Abstract
The use of aero style handlebars has gained popularity in triathlons and individual
time trial events recently. The effect of using these handlebars has only been examined
during short term exercise. It was the aim of this investigation to compare time to
exhaustion and selected measures of ventilation, gas exchange and pulmonary function
when using aero style handlebars versus standard racing style handlebars during long
term exercise. Eleven well trained cyclists with a V̇O2max of 61.7±2.9ml·kg-1·min-1 completed two continuous rides at 80 to 95 percent of their V̇O2max. Subjects rode at 80% of their V̇O2max for one hour and the work rate was increased by 5% of their V̇O2max every 15 min thereafter. The rides were completed with the subject riding his/her
personal bicycle on a Velodyne trainer and differed in that during one ride the subjects
rode with aero style handlebars and during the other they rode with standard racing
style handlebars. During the ride with standard racing style handlebars, subjects
rode with their hands on top of the bars or on the hoods of the brake levers. The
subjects rode with the standard racing handlebars for 69.3±5.3 minutes as compared
to 59.8±7.0 minutes with the aero style handlebars. This difference was not statistically
significant. The average work rates when the cyclists terminated the exercise bouts
with the aero and standard racing handlebars were 268.1 ±38.4 and 276.4±39.3 watts
and were not significant from one another. Gas exchange and ventilatory parameters
were measured every 15 mm during the exercise bouts. Oxygen consumption and minute
ventilation during the first hour were similar between the aero and standard rides,
47.6±0.9 vs 48.3±0.9 ml·kg-1·min-1 and 99.7±7.4 vs 93.9±5.81·min-1, respectively. In addition, tidal volume breathing frequency and the time components
of the breathing period, inspiratory and expiratory time, were similar between the
two rides. Pulmonary function tests were made prior to the start of exercise and one
to two mm following the completion of the exercise bout. Maximal voluntary ventilation,
forced expiratory volume in one second expressed as a percent of the forced vital
capacity and forced vital capacity were not significantly different in the standard
riding position as compared to the aero riding position. In addition, lung volumes
and total lung capacity. measured prior to the start of the exercise bout, were similar
when comparing subjects in the two riding positions. These results suggest that there
are not ventilatory or pulmonary limitations as a result of riding with aero style
handlebars. While mean differences in riding time were not statistically significant,
individual subjects did show large differences in riding times. These appear to be
related to whether or not the subjects had previously trained with aero style handlebars.
Based on this observation, it is suggested that individuals who chose to race with
aero style handlebars should also train with them.
Key words
Endurance exercise - minute ventilation - pulmonary function - lung volumes - bicycling