Performance level and cardiopulmonary responses during a cycle-run trial

To determine the effect of triathlete performance level on the cardiorespir atory responses elicited by the cycle-run succession, eight regionally and nationally-ranked (Competitive) and five internationally-ranked (Elite) mal e triathletes underwent four successive laboratory trials: 1) an incrementa l treadmill test, 2) an incremental cycle test, 3) 30 min of cycling follow ed by 20 min of running (C-R), and 4) a 20-min control run (R) at the same speed as the run in C-R. Before and 10 min after the third and fourth trial s the triathletes underwent lung function testing: spirometry and diffusing capacity testing for carbon monoxide (DLCO). During the C-R trial blood sa mples were drawn to measure venous lactate concentration. During all trials ventilatory data were collected every minute using an automated breath-by- breath system. The results showed that 1) the oxygen uptake ((V)over dot O- 2,) of post-cycling running verses running alone was similar for both group s; 2) the ventilatory responses ((V)over dot (E) (V)over dot (E)/(V)over do t O-2,O- (V)over dot (E)/(V)over dot CO2 and f) of C-R running versus R wer e significantly higher (P < 0.005) for the Competitive group: and 3) a sign ificant decrease (P < 0.05) in DLCO was also noted after the C-R trial in t he Competitive group but not in the Elite group. We concluded that 1)the ve ntilatory responses during a run subsequent to cycling may be related to th e triathlete performance level, and 2) the C-R trial induced specific alter ations in pulmonary function that may be associated with respiratory muscle alteration and exercise-induced hypoxemia in the Competitive triathletes.