Cardiorespiratory fitness and functional capacity assessed by the 20-meter shuttle walking test in patients with coronary artery disease.
OBJECTIVE
To validate the 20-meter shuttle walking test (20MST) in the assessment of maximal oxygen consumption (VO(2)max) and maximal speed in patients with coronary artery disease (CAD).


METHODS
Single-sample validity study.


METHODS
Cardiac rehabilitation service in France.


METHODS
Seventeen men with CAD.


METHODS
Subjects underwent a symptom-limited treadmill test (SLTT) in a laboratory, with a speed starting at 2.5km/h and increasing by 0.5km/h every minute, and performed an adapted 20MST in a corridor, with a speed starting at 3km/h and increasing by 1km/h every minute until exhaustion.


METHODS
VO(2) measured during the 20MST with the Cosmed K2 telemetric gas analyzer (K2 VO(2)), estimated VO(2) calculated by the Léger equation (Léger VO(2)) from the maximal speed obtained during the 20MST, and VO(2) measured during the SLTT (SLTT VO(2)). Maximal speeds attained on the treadmill and on the 20MST were also compared.


RESULTS
A significant (P<.0001) difference was observed between the Léger estimate of VO(2) and those of K2 VO(2) and SLTT VO(2) (mean +/- standard deviation, 12.28+/-5.90mL. min(-1).kg(-1) vs 23.04+/-7.17 and 22.56+/-6.29mL.min(-1).kg(-1)). No difference was found between the treadmill and the 20MST maximal speeds (6.73+/-0.91km/h, 6.78+/-1.23km/h, respectively). Measured with the Cosmed K2, a significant relationship existed between VO(2) and each speed level (r=.95, P<.0001; VO(2)=4.24x speed-7.37, standard estimation error=2.29mL.min(-1).kg(-1)).


CONCLUSIONS
Maximal VO(2) and maximal speed measured on the treadmill did not differ significantly from those obtained on the 20MST. The current 20MST equation (Léger equation) was not valid to estimate VO(2) in CAD patients. A modified prediction equation of VO(2) was given and would need a larger number of patients to be generalized.
Gayda
Mathieu
M
Faculté des Sciences du Sport, Univeristé de picardie Jules Verne, Amiens, France. said.ahmaidi@ca.u-picardie.fr
Choquet
Dominique
D
Temfemo
Abdou
A
Ahmaïdi
Saïd
S
D000203:Activities of Daily Living; D000704:Analysis of Variance; D001944:Breath Tests; D003324:Coronary Artery Disease / Q000175:diagnosis* / Q000378:metabolism* / Q000503:physiopathology; D005080:Exercise Test / Q000379:methods* / Q000592:standards; D017079:Exercise Tolerance; D006801:Humans; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption; D010809:Physical Fitness; D011237:Predictive Value of Tests; D015635:Radionuclide Ventriculography; D012044:Regression Analysis; D013318:Stroke Volume; D013997:Time Factors; D016138:Walking