Obviously different paces and different sized runners will change the rate at which a runner burns calories. Does anyone know of a chart that can give varying approximations of how many calories a person burns at what speed/length of time?
Holding pace constant, calories burned are proportional to the length of time (i.e. 60 minutes consumes twice as many as 30 minutes). If you increase the pace, the calories burned are proportional to the increase in pace, but calories consumed are the same because you finish sooner. However, a walker will burn approximately as many calories as a runner. It will just take them longer.
There is a slight difference actually, something in the range of 10-15% between walkers and runners. This is because in running you have more upper body movement and you pick your feet higher off the ground. But essentially pace doesn't matter, I've heard something around 100 calories a mile for 150 pounds.
Oxygen cost of running (ml/kg/min) = 0.2 x velocity (meters/min).
1kcal burned uses approx. 4.83L of Oxygen.
A 65kg person runs at 6:00/mile (268m/min) for 60 mins.
VO2 = 0.2 x 268 = 53.6 ml/kg/min
53.6ml/kg/min x 65kg = 3.48L/min
3.48L/min x 4.83kcal/L = 16.80 kcal/min
16.80kcal/min x 60min = 1008.5 kcal
Is that carved in stone or does it vary person to person? For example a more efficient 65KG person runs 6:00 per mile for 60 minutes. Is his VO2 less than 53.6 and does he burn less calories?
The amount of O2 used per kcal burned depends on your respiratory exchange ratio (R), or generally your diet. A 100% carbo diet yields 5kcal per litre O2 whereas a mixed diet yileds 4.83kcal per litre O2. An athlete can figure out at exactly what rate he is burning calories by measuring R from a high-tech spirometer. A 100% carbo diet yields a R=1.00 whereas a 70% diet yields R=0.81 (if I remember off the top of my head correctly, I'll check it out).
While these levels aren't "set in stone" they are pretty accurate for an athletic population. The formula V02 = 0.2 x velocity is what treadmill manufacturers use to approximate how many calories you are burning based on the velocity setting of the 'mill.
I\'m not sure of the accuracy of the chart, but this website seems to fit in pretty well with the equation, and it is fairly comprehensive:
and just so you know, a 900 pound 8 year old kid that is 3\'11\", harvesting wild rice from a canoe for 26 hours will burn 22,316 calories.