Characterizing intensity of E-biking in the context of the exercise intensity domains framework

Purpose

E-bikes are promoted as an active mode of transportation which can aid with meeting current physical activity recommendations. For the first time, this study evaluated exertional intensity associated with commuting with an E-bike within the framework of the exercise intensity domains. We hypothesized that the reduction in exertional intensity when using an E-bike for commuting is such that the resulting metabolic demand will be substantially lower than that suggested to improve cardiorespiratory fitness.

Methods

Forty-four participants (22 females) of varying fitness levels completed two experimental sessions. The first session involved a lab-based ramp-incremental exercise test to determine VO_2max, gas exchange threshold (GET), and respiratory compensation point (RCP). The second session involved the completion of two outdoor rides on the same bike equipped with an electrical motor. The first ride was completed without electrical assistance while for the second ride the assistance was kept activated throughout.

Results

With the electrical assistance the power output (PO) of commuting was reduced by 87 ± 19 W compared to without electrical assistance. Such reduction in PO lowered the metabolic demand of cycling by approximately 69 % which fell approximately 34 % below GET. While the absolute reduction in PO was different between males and females, when normalizing it for the individual GET, there were no differences between sexes.

Conclusion

Despite E-bikes facilitate a more active lifestyle while helping to reduce the emission of air pollutants, when interpreted within the context of the exercise intensity domain framework, the corresponding exertional intensity is likely insufficient to elicit cardiorespiratory benefits.