My engineer friend was arguing that it takes the same amount of energy to walk say a 15 min. mile as it takes to run a 4 min. mile. He says that this is basic physics.
I don't know physics from a hole in the ground but to me it seems like common sense that it would take more energy to run faster. Is what he says true or is he pulling my leg?
Never trust an engineer in a real world scenario.
This is not a good source because it compares calories per minute as opposed to calories per mile.
OP- There is not exactly basic physics going on here. It basically comes down to efficiency. Running is less efficient than walking, so it uses more calories. Doing forward moving jumping jacks is less efficient than running, so it uses more calories.
Yes, this is not true. Ask your friend if he knows anything about wind resistance.
mgdhm,hdt wrote:
False.
http://www.brianmac.co.uk/energyexp.htm
That page doesn't really answer the question. It is measuring in energy per unit time (i.e. power).
To answer the OP's question, I will plug in a few numbers.
Runner at 16km/hr, running for 6 minutes (so 1600 meters), 68kg of weight: 110 calories
Walker at 4km/hr, running for 24 minutes (so 1600 meters), 68kg of weight: 84 calories
So your friend is wrong according to that calculator. It has to do with efficiency of the stride. There is more wasted energy in running than in walking. One thing that is interesting to note is that the speed you walk doesn't change how much energy you spend walking per unit of distance as long as you are walking at reasonable paces. So walking 2mph burns a very similar number of calories per mile as walking at 4mph. Walking at 6mph is going to burn more because you are becoming inefficient. Same with running, a runner going 6mph is going to burn similar numbers of calories per distance while running at 10mph. Try to run 17 or 18 mph and you are now going to start burning more calories per distance because you are becoming inefficient again.
Like others have said walking a mile takes less energy because it is more efficient. Air resistance increases with the square of velocity, running oscillates your centre of mass against gravity to a greater extent, more energy is spent doing work to accelerate the limbs to higher velocities, energy losses during inelastic collisions and losses during elastic return, there are loads of factors. I can't be bothered to do the numbers to find out which factors dominate. Instinct tells me it is acceleration of the centre of mass against gravity.
This is one of those very old myths that will probably never go away.
Physics Ignoramus wrote:
My engineer friend was arguing that it takes the same amount of energy to walk say a 15 min. mile as it takes to run a 4 min. mile. He says that this is basic physics.
I don't know physics from a hole in the ground but to me it seems like common sense that it would take more energy to run faster. Is what he says true or is he pulling my leg?
Fact 1) Running gets one from point A to point B faster than walking
Fact 2) IF running were as energy efficient as walking THEN there would be ZERO advantages to walking rather than running
Fact 3) And yet, walking is the chosen mode of transport for most people most of the time (sans auto, bike, etc). This is true in every single society in the world, both modern and primitive.
It follows, as night follows day, that walking ABSOLUTELY MUST BE more energy efficient than running. Otherwise, no such mode of transportation would have ever evolved.
QED
Logical Person wrote:
Fact 1) Running gets one from point A to point B faster than walking
Fact 2) IF running were as energy efficient as walking THEN there would be ZERO advantages to walking rather than running
Fact 3) And yet, walking is the chosen mode of transport for most people most of the time (sans auto, bike, etc). This is true in every single society in the world, both modern and primitive.
It follows, as night follows day, that walking ABSOLUTELY MUST BE more energy efficient than running. Otherwise, no such mode of transportation would have ever evolved.
QED
1) Fast walking may or may not be more energy efficient than jogging slowly.
2) Walking really slowly is less energy efficient than walking normally. That doesn't imply anything about any advantages or disadvantages.
3) You're an idiot. QED.
Logical Person wrote:
Fact 2) IF running were as energy efficient as walking THEN there would be ZERO advantages to walking rather than running
That's not quite true. The advantage would be that the power requirement would not be as high. It takes resources to build a powerful motor.
Also something I forgot to mention is that there is actually a speed-dependent efficiency crossover between running and walking. Walking become less efficient than running above something like 10 minutes per mile (don't quote me on that, I really can't remember the value) due to the body's inability to utilise elastic return correctly when walking very quickly. I've seen a study on this. I'll see if I can find it online.
Crazy race-walkers. That sport's gonna get someone killed one day.
Physics Ignoramus wrote:
My engineer friend was arguing that it takes the same amount of energy to walk say a 15 min. mile as it takes to run a 4 min. mile. He says that this is basic physics.
I don't know physics from a hole in the ground but to me it seems like common sense that it would take more energy to run faster. Is what he says true or is he pulling my leg?
There are a variety of reasons I'd rather not waste my time on bringing up, but one of the most obvious that you and your friend should easily see is that the air resistance during a 4 minute mile is much greater than that experienced when doing a mile in 15 minutes.
people walk because they are not in shape enough to run places they would normally walk too, and would get too sweaty running.
