Use of the peak heart rate reached during six-minute walk test to predict individualized training intensity in patients with cystic fibrosis: validity and reliability.
OBJECTIVE
To determine whether the peak heart rate reached during a six-minute walk test (HR(6peak)) can be used to predict the heart rate determined at the gas exchange threshold (HR(GET)) during a maximal cardiopulmonary exercise test (CPET) in patients with cystic fibrosis (CF). To assess the test-retest reliability of HR(6peak).


METHODS
Case-control and reliability study.


METHODS
CF unit.


METHODS
Adults with CF (n=23) and age-matched sedentary subjects (control group, n=17).


METHODS
Not applicable.


METHODS
Six-minute walk test, HR(6peak), CPET, and HR(GET).


RESULTS
HR(GET) and HR(6peak) were not significantly different and were highly correlated in both groups (CF, r=.91, P<.01; controls, r=.81, P<.01). The mean differences (HR(6peak)-HR(GET)) for patients with CF and control subjects were, respectively, -0.9 beats.min(-1) (bpm) and -0.1 bpm, with neither significantly different from 0. The limits of agreements were +/-11 bpm and +/-18 bpm, respectively. HR(6peak) demonstrated excellent relative reliability (intraclass correlation coefficient=.93) and was associated with low variability (standard error of measurement=4.9 bpm) in patients with CF.


CONCLUSIONS
HR(6peak) is valid and demonstrates satisfactory test-retest reliability in patients with CF. These results might suggest the use of HR(6peak) as a simple alternative method to individualize exercise prescriptions in this population. Further studies are needed in a larger cohort of patients to confirm these preliminary findings.
Gruet
Mathieu
M
Laboratoire HandiBio, Université du sud Toulon-Var, Toulon, France.
Brisswalter
Jeanick
J
Mely
Laurent
L
Vallier
Jean-Marc
JM
D000328:Adult; D015992:Body Mass Index; D003550:Cystic Fibrosis / Q000503:physiopathology*; D005080:Exercise Test / Q000379:methods*; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D010809:Physical Fitness; D015203:Reproducibility of Results; D012129:Respiratory Function Tests; D016138:Walking