The hour record is one of cycling's most prestigious events, and has been contested since 1876 when F.L. Dodds of England, riding a high-wheeled bicycle, became the first record holder, completing 26.508 km. The invention of the diamond-frame racing bicycle in 1888 led to Laurie setting a new record of 33.913 km, and this mark has steadily improved over the years, up until Francesco Moser's world mark of 51.151 in 1984. However, since that record was set, there has been a big improvement, especially in the ‘90s, with Indurain, Rominger, Obree and Boardman all setting new marks. Until 1986, all cyclists used the traditional crouch position on a standard-track racing bicycle, but the most recent record performances have involved new bicycle technology and new racing positions that dramatically reduce aerodynamic drag. To make matters more confusing, all the recent record holders have used different technology - Graeme Obree invented his own bicycle position, Rominger and Indurain used the standard aero bars, and Boardman championed the 'Superman' handlebar position. He currently holds the record with 56.375 km.

The question is: how much of these recent improvements are due to better technology and how much to improved performance by the cyclists? In an attempt to answer this question, Bassett et al (1999, Medicine & Science in Sports & Exercise, 31 (11), pp 1665-1676) designed a theoretical model to calculate the power output of the cyclists that accounted for all the major variables. These variables included velocity, altitude, equipment, clothing, body position, height, weight, track circumference and track surface. The aim of the study was to analyse each world-record performance since Bracke in 1967 and calculate the power output of each cyclist as if they had been using the same equipment at sea level. From this, the researchers could discover who produced the best performance, and how much of the recent improvements were due to technology.

What affects drag?

Bassett et al studied elite cyclists performing on a track and they directly measured their power output, using a crank dynamometer, at various speeds. From these results they formed a velocity power equation, which can predict power output (in Watts) for a given speed (in kph) of indoor track cycling. They took this basic equation and factored in variables such as tyre resistance, bearing resistance, track friction, as well as the most important variable of all, aerodynamic drag.

Aerodynamic drag is influenced by several factors. One is the air density, with lighter air requiring less power, so there is an advantage in cycling at altitude. For example, in Mexico City, where many records were set in the ‘70s and ‘80s, the air density is around 20% less than at sea level, and even though VO2max is reduced at altitude, this still constitutes a 1.7 kph advantage. The bicycle technology and cycling position used by the cyclist are also very significant for drag. For instance, the new solid disk wheels and aero handle bars make an enormous difference, as shown by data taken from testing done with Chris Boardman. Comparing cycling at 52.27 kph using a standard aero position on a modern bike with cycling at the same speed using the crouch position on a traditional bike resulted in 18% less drag for the first. Bassett and his team used wind-tunnel data of aerodynamic drag for the different bicycles and different positions used by recent record holders to establish co-efficients to compare the different conditions. The frontal area of the cyclists was also included in this positional factor.

With all these factors taken into account, Bassett and the team formulated a complex mathematical equation to calculate the actual power of each record cyclist's performance. This actual power score was then converted to sea-level power for those who had set records at altitude. This is because the max power at 2338 m is lessened because of reduced oxygen availability. The sea-level power for all record holders is the true comparison of cycling performance. This result was put into the Boardman equation to estimate the distance that would have been achieved if all cyclists had used Boardman's equipment at sea level. The findings are shown in the table.

Rominger reigns supreme

The findings are very interesting. From Bracke (1967) to Indurain (1994), all the performances are comparable, in the 52-54 km range when adjusted to Boardman's equipment for the sea-level power of the cyclists. Thus, if cyclists such as Bracke, Moser and Merckx were to attempt the hour record on a modern bike, they would achieve similar distances to Indurain, Obree and Boardman (1993). This shows that the older records were very good performances, especially from Merckx, and that the distance improvement from Bracke to Indurain was almost all technological. This technological advantage is highlighted most by Obree, since his power output is the second lowest of the eight record holders.

The most recent Rominger (1994) and Boardman (1996) records show a performance improvement, with Boardman's power output measured at 442W and Rominger's estimated at 460W. These two records are significantly superior performances compared to the other records, which means that Boardman and Rominger had improved their stamina and fitness and not just their technology.

Bassett et al concluded that the improvement in the cycling hour record seen in the last decade, compared to the ‘70s and ‘80s records achieved with traditional bicycles and racing positions, is 60% due to technology and 40% due to improved performance. The best hour cycle performance so far has been Rominger's effort in Bordeaux in 1994 where he produced a power output of around 460 W. This is approximately equivalent to a VO2 of 5.6 L/min, which is a massive aerobic capacity to cycle at for an hour and illustrates the amazing fitness levels these top cyclists achieve.

Raphael Brandon