Friends for (almost) a day: Studying breakaways in cycling races

We study breakaways in cycling races and examine the determinants of their success. Early on in a cycling race, a small group of riders generally slips away from the main bunch of riders and starts building a lead over this ‘peloton’, in the hopes of staying out of its hands until the finish. The slipstreaming benefits of sheltering behind another rider yield free-riding incentives to each breakaway member, turning the interaction into a social dilemma. This study is the first to empirically examine breakaway success from this perspective. To this end, we employ a self-compiled, rich data set. We find a positive effect of group size and group strength on breakaway success. The effect of group size is concave (i.e., decreasing in size) and becomes negative when the number of riders in the breakaway exceeds 26. This is in line with the opinion of cycling commentators who believe that breakaways can be both ‘too small’ and ‘too large’ to be successful. Our study contributes to the literature studying social dilemmas in the field and strategic behavior in sports.