"The" Question: Does running 10 miles at an easy intensity burn the same calories as 10 miles at a hard pace?

In regarding the excess post oxygen consumption. I understand the body must repair itself after a hard bout of work, but heart rate returns to normal after a short period. How can it be the body is still burning any extra calories?

effort=energy
Answer to question: No

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deleuze wrote:

The only thing this thread proves definitively that letsrunners suck at physics.

The only one with any sense on this thread is Alan. No way you can get a reasonable conclusion starting from basic principles. The act is too complex. Good physics runs from the empirical to the abstract but almost everyone on this thread is running their reasoning backwards.

Insults out of the way, A few points:

1. In the work equation the distance is constant but why would we assume the same force is applied at different speeds?

2. The increased effort of running faster is related to increased power demands not energy demands. Of course running faster requires more power -- whether it requires more energy is a question of efficiencies not effort.

3. The question of whether energy is used during or after the run is irrelevant... Here the physics is absolutely clear. The body can be treated as a mechanical system. But even then just as a motor vehicle has efficient velocities and inefficient velocities due to hearing there should be some variation from runner to runner.

4. All things considered the differences in energy efficiencies at different speeds should be very slight compared to the work done in moving the body over 10 miles. For that reason the fact that running at 8 minute miles vs 6 minute miles ought not be too different in terms of total energy requirements. However, the POWER requirements are totally different and that's the main thing in running.

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Alan pretty much summed it up. We've got pretty good scientific caloric data for running at slower paces versus walking. Walking burns quite a bit less.

Generally, running at different paces is considered to use similar amount of calories to cover the same distance, as the work that needs to be done is more or less the same. It certainly takes a few more calories the faster you go, as the impact of wind resistance becomes greater but at typical running speeds wind resistance isn't a huge factor. I'm sure this varies from person to person, as some people are probably more wasteful/less efficient as they get faster and/or slower, but as a general rule calories end up being similar regardless of whether you run 5:00 or 10:00 pace

Sprinting certainly uses a significantly greater amount of calories per distance as wind resistance becomes a huge player as you approach 20mph and beyond.

Wind speed may be factor but the major factor is the relationship between intense running and greater energy inefficiency. In my thought experiment of sprinting as hard as you can every other mile for a ten mile race versus running at an easier pace for 10 miles, the greater deletion of your energy stores at the end of the race when sprinting intervals would be true regardless of the wind speed factor. If your ran a ten mile race with intense 1 mile intervals on a treadmill, which has no wind factor, you still would have the same effect.

No energy left at the end. Running speed and intensity increases relative energy use per unit of distance.

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LM wrote:

Alan pretty much summed it up. We've got pretty good scientific caloric data for running at slower paces versus walking. Walking burns quite a bit less.

Generally, running at different paces is considered to use similar amount of calories to cover the same distance, as the work that needs to be done is more or less the same. It certainly takes a few more calories the faster you go, as the impact of wind resistance becomes greater but at typical running speeds wind resistance isn't a huge factor. I'm sure this varies from person to person, as some people are probably more wasteful/less efficient as they get faster and/or slower, but as a general rule calories end up being similar regardless of whether you run 5:00 or 10:00 pace

Sprinting certainly uses a significantly greater amount of calories per distance as wind resistance becomes a huge player as you approach 20mph and beyond.

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As glycogen levels are depleted, the body will switch to fat metabolism to supply it\'s energy.. The prevailing wisdom is that one has enough glycogen stores to run 20 miles-so say somewhere between 2 and 3 thousand calories if you burn 120 calories a mile. Running out of glycogen is when marathoners \"hit the wall.\" But this happens to some degree even if glycogen reserves are not completely emptied. As glycogen is depleted-not necessarily even down to the bottom of the tank, the properly evolved human will naturally switch over to fat burning. This will occur until the glycogen stores are refilled.

Long story short, calories are not calories. Glycogen or carbs are burned much more efficiently than fat-and fuel most of your daily activity. Fat allows you to survive the long winter while you are searching for buried potatoes to fill your starving belly. Go run 15 miles, and then eat a can of tuna fish, with a dollop of butter. You will soon feel the urge to go in the backyard and start digging up last year\'s potatoes.

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Conundrum wrote:

Wind speed may be factor but the major factor is the relationship between intense running and greater energy inefficiency. In my thought experiment of sprinting as hard as you can every other mile for a ten mile race versus running at an easier pace for 10 miles, the greater deletion of your energy stores at the end of the race when sprinting intervals would be true regardless of the wind speed factor. If your ran a ten mile race with intense 1 mile intervals on a treadmill, which has no wind factor, you still would have the same effect.

