CALIBRATION OF THE COMPUTER SCIENCE AND APPLICATIONS, INC. (CSA) ACCELEROMETER 256

Monitoring physical activity with electronic devices that use non-volatile memory is an attractive technology as it allows the user to examine patterns in physical activity as well as total activity. A new device that may be used for such purposes is the CSA accelerometer (model #7164). The device is small(5 × 5 × 1.5 cm, 70gm) which makes it particularly useful for evaluating activity in children. The aim of this study was to examine the relationship between measured METS and the 7164 accelerometer counts/min for children (age range = 6-17 yrs.). Eighty subjects (41F, 39M) completed 3, 5min treadmill conditions (2 walking and 1 jogging). CSA counts and respiratory gas exchange measures were monitored min-by-min with average of min 4 and 5 used for analysis. 50 subjects (23F, 27M) were randomly selected as the development group and 30 subjects (18F, 12M) served as the validation group. Regression analysis was used to select the significant predictors of METS: METS = 5.6832+ 0.00093(cts/min) - 0.2613(age in yrs) (R2 = 0.83). Cross-validation results (n=30) revealed no significant difference between actual and predicted METS. Pearson r = 0.86 between actual and predicted METS (SEE = ± 1.29 METS). In conclusion, these results indicate that accelerometer counts can be used to estimate different intensities of physical activity in children.