Prism Glasses Reduce Aerodynamic Drag in Time Trial Cycling on The Velodrome

Abstract

In the highly competitive world of cycling time trials, reducing aerodynamic drag is the most important instrument to increasing performance. This study explores the effects of using prism glasses, already used by climbers, to prevent overstraining neck muscles while securing another climber above, as a new tool to decrease aerodynamic drag in cycling time trials. The prism glasses shift a person’s vision with 45°, allowing the cyclist to keep their head tucked and pointed downwards, while still being able to see the road ahead. This study compared this downward, more ergonomic position with the glasses with an upright time trial head position in five high level cyclists on an indoor velodrome. The setup and methodology of the study was approved by the ethical commission of the University of Antwerp, allowing for the cyclists to ride on the velodrome at high speeds of 45 km/h with the glasses. The study revealed significant improvements in aerodynamic drag (CdA) for participants when wearing prism glasses while obtaining a downward head position, compared to the normal upward head position during cycling. Participants showed reductions in CdA ranging from 2.1% to 3.3% compared to normal racing position. Results were confirmed across all participants with frontal area tracking on a static indoor bike trainer (FAAST-trainer pro), where cyclists held an identical position to the one during the velodrome tests. Participants were able to comfortable use the glasses at high speeds in straight sections, however not in corners. The balance of the ride is affected by the glasses, but the learning curve proved to be steep for the participants in this study.

Keywords: Cycling Aerodynamics, Cycling Ergonomics, Cycling safety

DOI: 10.54941/ahfe1005285