Individuals facing competitive targets increase their effort but respond non-monotonically to the target’s difficulty. We use a novel dataset of informal amateur cycling competitions to track the responses of individuals to competitively-set targets (in the form of displacement from the top of a leaderboard). Modeling the choice problem of these individuals, we derive a set of testable hypotheses. We find, as predicted by the model, that individuals compete sooner and more intensely after displacement. As our main result, we find an inverted-U relationship between the increase in effort and the size of the displacement.