Efficiency and Calorie Burn

[BirdMan]

As a triathlete and someone generally interested in physical culture, I often wander about caloric expenditure during various activities. I have a few questions:

With any given aerobic task (i.e. running, cycling, swimming), do athletes burn more or less calories over time as they become practiced in the movement?
-This can be framed in several different ways. For a given distance, the well-trained athlete might complete the task faster with the same level of RPE. Would they burn less calories? Is this equated if the time of exercise is equal; for example, does one hour of running burn the same amount of energy in an "runner" and a "new runner"?

Any thoughts will be appreciated!

-Bird

[JoshA]

The short answer is yes, individuals who are more trained at any given activity will perform it more efficiently (in running that would be less oxygen use and lower caloric expenditure for a given speed and distance) than those who are substantially less trained. To what degree this actually changes caloric expenditure I cannot tell you but on an individual level, I would expect it is rather insignificant as it should track with level of training and therefore change at a rather slow rate.

For more information you can look into the research regarding "running economy"
https://www.ncbi.nlm.nih.gov/pmc/art..._Article_7.pdf

[philibusters]

As you get better doing the exact same activity would burn less calories. Lets say your easy pace in running is 8 mins a mile when you start. You run 7 miles in 56 minutes. A year later your easy pace is 7 minutes a mile. Running 7 miles would only take you 49 minutes and you'd probably burn less calories than when you ran 7 miles as a beginner. That said if you ran 56 minutes easy, you'd now run 8 miles rather than 7 miles and could potentially burn more calories.

Likewise in lifting. When you start out, you do sets of 8 at RPE 8 on the bench which is 135 pounds. A year later, a set of 8 on the bench at RPE 8 may be 205 pounds. I think you'd burn less calories a year later doing a set of 135 on the bench, but perhaps you are burning just as much or more benching 205 at RPE 8 as you did benching 135 at RPE.

I assume the person in both my examples above is burning more calories a year later at RPE 8 and running 56 minutes. In the lifting example, they are using bigger muscles which should burn more calories. In the running example, they are consuming more oxygen allowing them to do more work, but I don't know that for sure.