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.