Non-exhaustive double effort test is reliable and estimates the first ventilatory threshold intensity in running exercise.

PURPOSE

The present study aimed to investigate the reliability of the non-exhaustive double effort (NEDE) test in running exercise and its associations with the ventilatory thresholds (VT and VT) and the maximal lactate steady state (MLSS).

METHODS

Ten healthy male adults (age: 23 ± 4 years, height: 176.6 ± 6.4 cm, body mass: 76.6 ± 10.7 kg) performed 4 procedures: (1) a ramp test for VT and VT determinations measured by ratio of expired ventilation to O uptake (VE/VO) and expired ventilation to CO output (VE/VCO) equivalents, respectively; (2) the NEDE test measured by blood lactate concentration (NEDE) and heart rate responses (NEDE); (3) a retest of NEDE for reliability analysis; and (4) continuous efforts to determine the MLSS intensity. The NEDE test consisted of 4 sessions at different running intensities. Each session was characterized by double efforts at the same running velocity (E1 and E2, 180 s), separated by a passive recovery period (90 s rest). LAC and HR values after E1 and E2 (in 4 sessions) were used to estimate the intensity equivalent to "null delta" by linear fit. This parameter represents, theoretically, the intensity equivalent to maximal aerobic capacity.

RESULTS

The intraclass correlation coefficient indicated significant reliability for NEDE (0.93) and NEDE (0.79) (both <0.05). There were significant correlations, no differences, and strong agreement with the intensities predicted by NEDE (10.1 ± 1.9 km/h) and NEDE (9.8 ± 2.0 km/h) to VT (10.2 ± 1.1 km/h). In addition, despite significantly lower MLSS intensity (12.2 ± 1.2 km/h), NEDE and NEDE intensities were highly correlated with this parameter (0.90 and 0.88, respectively).

CONCLUSION

The NEDE test applied to running exercise is reliable and estimates the VT intensity. Additionally, NEDE intensities were lower but still correlated with VT and MLSS.