The Benefits Of Elliptical Training
There is no exact cross-training substitute for running, but elliptical training can provide similar fitness benefits for injured runners or those that need to cross-train to supplement mileage. While direct comparisons between elliptical training and running are limited in scientific research, I did uncover some data about how elliptical training and running compare.
In one study, researchers compared oxygen consumption, energy expenditure, and heart rate on a treadmill versus an elliptical when exercising at the same perceived level of exertion. The results indicated that while heart rate was slightly higher on the elliptical, oxygen consumption and energy expenditure were similar on both machines. As such, the researchers concluded that “during a cross training or noncompetition-specific training phase, an elliptical device is an acceptable alternative to a treadmill.”
A 2004 study reviewed the apparent differences in heart rate on the treadmill compared to the elliptical machine. While the researchers did not find the same elevated heart rate levels seen in the previously mentioned study, they did find that the rating of perceived exertion (RPE) was the same in the chest and actually more intense for the legs on the elliptical compared to the treadmill (presumably from the incline). As such, the researchers concluded that using RPE as a measurement of effort can produce fitness results similar to running.
Finally, another study compared metabolic and cardio-respiratory improvements following a 12-week training program using an elliptical trainer versus a treadmill. The researchers found that when training volumes and intensities were equivalent on the treadmill and elliptical, physiological adaptations remained relatively the same.
The results of these limited studies suggests that while the elliptical is not a perfect substitution for running, it will allow you to maintain some level of fitness during time off from training.
The only potential drawback to the elliptical machine for injured runners is that it can still aggravate some injuries, despite the lack of impact. Those injuries include stress fractures, achilles injuries, and IT band issues. So, be careful and listen to your body when on the elliptical.