A validation of the 10-meter incremental shuttle walk test as a measure ofaerobic power in cardiac and rheumatoid arthritis patients

Objective: To validate a simple, clinically relevant, and inexpensive test of aerobic power-the 10-meter incremental shuttle walk test (SWT)-in 2 sepa rate patient populations. Design: Two-sample validity study. Setting: Physiotherapy department of major hospital in the United Kingdom. Patients: Convenience samples of rheumatoid arthritis (RA) patients (n = 10 ) and cardiac patients (n = 10). Intervention: Subjects were attached to a portable respiratory gas analyzer to measure oxygen uptake. They walked around an oval 10-meter course, star ting at 0.5m/s, with velocity gradually increased by,17m/s increments for a s long as they could, for up to 12 minutes. Main Outcome Measures: A subject's maximal rate of oxygen uptake during exe rcise (Vo(2)max) established with linear extrapolation was regressed agains t the number of shuttles completed (distance walked). An earlier study (n = 28) showed high levels of reliability and validity with linear extrapolati on. Results: No significant linear relationship was found between Vo(2)max and the number of shuttles completed (R-2; RA subjects = 9.7%, cardiac subjects =.03%, p > .05). Conclusion: These results do not support use of the SWT as a representative measure of aerobic power. Despite this finding, the advantages of developi ng a clinically viable alternative to costly laboratory testing warrants fu rther study of the SWT in patient groups. (C) 2001 by the American Congress of Rehabilitation Medicine and the Americ an Academy of Physical Medicine and Rehabilitation.