Elevation gain in running refers to the total amount of vertical height climbed during a run, measured in meters or feet. It is the change in altitude over the course of the run, and it can be positive or negative depending on whether the runner is above or below their starting altitude. Elevation gain is an important factor to consider when training for trail running or races with significant elevation changes. The amount of elevation gain in a run can vary widely depending on the terrain and location. For example, a flat run has 0-10 feet of gain per mile, while a mountainous run can have 250+ feet of gain per mile. In general, a moderately rolling run has 10-50 feet of gain per mile, and a rolling run has 50-150 feet of gain per mile. The elevation gain for a race can be found in the races elevation profile, which shows where the course climbs up and when it comes back down.