Laboratory predictors of uphill cycling performance in trained cyclists

Abstract

This study aimed to assess the relationship between an uphill time-trial (TT) performance and both aerobic and anaerobic parameters obtained from laboratory tests. Fifteen cyclists performed a Wingate anaerobic test, a graded exercise test (GXT) and a field-based 20-min TT with 2.7% mean gradient. After a 5-week non-supervised training period, 10 of them performed a second TT for analysis of pacing reproducibility. Stepwise multiple regressions demonstrated that 91% of TT mean power output variation (W kg) could be explained by peak oxygen uptake (ml kgmin) and the respiratory compensation point (W kg), with standardised beta coefficients of 0.64 and 0.39, respectively. The agreement between mean power output and power at respiratory compensation point showed a bias ± random error of 16.2 ± 51.8 W or 5.7 ± 19.7%. One-way repeated-measures analysis of variance revealed a significant effect of the time interval (123.1 ± 8.7; 97.8 ± 1.2 and 94.0 ± 7.2% of mean power output, for epochs 0-2, 2-18 and 18-20 min, respectively; P < 0.001), characterising a positive pacing profile. This study indicates that an uphill, 20-min TT-type performance is correlated to aerobic physiological GXT variables and that cyclists adopt reproducible pacing strategies when they are tested 5 weeks apart (coefficients of variation of 6.3; 1 and 4%, for 0-2, 2-18 and 18-20 min, respectively).

Power Assessment in Road Cycling: A Narrative Review

“…Similar findings have been obtained in another study, in which FTP and LT were closely linked in trained cyclists but not in recreational cyclists [24]. The PO obtained from FTP 20-min testing does not seem to correlate with all the other LT methods [24,26,27], except for fixed blood lactate concentrations of 4.0 mmol/L (r = 0.88, p < 0.001) [46]. On the other hand, another FTP testing duration has been attempted in several scientific studies.…”

“…These relationships have been previously tested and the correlations were nearly perfect for both RCP (r = 0.97) and MLSS (r = 0.91), although the intensity at which MLSS was represented differed by as much as 7% from FTP [44]. Furthermore, the relationship changed depending on the cyclists' level, with the well-trained group showing a higher association (r = 0.94) than the trained group (r = 0.91) [28,45,46]. Similar findings have been obtained in another study, in which FTP and LT were closely linked in trained cyclists but not in recreational cyclists [24].…”

A Field-Based Cycling Test to Assess Predictors of Endurance Performance and Establishing Training Zones

“…However, a field-based time trial of 4-min has also been shown to relate very strongly to two lactate turn points based on a first and second nonlinear increase in lactate versus power output (r = 0.87, 0.90) and the ventilatory threshold (r = 0.77) and respiratory compensation point (r = 0.78) (30). Similar relationships are observed for a 20min time trial in the field, performed either uphill or on flat or slightly undulating roads (11,30). Nevertheless, based on strong relationships observed between endurance performance determinants in this study and previous research, short all-out time trials (e.g.…”

“…The availability of mobile power meters has enabled cyclists to track power output along with heart rate continuously in the field during training and competition. Furthermore, given the intrusiveness of laboratory testing on the cyclist's training or competition program, more and more research is focusing on testing the validity of field-based tests to track and monitor performance changes (11,24,30,33). A field-based test provides coaches with an easy-to-implement tool to track and monitor changes in performance during different training phases.…”

Functional Threshold Power in Cyclists: Validity of the Concept and Physiological Responses

“…The obtained value might not necessarily represent the boundary between the heavy-and the severe-intensity domain [13,18], but this test is more practical than a 60-min TT and does not involve the burden of multiple MLSS assessments. Although this approach does not solve the issue of training-zone systems that do not directly compare [26], 20-min TT performance is reliable [24] and sensitive to training adaptations [22] and cycling ability [6]. To account for interindividual differences in endurance, TTEs could then be applied as indoor training sessions to establish the ideal volume of exercise targeting each intensity zone [18].…”