Resembling Overground and Treadmill Running Biomechanics in Female Endurance Runners by Equaling Stride Frequency Patterns

Biomechanical differences between overground and treadmill (TM) running have been described in literature. However, there are no previous studies which analyze strategies for equaling these biomechanical differences between running surfaces. This study analyzed the strategy of equaling the stride frequencies between surfaces in a group of 16 female well-trained endurance runners, who performed both overground and TM running at speeds between 9 and 21 km/hr. These runners performed TM running at the same speeds in which they were able to adapt their stride frequencies to those performed overground. Thus, only 9–15 km/hr were then analyzed in this study. The first result was that female runners showed significant differences in stride frequency, stride length, vertical displacement and mediolateral displacement between surfaces running at 9.3 and 15.1 km/hr (moderate effect sizes). The second and main result was that by equaling the stride frequencies from overground to TM running, these significant differences disappeared (trivial to small effect sizes). Besides, no differences were found between surfaces in biomechanical variables related to running cost, either before or after the stride frequency manipulation (trivial to small effect sizes). When needed, female endurance runners of the level recruited can resemble their running biomechanics between surfaces simply by means of performing the same stride frequency in both surfaces, without changes in the studied biomechanical variables related to running cost.