Effect of age on 16.1-km time-trial performance

Abstract

In this study, we assessed the performance of trained senior (n = 6) and veteran (n = 6) cyclists (mean age 28 years, s = 3 and 57 years, s = 4 respectively). Each competitor completed two cycling tests, a ramped peak aerobic test and an indoor 16.1-km time-trial. The tests were performed using a Kingcycle™ ergometer with the cyclists riding their own bicycle fitted with an SRM™ powermeter. Power output, heart rate, and gas exchange variables were recorded continuously and blood lactate concentration [HLa] was assessed 3 min after the peak ramped test and at 2.5-min intervals during the time-trial. Peak values for power output (RMPmax), heart rate (HRpeak), oxygen uptake ([Vdot]O2peak), and ventilation ([Vdot] Epeak) attained during the ramped test were higher in the senior group (P < 0.05), whereas [HLa]peak, RERpeak, [Vdot] E:[Vdot]O2peak, and economypeak were similar between groups (P > 0.05). Time-trial values (mean for duration of race) for power output (WTT), heart rate (HRTT), [Vdot]O2 ([Vdot]O2TT), and [Vdot] E ([Vdot] ETT) were higher in the seniors (P < 0.05), but [HLa]TT, RERTT, [Vdot] ETT:[Vdot]O2TT, and economyTT were similar between the groups (P > 0.05). Time-trial exercise intensity, expressed as %RMPmax, %HRpeak, %[Vdot]O2peak, and %[Vdot] Epeak, was similar (P > 0.05) for seniors and veterans (WTT: 81%, s = 2 vs. 78%, s = 8; HRTT: 96%, s = 4 vs. 94%, s = 4; [Vdot]O2TT: 92%, s = 4 vs. 95%, s = 10; [Vdot] ETT: 89%, s = 8 vs. 85%, s = 8, respectively). Overall, seniors attained higher absolute values for power output, heart rate, [Vdot]O2, and [Vdot] E but not blood lactate concentration, respiratory exchange ratio (RER), [Vdot] E:[Vdot]O2, and economy. Veterans did not accommodate age-related declines in time trial performance by maintaining higher relative exercise intensity.