to generate energy for your working muscles. Specifically, as exercise intensity increases (i.e. walk to run) there is a greater load of physical stress placed on your muscles forcing them to work harder than normal, as a result, they require more energy than normal. This response will spark an overall increase in muscular oxygen demands (VO2), thus creating a slightly higher caloric expenditure while traveling the same distance. That said, running or jogging a mile at a speed >4.0 mph on a flat surface may yield a somewhat higher caloric burn when comparing to walking a mile at a speed <4.0 mph. Furthermore, as an added bonus runners can expect to elicit a greater effect of EPOC (excess post-exercise oxygen consumption) which leads to even more caloric burn just after a run. In other words, the body expends more energy after running as opposed to walking in an effort to restore the body to its resting state.
Nuts & bolts: The disparity of energy expenditure between running and walking is marginal when it comes to equal shorter distances. The gap in calories burned will naturally become larger as equal distances increase. For example, walking 1 mile on a flat surface may yield 100 calories while running 1 mile on a flat surface may yield 120 calories. Therefore, a 5 mile distance would be approximately a 100 calorie difference. Of course, walking 5 miles at a pace of 4.0mph would take a person 75 minutes to complete compared to only 50 minutes if running at 6.0mph. Keep in mind that total calories expended is relative to an individual’s body weight. In addition, raising the incline feature on a treadmill or adding outdoor terrain can dramatically inflate these numerical figures.
Bottom line: An elevated VO2 is the major component causing a modest difference in caloric expenditure during a run/jog compared to walking at an equal distance.