The purpose of our investigation was to analyse the breathing patterns of p
rofessional cyclists during incremental exercise from submaximal to maximal
intensities. A group of 11 elite amateur male road cyclists [E, mean age 2
3 (SD 2) years, peak oxygen uptake ((V)over dot O-2peak) 73.8 (SD 5.0) ml .
kg(-1) min(-1)] and 14 professional male road cyclists [P, mean age 26 (SD
2) years, ((V)over dot O-2peak) 73.2 (SD 6.6) ml . kg(-1) min(-1)] partici
pated in this study. Each of the subjects performed an exercise test on a c
ycle ergometer following a ramp protocol (exercise intensity increases of 2
5 W . min(-1)) until the subject was exhausted. For each subject, the follo
wing parameters were recorded during the tests: oxygen consumption ((V)over
dot O-2), carbon dioxide output ((V)over dot CO2). pulmonary ventilation (
(V)over dot E), tidal volume (V-T), breathing frequency (f(b)), ventilatory
equivalents for oxygen ((V)over dot (E) . (V)over dot O-2(-1)) and carbon
dioxide ((V)over dot (E) . (V)over dot CO2-1), end-tidal partial pressure o
f oxygen and partial pressure of carbon dioxide, inspiratory (t(I)) and exp
iratory (t(E)) times, inspiratory duty cycle (t(I)/t(TOT), where t(TOT) is
the time for one respiratory cycle), and mean inspiratory flow rate (V-T/t(
I)). Mean values of (V)over dot (E) were significantly higher in E at 300,
350 and 400 W (P < 0.05, P < 0.05 and P < 0.01, respectively); f(b) was als
o higher in E in most moderate-to-maximal intensities. On the other hand, V
T showed a different pattern in both groups at near-to maximal intensities,
since no plateau was observed in P. The response of t(I) and t(E) was also
different. Finally, V-T/t(I) t(I) and t(I)/t(TOT) showed a similar respons
e in both P and E. It was concluded that the breathing pattern of the two g
roups differed mainly in two aspects: in the professional cyclists, (V)over
dot (E) increased at any exercise intensity as a result of increases in bo
th V-T and f(b), with no evidence of tachypnoeic shift, and t(E) was prolon
ged in this group at high exercise intensities. In contrast, neither the ce
ntral drive nor the timing component of respiration seem to have been signi
ficantly altered by the training demands of professional cycling.