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.