Hunt KJ; Anandakumaran P; Loretz JA; Saengsuwan J;
Clinical Physiology And Functional Imaging [Clin Physiol Funct Imaging] 2018 Jan; Vol. 38 (1), pp. 108-117.
Purpose: Self-paced maximal testing methods may be able to exploit central mediation of function-limiting fatigue and therefore have potential to generate more valid estimates of peak oxygen uptake. The aim of this study was to investigate the feasibility of a new method for self-paced peak performance testing on treadmills and to compare peak and submaximal performance outcomes with those obtained using a non-self-paced (‘computer-paced’) method employing predetermined speed and slope profiles.
Methods: The proposed self-paced method is based upon automatic subject positioning using feedback control together with an exercise intensity which is driven by a predetermined, individualized work-rate ramp.
Results: Peak oxygen uptake was not significantly different for the computer-paced (CP) versus self-paced (SP) protocols: 4·38 ± 0·48 versus 4·34 ± 0·46 ml min-1 , P = 0·42. Likewise, there were no significant differences in the other peak and submaximal cardiopulmonary parameters, viz. peak heart rate, peak respiratory exchange ratio and the first and second ventilatory thresholds. Ramp duration for CP was longer than for SP: 494·5 ± 71·1 versus 371·3 ± 86·0 s, P = 0·00072. Concomitantly, the peak rate of work done against gravity was higher for CP: 264·8 ± 40·8 versus 203·8 ± 53·4 W, P = 0·0021.
Conclusions: The self-paced approach was found to be feasible for estimation of the principal performance outcomes: the method was technically implementable, it was acceptable to the subjects and it showed good responsiveness. Further investigation of the self-paced method, with adjustment of the target ramp-phase duration or modification of the work-rate calculation equations, is warranted.