No energy left at the end. Running speed and intensity increases relative energy use per unit of distance.

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LM wrote:

Alan pretty much summed it up. We've got pretty good scientific caloric data for running at slower paces versus walking. Walking burns quite a bit less.

Generally, running at different paces is considered to use similar amount of calories to cover the same distance, as the work that needs to be done is more or less the same. It certainly takes a few more calories the faster you go, as the impact of wind resistance becomes greater but at typical running speeds wind resistance isn't a huge factor. I'm sure this varies from person to person, as some people are probably more wasteful/less efficient as they get faster and/or slower, but as a general rule calories end up being similar regardless of whether you run 5:00 or 10:00 pace

Sprinting certainly uses a significantly greater amount of calories per distance as wind resistance becomes a huge player as you approach 20mph and beyond.

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JG in CT wrote:

RW has a great piece related to this:

http://www.runnersworld.com/peak-performance/running-v-walking-how-many-calories-will-you-burn

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The take away from all this is that, yeah you probably burn a few more calories but not enough to worry about.

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Long story short, I'm not going to dismiss that as incorrect, but it doesn't seem inherent to me that faster running is less metabolically efficient; and what I can remember reading I haven't found much to suggest there is a strong correlation there. I'm definitely curious about the issue in general, so if you know any studies that look at running efficiency, especially relative to pace, I'd love to check them out

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Runningart2004 wrote:
There is a simple mathematical formula that calculates calories burned. Google it.

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3. Calories burned over a 24 hour period following higher intensity exercises exceeds calories burned over a 24 hour period following lower intensity exercises (afterburn effect).

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Running faster uses more energy and burns more calories.

/thread

bump

I did a 1:40 long run yesterday evening at a pretty good pace and had trouble getting too sleep because my body was really warm. Must have been that post workout increased metabolism.

Interesting point with the weight lifting muscle damage reference. However, wait two minutes and you can lift again though. Is the muscle repaired that quickly? Going along with the weight line of thinking, but in a different direction, Straining to bench press 200 lbs 7 times versus bench pressing 100 lbs easily 14 times, the same calorie burn? IDK.

I know the research commonly states that calorie burn per mile is the same regardless of speed. At the risk of sounding like a global warming denier who concocts all sorts of reasons why the scientists are wrong, I think what the conventional wisdom about speed being irrelevant to calorie burn per distance is generally correct. Ok if you compare running a mile at 8 mm versus 9 minute mile pace it probably doesn 't make much difference.

I feel though as one significantly increases intensity toward maximum speed and full effort energy inefficiency increases along with calorie expenditure per unit of distance.

I can not believe that full maximum effort is as energy efficient as a regular easier run and therefore burns the same calories per distance.

Maximum effort is not as efficient. Type II muscle fibers use more ATP per unit force production than do type I fibers.

Power athletes don't have to worry about energy efficiency because they don't need to sustain contractions - so they can blow through ATP for the few seconds they're active, then recover.

When measuring total energy used there was a study done on horses

This found there was an optimum pace that used the least calories. It was a steady pace but not the slowest pace which might have been anticipated

Fast pace uses the most energy

Slowest pace uses considerably less

But there is an optimum pace inbetween the two where the least energy is used. This ties in with experience of running where running really slow can feel harder than at a still relaxed but faster pace.

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Runningnonsense2004 wrote:

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Runningart2004 wrote:

There is a simple mathematical formula that calculates calories burned. Google it.

Key points:

1. Walking burns less per mile than running.
2. Running burns approximately the same per mile regardless of speed (10 cal difference per mile at 1:00 faster pace).
3. Calories burned over a 24 hour period following higher intensity exercises exceeds calories burned over a 24 hour period following lower intensity exercises (afterburn effect).

So....if your goal is weight loss then focus on higher intensity exercises (sprints, intervals, weight training) alternating with lower intensity lower impact exercises.

Alan

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Key points OK. Conclusion utterly wrong.

You can run a few miles at high intensity and you will expend a few calories more than if you run them at an easy pace. But you can run way more miles at an easy pace than at high intensity. There's simply no comparison. A few percent extra calories expended can be offset 10-fold by running further at an easy pace.

So....if your goal is weight loss then focus on high mileage.

And that's what pretty much every good runner would know from experience.

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American educational system at its best on this thread. Amazing.