Two years ago, we heard about a study which indicated that even though e-bikes require less rider effort to travel at a given speed, they're still a decent source of exercise. Now, a new study suggests that they're just as good as regular bikes at improving fitness – at least when it comes to overweight riders.

Conducted by scientists at Switzerland's University of Basel, the study involved 32 test subjects. Twenty-eight of them were men, and all were considered to be overweight, having a body mass index between 28 and 29. At the outset of the study, each person's cardiorespiratory fitness was determined via oxygen uptake capacity (VO2) testing, which measures the body's ability to take in and utilize oxygen.

Seventeen of the participants were then supplied with an e-bike, with the other 15 receiving a regular non-electric bike. All of them were instructed to ride a minimum of 6 km (3.7 miles) at least three days per week for a four-week period. Some riders were equipped with GPS devices, and all of them cycled at a speed of their choice.

When the four weeks were up, new VO2 tests indicated the fitness levels of both groups had improved significantly, and by similar amounts. Riders in the e-bike group, however, maintained a higher average speed, and rode up steeper gradients on a daily basis.

"This indicates that the e-bike can increase motivation and help overweight and older individuals to maintain fitness training on a regular basis," says U Basel's Prof. Arno Schmidt-Trucksäss. "Those who use e-bikes on a regular basis benefit permanently, not only in terms of their fitness, but also in terms of other factors such as blood pressure, fat metabolism, and their mental well-being."

A paper on the research was recently published in the Clinical Journal of Sport Medicine.