Article

The goals of this study
were to validate the use of accelerometers by means of multiple linear models
(MLMs) to estimate the O2 consumption (VO2) in paraplegic persons and to
determine the best placement for accelerometers on the human
body.Setting:Non-hospitalized paraplegics' community.Methods:Twenty participants
(age=40.03 years, weight=75.8 kg and height=1.76 m) completed sedentary,
propulsion and housework activities for 10 min each. A portable gas analyzer was
used to record VO2. Additionally, four accelerometers (placed on the non-dominant
chest, non-dominant waist and both wrists) were used to collect second-by-second
acceleration signals. Minute-by-minute VO2 (ml kg(-1) min(-1)) collected from
minutes 4 to 7 was used as the dependent variable. Thirty-six features extracted
from the acceleration signals were used as independent variables. These variables
were, for each axis including the resultant vector, the percentiles 10th, 25th,
50th, 75th and 90th; the autocorrelation with lag of 1 s and three variables
extracted from wavelet analysis. The independent variables that were determined
to be statistically significant using the forward stepwise method were
subsequently analyzed using MLMs.Results:The model obtained for the non-dominant
wrist was the most accurate
(VO2=4.0558-0.0318Y25+0.0107Y90+0.0051YND2-0.0061ZND2+0.0357VR50) with an r-value
of 0.86 and a root mean square error of 2.23 ml kg(-1) min(-1).Conclusions:The
use of MLMs is appropriate to estimate VO2 by accelerometer data in paraplegic
persons. The model obtained to the non-dominant wrist accelerometer (best
placement) data improves the previous models for this population.

Langue : ANGLAIS