Reliability of Time to Exhaustion Above the Power Output at VO2peak in Trained Mountain Bikers

• Published in: International journal of exercise science Vol. 16; no. 4; pp. 654 - 664
• Main Authors: Inoue, Allan, Lattari, Eduardo, Carmo, Everton C, Oliveira, Bruno R R, Silva, Elirez B, Santos, Tony M
• Format: Journal Article
• Language: English
• Published: Berkeley Electronic Press 01-01-2023
• Subjects: Original Research
• ISSN: 1939-795X; 1939-795X
• DOI: 10.70252/NBYJ5810

To our knowledge, no study has investigated the reliability of the time to exhaustion (TTE) test during constant-load trials in Olympic distance cross-country mountain bike (XCO-MTB) athletes. Thus, the aim was to analyze the reliability of the TTE test at intensities above peak oxygen uptake (VO
2peak
) in trained XCO-MTB athletes. Fifteen male XCO-MTB athletes (mean ± SD: age 31.5 ± 6.6 years, stature 174.0 ± 5.4 cm, body mass 67.2 ± 5.1 kg, VO
2peak
64.5 ± 4.7 mL·kg
−1
·min
−1
) completed 2 TTE tests on the cycle ergometer with 4 different intensities above the maximal work rate in the incremental test (W
max
) (105%, 120%, 130%, and 140% of W
max
). There was moderate reliability between TTE tests at 105% (intraclass correlation coefficient (ICC) = 0.81,
p
≤ 0.001; coefficient of variation (CV) = 9.1%; standard error of measurement (SEM) = 18.3%), and 120% (ICC = 0.88,
p
≤ 0.001; CV = 6.6%; SEM = 9.3%) W
max
. For intensities of 130% (ICC = 0.53,
p
= 0.018; CV = 9.2%; SEM = 15.8%) and 140% (ICC = 0.56,
p
= 0.012; CV = 12.2%; SEM = 13.5%) W
max
, the reliability results proved to be questionable. In addition, no significant differences were found between the 2 TTE tests in all intensities (
p
> 0.05). Caution should be taken when assessing TTE above VO
2peak
or when using it as a performance indicator, given its moderate to questionable reliability.