Which activity are you better at cycling or running? 80% of your maximum heart rate may be at a lower exercise intensity from one activity to another.
It is possible that you would burn more calories from one activity to another because you are better at it and can work at a higher intensity.
I so wish for you it was cut and dry, that 80% of your maximum heart rate burns X amount of calories whatever the activity, but that is not the case. You got to take skill level among other things into consideration.
Good question. Theoretically, yes, both would burn the same, given that the heart rate is the same. Heart rate increases due to an increased need to intake oxygen and excrete carbon dioxide. The need for oxygen intake and carbon dioxide out gassing, is driven by four parts of your cardiovascular system; heart, lungs, blood, and muscles. Without going into unneeded detail, depending on how each of those components are able to uptake, transport, and utilize oxygen will determine the demand placed on the heart to increase the rate of blood flow around the body. If one of those components becomes really efficient, then the demand for blood flow (oxygen) is decreased.
Lets speak about the muscles individually for a moment, as Joanne has alluded to. If you are a great cycler and poor swimmer (and hardly ever swim), then you will have a higher heart rate at the same workload for swimming than for cycling. This is due to ONE, increased movement efficiency, and/or TWO, increased oxidative capacity of the leg muscles, compared to the shoulder and arm muscles. I will note interestingly however, that cycling doesn’t show the same reduction in H.R. due to increased movement efficiency as does running for example. This is because cycling is unidirectional, performed in a single plane, and mechanically non-variant. So other than oxidative changes of the leg muscles, which primarily is the reason for a lowered H.R. response over time, there are minor movement pattern changes possible that could account for any significant H.R. drops during the same period. Swimming however, would show a significant decrease in the demand for oxygen over time, at the same workload (stroke rate), due to both oxidative changes and movement pattern changes. This occurs in swimming since individual movement patterns for that sport can vary greatly from what is mechanically optimal. Thus, improvements in movement efficiency can be greater and can more significantly impact oxygen demand, and thus H.R. over time. I hope I am saying it in a way that is not confusing.
But getting back to your question, I think there is a much larger issue that you might be overlooking. Who cares which burns more? Really, who cares? Meaning, the most important factor in helping a client decide which is the best cardiovascular exercise for them shouldn’t be based on which machine might burn more calories. In other words, if I tell a client to do machine X because it burns more calories, and they happen to hate machine X, then what I really did was tell them the worst machine to do. Thus, over time, they will do less cardio and burn less calories. However, if I asked them which machine they want to do, and they picked machine Y, then I would show them how to use that machine and possibly even ways to do it differently making it more difficult, etc. By focusing on the machine(s) that they like, I will get them to do more cardio, stick with their training program longer, and achieve more success with their fitness program and goals. Sometimes a clients personal psychology simply trumps any quantitative oxidative calculations that can be made. One caveat here, make sure the cardiovascular machine that you and your client decide on works well with their joints, and/or medical limitations, etc.
Great post Don!
It is also important to consider that the formula for determining METs for cycling doesn’t take the rider’s weight into consideration as the bike supports the rider. With cycling, as you mention in your post, we are talking about localized endurance. Running is a different ball game together it’s an unsupported activity.
Thought you might find this abstract of interest:
MOYNA, N. M., R. J. ROBERTSON, C. L. MECKES, J. A. PEOPLES, N. B. MILLICH, and P. D. THOMPSON. Intermodal comparison of energy expenditure at exercise intensities corresponding to the perceptual preference range. Med. Sci. Sports Exerc., Vol. 33, No. 8, 2001, pp. 1404-1410.
Purpose: This study compared the rate of energy expenditure among six popular exercise machines at intensities corresponding to ratings of perceived exertion (RPE) for fairly light (RPE-11), somewhat hard (RPE-13), and hard (RPE-15) in 9 healthy men and 10 healthy women.
Methods: A maximal exercise test on each exercise machine was used to anchor the Borg 15-point category scale. Subjects performed three submaximal exercise tests at selected RPEs on a treadmill, stair-stepper, cycle ergometer, rowing ergometer, cross-country ski simulator, and rider. The submaximal tests on each exercise device were performed in random order and were 6 min in duration with 15-min rest between trials. Oxygen uptake, heart rate, and blood lactate concentration were measured during the final 2 min of each exercise intensity.
Results: Energy expenditure at each RPE was highest on the treadmill and ski simulator in men, and on the treadmill, ski simulator, and rowing ergometer in women. Energy expenditure in men and women at all RPEs was lowest on the rider and cycle ergometer. Energy expenditure at a given RPE was greater in men than women on all exercise machines, but men and women used a similar percentage of their machine specific peak oxygen uptake at each RPE on all machines. Heart rate was generally similar among the machines and between both men and women at each RPE.
Conclusions: Our results indicated that there are large differences in energy expenditure between exercise machines and between men and women at intensities perceived to be fairly light, somewhat hard, and hard. Consequently, subjects can expend more calories at the same RPE during treadmill and ski simulator exercise, for example, than during exercise with other devices. This may have important implications for the health benefits of different exercises and in promoting long term exercise adherence.
No. Different muscles and different levels of training. HR is not a measure of minute caloric expenditure. Joanne’s answer is right on the mark. To Miroslava, it depends on what I am trained in. If I am a cyclist, then that is the type of exercise where I expend the most calories/minute.