A new reliable laboratory test of endurance performance for road cyclists

Purpose: The purpose of this study was to devise and evaluate a laboratory test of cycling performance that simulates the variable power demands of co mpetitive road racing The test is a 100-km time trial interspersed with fou r I-km and four 4-km sprints. Methods: On three occasions separated by 5-7 d, eight endurance-trained cyclists (peak oxygen uptake 5.0 +/- 0.7 L.min(- 1), peak power output 411 +/- 43 W, mean +/- SD) performed the test on thei r own bikes mounted on an air-braked Kingcycle ergometer. Subjects were fre e to regulate their power output but were asked to complete each sprint and the full distance as quickly as possible. The only feedback given to the c yclists during each test was elapsed distance. Results: In the first test, time for the 100 km and mean times for the l-km and 4-km sprints were 151:4 2 +/- 10:36, 1:16 +/- 0:06, and 5:31 +/- 0:16 min:s, respectively; these ti mes improved by 1.6-2.2% in the second test, but there was little further i mprovement in the third test (0.7 to -0.5%). The between-test correlation f or 100-km time was 0.93 (95%CI 0.79 to 0.98), and the within-cyclist coeffi cient of variation was 1.7% (95%CI 1.1 to 2.5%). Mean sprint performance sh owed similar good reliability (within-subject variation and correlations fo r the I-km and 4-km sprint times of 1.9%, 2.0%, 0.93, and 0.81, respectivel y). Conclusions: The high reliability of this laboratory test will make the test useful for research on performance of competitive road cyclists.