How many calories do you burn while walking?
Despite the quantity of scientific research and the vast information regarding energy expenditure while walking, jogging cycling and running, there are different misconceptions to dispel. The most common misconception is that the caloric cost of walking is the same as jogging over a distance of one kilometer.
This is incorrect and here’s why.
To assess the energy expenditure of walking or jogging you can use many formulas based on previous research. Knowing the caloric cost of your physical activity can be important to set short and long term goals.
It is well known that the caloric equivalent of one litre of oxygen (O2) is 5.0 kcals for carbohydrate, 4.7 kcals for fat and 4.5 kcals for protein. Therefore, when walking at a velocity of 5.0 km/h or 83.4 m/min for a duration of 12 minutes to cover a total distance of 1 kilometer, a man weighing 70 kg would have a VO2 = 83.4 m * min-1 * 0.1 ml * kg-1 + 3.5 ml * kg-1 * min-1.
VO2 = 11.84 ml * kg-1 * min-1.
VO2 (ml * km-1) = 11.84 ml * kg-1 * min-1 * 70 kg * 12 min * km-1 = 9945.6 ml * km-1.
VO2 (l * min-1) = 9945.6 ml * km-1 / 1000 ml * l-1 = 9.9456 l * km-1.
When considering 5.0 kcal per one l/O2 the energy expenditure of walking at 5.0 km/h for one kilometer would be estimated at 49.72 kcal (5 kcal * 9.9456 l * km-1).
How many calories do you burn while jogging?
Instead, if the same person performs one kilometer of jogging in 6 minutes and 15 seconds, at 9.6 km/h thus 161 m/min, caloric expenditure would total at 78.09 kcal. This data was estimated via the following equation:
VO2 = 161 m * min-1 * 0.2 ml * kg-1 + 3.5 ml * kg-1 * min-1.
VO2 = 35.7 ml * kg-1 * min-1.
VO2 (ml * km-1) = 35.7 ml * kg-1 * min-1 * 70 kg * 6.4 min * km-1 = 15993.6 ml * km-1.
VO2 (l * min-1) = 15993.6 ml * km-1 / 1000 ml * l-1 = 15.9936 l * km-1.
Therefore, when estimating 5.0 kcal per litre of O2 the energy expenditure when covering a distance of one kilometers at 9.6 km/h would be 79.96 kcal (5 kcal * 15.9936 l * km-1).
Using these two simple equations you can estimate the caloric cost of your activity, don’t forget however this only applies to walking or running on a flat surface.
Edward T. Howley - B. Don Franks. “Manuale dell’istruttore di Fitness”, 2002.