Author(s): VEGHARIASL, B., MANCHADO-GOBATTO, F.B., GOBATTO, C.A., MARCORA, S.M., BARBIERI, R.A. , Institution: BOLOGNA UNIVERSITY, Country: ITALY, Abstract-ID: 1956

INTRODUCTION:
Aerobic fitness in athletes is mainly determined by their aerobic and anaerobic thresholds. One of the most used methods for determining Aerobic fitness requires the measurement of physiological parameters, such as ventilation or blood lactate during maximum exercise, which can become a limitation in the application for all populations. A protocol with non-exhaustive double efforts (NEDE) could be a low-cost and short-duration option for all populations. The study aimed to verify the associations of NEDE with the ventilatory thresholds and investigate the reliability of NEDE for cycling.
METHODS:
Nine healthy male amateur cyclists (age: 44 ± 9 yrs, height: 178.4 ± 8.3 cm, weight: 75.6 ± 9.1 kg, VO2max: 47.25 ± 5.05 ml.kg-1.min-1) performed a protocol divided into 3 stages: (1) a incremental test for ventilatory threshold 1 (VT1) and ventilatory threshold 2 (VT2) determinations from ventilatory parameters; (2) the NEDE (NEDE 1) test measured by blood lactate concentration and (3) a retest of NEDE (NEDE 2) for reliability analysis. The NEDE test consisted of 4 sessions at different cycling intensities. Each session featured a double-effort design, consisting of two 180-second cycling at identical velocity (E1 and E2), interspersed with a 90-second passive recovery interval. The delta lactate (LAC) values recorded following both E1 and E2 efforts (delta = E2 - E1) across all four sessions were used to estimate, via linear regression, the exercise intensity corresponding to a "null delta”, which theoretically represents the intensity equivalent to maximal aerobic capacity. ANOVA variance analysis for repeated measures and Pearson test were applied, respectively, to compare and to correlate NEDE 1, NEDE 2, VT1, and VT2. Intraclass correlation verified reliability between NEDE 1 and NEDE 2. In addition, the coefficient of variation and standard error were calculated.
RESULTS:
NEDE 1 (159.9 ± 32.8 W) and 2 (162.5 ± 39.9 W) presented no differences with the VT1 (136.1± 37.8 W, p =0.142 and 0.086, respectively). Significant correlations (r = 0.724 and 0.773; p = 0.027 and 0.015, respectively), moderate coefficient of variance (11.4 % and 2.9 %) and moderate typical error (18.8 W and 18.7 W) were observed between NEDE 1 and 2 with VT1, respectively. In addition, NEDE 1 and 2 showed a significant correlation (r = 0.847 and 0.846; p = 0.004 and 0.004, respectively) with VT2 (233.3 ± 30.6 W). The intraclass correlation coefficient indicated significant reliability for NEDE 1 versus NEDE 2 (0.961, p<0.000) with a small coefficient of variance and typical error (2.9% and 7.3W).
CONCLUSION:
The non-exhaustive double effort test for cycling is valid for estimating the first ventilatory threshold and demonstrates high reliability, which could be a low-cost and short-duration protocol option for all populations.