Revision as of 14:27, 29 July 2013

You can measure Calories burned two ways; Calories over time or Calories over distance. For running, you burn the same number of Calories to cover a given distance regardless of pace. The number of Calories burned running depends only on your weight and the slope. For walking, your pace also makes a difference; the faster you walk the more Calories it takes to cover the distance. There are various formulas for calculating Calories burned^[1][2], but there is a wide variation based on Efficiency. For instance Paula Radcliffe improved her Running Economy by nearly 20% over 10 years. The tables below default to showing values for a 150 pound person, but you can use the form at the bottom of the page to generate tables specific to your body weight. (Selecting Kg will change the distances units to Km.)

1 The Difference Between Running and Walking

Running and walking are two different forms of movement. In running you either have one foot on the ground or both feet in the air; both feet are never on the ground at the same time. In contrast, when walking you either have one or both feet on the ground and never have both feet in the air.

2 The Transition Between Running and Walking

The energy required to run a given distance is the roughly the same regardless of pace. This is different to walking, where the energy required to walk a given distance generally goes up with pace. This means that at slow speeds, it costs less energy to walk than run, but as you go faster it becomes easier to run. When people are put on a treadmill and the speed gradually increased, they will naturally transition from walking to running. This transition occurs at roughly the same speed for most people and is called the Preferred Transition Speed (PTS)^[3]. You can see this in the two graphs below. The graph on the left shows the energy expenditure over time, showing the energy required to walk goes up faster than for running. The graph on the right shows the cost per distance, with running staying constant and the cost of walking rising with pace. (It takes more energy to walk a distance very slowly, so the graph shows the low point which is the lowest energy cost to cover a distance.)

Energy cost over time.

Energy cost over distance.

3 Calories Per Hour

This table shows the number of Calories used per hour for a person weighing 150 Pounds.

4 Calories Per Distance

This table shows the number of Calories used to cover a milefor a person weighing 150 Pounds.

5 Constant Effort

This table shows how the slope would change your pace if you keep the same effort (Calories per hour). The first column is the running pace on the flat, then each column shows the pace you would travel if you run or walk on various slopes.

6 Input Form

Use this form to generate a table for your weight. Selecting Kg for the units will also change the distance from Miles to Km.

7 Training Status Effects

The graph on the below shows that there are slight, non-significant differences between runners and active non-runners. This indicates that training does not change the transition speed, though it’s worth noting that the actual transition speed is slower than would be expected from the energy costs^[3]. Also note that the actual cost of running is not quite constant with speed, but actually goes down as you go faster.

The energy cost for runners and non-runners, showing the Preferred Transition Speed (PTS) and the Energetically Optimal Transition Speed (ETOS).

8 References

1. ↑ B. Givoni, RF. Goldman, Predicting metabolic energy cost., J Appl Physiol, volume 30, issue 3, pages 429-33, Mar 1971, PMID 5544128
2. ↑ AE. Minetti, C. Moia, GS. Roi, D. Susta, G. Ferretti, Energy cost of walking and running at extreme uphill and downhill slopes., J Appl Physiol, volume 93, issue 3, pages 1039-46, Sep 2002, doi 10.1152/japplphysiol.01177.2001, PMID 12183501
3. ↑ ^{3.0 3.1} A. Rotstein, O. Inbar, T. Berginsky, Y. Meckel, Preferred transition speed between walking and running: effects of training status., Med Sci Sports Exerc, volume 37, issue 11, pages 1864-70, Nov 2005, PMID 16286854