Impact of elbow stiffness on running economy in trained athletes.

Background: Elbow injuries are likely to generate a decreased range of motion (ROM), which might negatively affect athletic performance. To date, the effect of elbow stiffness on endurance running performance has never been studied. We conducted an observational, prospective, cross-over study to examine the impact of elbow stiffness on running economy.

Methods: Twenty trained athletes performed running economy tests at 12 km·h^-1, with and without a limited elbow ROM (flexion: 90°, extension: 45°), imposed by a dynamic brace mimicking a severe elbow stiffness. Relative intensity and performance indexes were measured during a subsequent maximal incremental exercise test.

Results: Running economy was measured at 180 ± 10.6 mlO₂·km^-1·kg^-1 with a full ROM, and 180.2 ± 12.3 mlO₂·km^-1·kg^-1 with the limited ROM showing a non-significant 0.1% difference (p = 0.871).

Discussion: Athletes experiencing post-traumatic elbow stiffness can find reassurance in knowing that it does not seem to impact a crucial metric of endurance running performance, namely running economy. Further research could explore elbow movement at different intensities of running, from higher aerobic speeds to sprinting.