When exercising, does the amount of effort determine calories burned or the actual work being done?


Will an athlete who runs for an hour at moderate pace and is not tired at the end burn more calories than an out of shape person who runs for an hour a way shorter distance but is exhausted at the end?
Assuming both have the same weight and such

What I want to know basically is if your body gets stronger will it need less energy to perform the same amount of work?

In: 1708

In general no, it requires a set amount of energy (calories) to do the same amount of work. In fact, work and energy as physical quantities have the same measurement unit (it’s Joule). However, it is possible that training will make your body more efficient at doing work, so there may be less energy wasted (like on needless movements, or panting etc.) and thus less energy spent overall. But being exhausted does not necessarily mean you’ve done more work.

Being tired/out of breath is a signal that you’re operating at something approaching your limits.

Work is work though. A 200lb person jogging for 100 metres at the same pace as someone weighing 100lbs is going to use roughly twice the energy.

You burn ~30% more calories jogging than walking. But that’s about it (i.e if you increase running speed more the increase in calories burnt doesn’t increase as much).

So walking 1km burns less energy than running 1km. Obvs efficiency comes into it as you get fitter your body becomes better at stuff. For example if your leg muscles are initially weak you may be using other muscles to compensate for the weakness.

Edit: here’s a study about it

I’m not a scientist, but I have lost weight using a weight loss app that tracks calories burned. Since it knows how heavy I am, the distance I traveled, and how fast I did it, it can tell me how many calories I burned during my exercise. I noticed that at around 220 lbs, it takes about 480 calories to run 5 km in 40 minutes, opposed to around 400 calories to run it when I was at 190 lbs, running it in around 35

I may be mistaken, but it seems the question isn’t being answered?

Does a calorie represent the amount of work accomplished outside your body (like, travelling 1K), or the amount of internal work (travelling 1K easily or having to work hard)?

If a pro athlete runs 1K and an average guy runs 1K, did they both burn the same number of calories?