There is a growing body of literature on the impact of COVID-19 on workers' performance upon recovery. This paper explores that question using granular data from professional athletes. Using a difference-in-difference estimation strategy and estimating an n-dimensional performance index, we find that performance drops upon recovery during the first thirty days after infection by 13,6%. Taking advantage of Colombia's mountainous geography, our results indicate that the main driver of performance drop in athletes is performance at high altitudes.