Uphill Running Economy: The Impact of Positive Incline on Submaximal VO2 and Running Speed

The purpose of the present study was to investigate the effect of a positive incline on submaximal oxygen consumption (VO2) and running speed compared to level running. Fifteen moderately trained trail runners underwent anthropometric, VO2 max, and running economy (RE) measurements in two laboratory sessions. RE was expressed as the net VO2 per 1% incline increase for each incline and velocity used [VO2 1% incline = (VO2 incline - VO2 level) / % incline]. The effect of 1% incline on running velocity was estimated as velocity decrement (VD) per 1% incline (VD 1% incline) = (VO2 1% incline / VO2 1 km·h-1 ). The mean value of VO2 1% incline at constant velocity was not different. In contrast, at a constant incline VO2 1% incline was significantly different depending on the running velocity. The results were the same for VD 1% incline. We concluded that for the evaluation of uphill RE a protocol of any given incline and 2 to 3 velocities can be used, with a resulting metabolic load less than 80% VO2 max. Furthermore, the estimation of VD 1% incline is a useful tool for estimating pacing during the level up parts of a trail race.