Matteo Picchio (Marche Polytechnic University)
Mattia Filomena
We study the effect of ambient temperature on worker injury incidence using data from professional football (soccer) in the Italian Serie A. Identification of the causal effect relies on exogenous short-run, within-team-season variation in kick-off temperature. We document substantial heterogeneity between intrinsic and extrinsic injuries. A one-degree increase in temperature raises the number of intrinsic injuries by 1.9%, with larger effects for severe injuries (+3.9%), while extrinsic injuries are not significantly affected, suggesting that heat operates primarily through internal physiological stress. The temperature gradient is stronger in matches played at home and in the latter part of the season. Moreover, temperature differentially affects injury risk across playing positions, with midfielders, who face the highest physical demands in terms of distance covered, being the most affected. Finally, exposure to sustained high temperatures in the days prior to the match appears to attenuate the temperature effect, pointing to the relevance of short-term adaptation mechanisms rather than cumulative physiological stress.