This study examined the effects of three testing protocols on the frequency of achievement of V̇O2max criteria in 13 male adolescent long-distance runners. All subjects completed the modified Taylor (T), Bruce (B), and Taylor intermittent (TI) running protocols on a treadmill to volitional fatigue. The criteria for V̇O2max were (a) respiratory exchange ratio (R) > 1.0, (b) heart rate (HR) >95% predicted max, and (c) increase in V̇O2 < 2.1 ml·kg−1·min−1 with an increase in workload. A plateau was identified in 54%, 39%, and 85% of the subjects during the T, B, and TI protocols, respectively (p < .05). V̇O2 at exhaustion was similar during all protocols (T = 70.8 ± 4.1, B = 71.4 ± 3.5, TI = 69.6 ± 5.0 ml·kg−1-min−1; p > .05). The data suggest that the characteristics of a protocol can determine the frequency of a plateau achievement but have no effect on the attainment of the R or HR criteria. V̇O2 during running exercise to volitional fatigue is independent of testing protocol.
Anita M. Rivera-Brown, Miguel A. Rivera, and Walter R. Frontera are with the Center for Sports Health and Exercise Sciences, Albergue Olimpico, P.O. Box 2004, Salinas, PR 00751.