Supramaximal verification of peak oxygen uptake in adolescents with cystic fibrosis

To study whether peak oxygen uptake ((Equation is included in full-text article VO₂ peak), attained in traditional cardiopulmonary exercise testing (CPET) in adolescents with cystic fibrosis (CF), could be verified by a supramaximal exercise test. Sixteen adolescents with CF (forced expiratory volume in 1 second as % of predicted [range, 45%-117%]) volunteered and successively performed CPET and a supramaximal test (Steep Ramp Test [SRT] protocol). Cardiopulmonary exercise testing and the SRT resulted in comparable cardiorespiratory peak values. We found no significant difference in oxygen uptake ((Equation is included in full-text article VO₂ peak/kg) between CPET and the SRT (38.9 ± 7.4 and 38.8 ± 8.5 mL min kg, respectively; P = .81). We found no systemic bias for CPET and SRT measurements of (Equation is included in full-text article VO₂ peak/kg and no differences between CPET and SRT (Equation is included in full-text article VO₂ peak values within and between the maximal and non-maximal effort groups (P > .4). The (Equation is included in full-text article VO₂ peak measured in CPET seems to reflect the true (Equation is included in full-text article.)O2 peak in adolescents with CF.