Logical Person wrote:
Physics Ignoramus wrote:My engineer friend was arguing that it takes the same amount of energy to walk say a 15 min. mile as it takes to run a 4 min. mile. He says that this is basic physics.
I don't know physics from a hole in the ground but to me it seems like common sense that it would take more energy to run faster. Is what he says true or is he pulling my leg?
Fact 1) Running gets one from point A to point B faster than walking
Fact 2) IF running were as energy efficient as walking THEN there would be ZERO advantages to walking rather than running
Fact 3) And yet, walking is the chosen mode of transport for most people most of the time (sans auto, bike, etc). This is true in every single society in the world, both modern and primitive.
It follows, as night follows day, that walking ABSOLUTELY MUST BE more energy efficient than running. Otherwise, no such mode of transportation would have ever evolved.
QED
teacher of logics wrote:
Logical Person wrote:Fact 1) Running gets one from point A to point B faster than walking
Fact 2) IF running were as energy efficient as walking THEN there would be ZERO advantages to walking rather than running
Fact 3) And yet, walking is the chosen mode of transport for most people most of the time (sans auto, bike, etc). This is true in every single society in the world, both modern and primitive.
It follows, as night follows day, that walking ABSOLUTELY MUST BE more energy efficient than running. Otherwise, no such mode of transportation would have ever evolved.
QED
1) Fast walking may or may not be more energy efficient than jogging slowly.
2) Walking really slowly is less energy efficient than walking normally. That doesn't imply anything about any advantages or disadvantages.
3) You're an idiot. QED.
You appear to have a severe deficiency in logical circuitry.
If walking did not have an energy advantage over running then the human species would never have evolved to walk.
Please try to think. I know that this would be asking a great deal of you - possibly more than you are capable of. Still, give it a try. You might find it a refreshing change from your miserable, ignorant existence.
have to say it wrote:
people walk because they are not in shape enough to run places they would normally walk too, and would get too sweaty running.
Walking would not even exist as a gait in the human species if it did not have the advantage of energy efficiency.
Limey UK runner wrote:
Logical Person wrote:Fact 2) IF running were as energy efficient as walking THEN there would be ZERO advantages to walking rather than running
That's not quite true. The advantage would be that the power requirement would not be as high. It takes resources to build a powerful motor.
Also something I forgot to mention is that there is actually a speed-dependent efficiency crossover between running and walking. Walking become less efficient than running above something like 10 minutes per mile (don't quote me on that, I really can't remember the value) due to the body's inability to utilise elastic return correctly when walking very quickly. I've seen a study on this. I'll see if I can find it online.
Crazy race-walkers. That sport's gonna get someone killed one day.
Your argument does not hold up. Given that the 'resources to build a powerful motor' are built into the human species for purposes of running, the existence of the walking gait in the human species does NOT save the need to build and maintain such power. As such, this is NOT an advantage of walking.
Again, given that running exists as a form of transportation the only possible reason that walking also exists is that it is more energy efficient.
QED
Logical Person wrote:
Your argument does not hold up. Given that the 'resources to build a powerful motor' are built into the human species for purposes of running, the existence of the walking gait in the human species does NOT save the need to build and maintain such power.
QED
Looks like my comment about resources served to confuddle rather than inform. I was referring to environmental pressures during evolution but I realise I wasn't very specific on this. Let me try a different approach.
In animal energy systems higher power output is associated with lower fuel economy. Choosing to operate at a lower fuel economy is disadvantageous if all other factors are equal.
You will not change my stance on race-walkers being crazy bast*rds.
FACT: Running a mile is a waste of time.
You don't get JACKED, you don't get RIPPED. What is the point? So you can say you ran a mile? Seriously?
Xfit_guy_the_real_1 wrote:
FACT: Running a mile is a waste of time.
You don't get JACKED, you don't get RIPPED. What is the point? So you can say you ran a mile? Seriously?
Your man parts must be really tiny.
Limey UK runner wrote:
Logical Person wrote:Your argument does not hold up. Given that the 'resources to build a powerful motor' are built into the human species for purposes of running, the existence of the walking gait in the human species does NOT save the need to build and maintain such power.
QED
Looks like my comment about resources served to confuddle rather than inform. I was referring to environmental pressures during evolution but I realise I wasn't very specific on this. Let me try a different approach.
In animal energy systems higher power output is associated with lower fuel economy. Choosing to operate at a lower fuel economy is disadvantageous if all other factors are equal.
You will not change my stance on race-walkers being crazy bast*rds.
Gonna have to agree about race walkers. I simply cannot fathom some kid watching this Olympic 'sport' and dreaming of growing up to be a race walker some day.
Thanks for those of you giving serious answers. Maybe my buddy was messing with me or or maybe talking about some sort of ideal conditions with wind resistance, etc.