Article

Assessment of physical activity with the Computer Science and Applications, Inc., accelerometer: laboratory versus field validation.

Department of Exercise and Nutritional Sciences, San Diego State University, USA.
Research quarterly for exercise and sport (impact factor: 1.49). 03/2000; 71(1):36-43. pp.36-43
Source: PubMed

ABSTRACT Our purpose was to compare the validity of the Computer Science and Applications, (CSA) Inc., accelerometer in laboratory and field settings and establish CSA count ranges for light, moderate, and vigorous physical activity. Validity was determined in 60 adults during treadmill exercise, using oxygen consumption (VO2) as the criterion measure, while 30 adults walked and jogged outdoors on a 400-m track. The relationship between CSA counts and VO2 was linear (R2 = .89 SEE = 3.72 ml.kg-1.min-1), as was the relationship between velocity and counts in the field (R2 = .89, SEE = 0.89 mi.hr-1). However, significant differences were found (p < .05) between laboratory and field measures of CSA counts for light and vigorous intensity. We conclude that the CSA can be used to quantify walking and jogging outdoors on level ground; however, laboratory equations may not be appropriate for use in field settings, particularly for light and vigorous activity.

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Keywords

60 adults
 
accelerometer
 
Computer Science
 
counts
 
criterion measure
 
CSA count ranges
 
CSA counts
 
field measures
 
field settings
 
jogged outdoors
 
jogging outdoors
 
laboratory equations
 
moderate
 
treadmill exercise
 
vigorous physical activity