Treadmills - a study shows they burn more calories

A study compared the energy expenditure of different exercise machines using the rating of perceived exertion (RPE) scale.

The study subjects were 13 healthy adults. During a habituation period, the subjects were familiarized with the RPE scale and exercise equipment: a cycle machine that included arm movement, a simulated cross-country skier, a cycle ergometer, a rowing ergometer, a stair climber, and a treadmill.

After habituation, subjects were tested on each machine. Each subject spent 5 minutes exercising at each of three stages of self selected intensity corresponding to RPE levels of 11 (fairly light), 13 ( somewhat hard), and 15 (hard). Measurements were taken for expired gases, hearth rates, and blood lactate concentration; VO2max and energy expenditure were calculated.

The treadmill produced significantly higher rates of energy expenditure compared with all other machines at RPE levels of 13 and 15 and compared with cycle machines with arm movement and cycle ergometers at RPE's of 11.

This study showed that running on a treadmill burned more calories for a given RPE as compared with other personal exercise equipment. Although one type of exercise is statistically higher in calorie expenditure, all six burned increasing calories with increasing exertion and were very close in energy expenditure from a practical standpoint.

Zeni AI, Hoffman MD, Clifford PS: Energy expenditure with indoor exercise machines. JAMA 1996;275(18):1424-1427