Article

OBJECTIVES: To assess the reproducibility and validity of the six-minute walk
test (6MWT) and predictors of the six-minute walk distance (6MWD) in adolescents
with overweight or obesity and intellectual disability (ID).
STUDY DESIGN:
Sixty-one adolescents with overweight or obesity and mild-to-moderate ID
(intelligent quotient [IQ] 40-70; age 14-22 years) participated in this study. To
test reproducibility, 39 of the participants performed the 6MWT twice with an
interval of 1 week. To test validity (n = 39), peak oxygen uptake (peak VO(2))
was measured on a bicycle ergometer. For the predictor study (n = 61), weight,
height, peak VO(2) and quadriceps strength were measured, and IQ and orthopedic
conditions were collected from the participants' medical records. RESULTS: There
was no significant difference between the means of the two 6MWTs (571.3 vs. 576.5
m; p = 0.452). The intraclass correlation coefficient was 0.82, indicating good
reliability. The smallest real difference was 82.6 m. 6MWD correlated
significantly with relative peak VO(2) (beta = 0.69) indicating validity.
Relative peak VO(2), height, IQ, body mass index (BMI) and quadriceps strength
are predictors of the 6MWD in this population. CONCLUSION: 6MWT is a reliable and
valid test in adolescents with overweight or obesity and ID. Low IQ,
overweight/obesity and low physical fitness contribute to the outcome of the
6MWT.

Langue : ANGLAIS