RT Journal Article SR Electronic T1 Predicting peak cycle work rate from the incremental shuttle walk test in COPD JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP p2990 VO 38 IS Suppl 55 A1 Rahizan Zainuldin A1 Martin Mackey A1 Nia Luxton A1 Jennifer Alison YR 2011 UL http://erj.ersjournals.com/content/38/Suppl_55/p2990.abstract AB Equations predicting peak work rate (Wpeak) on an incremental cycle test (ICT) from an incremental shuttle walk test (ISWT) have been developed but often overestimate Wpeak. Since peak oxygen consumption (VO2) from the ISWT and ICT have been shown to be equivalent in moderate to severe COPD, it may be possible to use VO2 as the common measure between ISWT and ICT to improve the accuracy of the predictive equations. The study aimed to develop equations to estimate the Wpeak of an ICT from an ISWT using VO2 as the common link. In a prospective study 45 participants with COPD (mean [SD] FEV1 = 57 [18]%predicted) performed an ICT and two ISWTs. Data from the better ISWT were used for analysis. Gas exchange during exercise tests was measured by a portable gas analyser. The analyses performed were: 1) Stepwise multiple regression analysis with independent variables of gender, age, height, FEV1 and ISWwork (product of ISWdistance and weight) used to develop an equation predicting peak VO2 (VO2peak(ICT)); 2) The slopes and intercepts of the relationship between VO2(ICT) and work rate for each participant were averaged to create an equation relating VO2(ICT) and work rate. The mean peak VO2 measured in the ISWT and ICT were not significantly different. From the stepwise analysis, the regression equation was VO2peak(ICT) = 0.016$*$ISWwork + 9.28$*$Ht – 831.6 (r=0.79). A linear relationship between VO2(ICT) and work rate was found, thus an equation to predict peak work rate was developed as: Wpeak = (VO2peak(ICT) – 425)/10.3. The calculation of a Wpeak(ICT) from a clinically available ISWT via these equations may aid prescription of cycle training intensity when an ICT is unavailable.