Comparing cycling world hour records, 1967-1996: modeling with empirical data

Purpose: The world hour record in cycling has increased dramatically in rec ent years. The present study was designed to compare the performances of fo rmer/current record holders, after adjusting for differences in aerodynamic equipment and altitude. Additionally, we sought to determine the ideal ele vation for future hour record attempts. Methods: The first step was constru cting a mathematical model to predict power requirements of track cycling. The model was based on empirical data from wind-tunnel tests, the relations hip of body size to frontal surface area, and field power measurements usin g a crank dynamometer (SRM). The model agreed reasonably well with actual m easurements of power output on elite cyclists. Subsequently, the effects of altitude on maximal aerobic power were estimated from published research s tudies of elite athletes. This information was combined with the power requ irement equation to predict what each cyclist's power output would have bee n at sea level. This allowed us to estimate the distance that each rider co uld have covered using state-of-the-art equipment at sea level. According t o these calculations, when racing under equivalent conditions, Rominger wou ld be first, Boardman second, Merckx third, and Indurain fourth. In additio n, about 60% of the increase in hour record distances since Bracke's record (1967) have come from advances in technology and 40% from physiological im provements. Results and Conclusions: To break the current world hour record , field measurements and the model indicate that a cyclist would have to de liver over 440 W for 1 h at sea level, or correspondingly less at altitude. The optimal elevation for future hour record attempts is predicted to be a bout 2500 m for acclimatized riders and 2000 m for unacclimatized riders.