Physical activity assessment with accelerometers

Abstract

OBJECTIVE: Evaluation of motion sensors, speci®cally accelerometers, as an objective tool for the assessment of physical activity in large populations, over periods long enough to be representative of normal daily life and with minimal discomfort to the subjects. METHOD: Review of validation studies of accelerometers with indirect calorimetry as a reference method. Accelerometers were commercially available one-axial accelerometers: Caltrac 1 , Computer Science Application (CSA) accelerometer, Mini Motionlogger Actigraph; the tri-axial accelerometer Tritrac-R3 D; and an tri-axial accelerometer for movement registration (Tracmor) from our laboratory. RESULTS: There is no clear difference for correspondence between indirect calorimetry and accelerometer counts during level walking, whether one-axial or tri-axial and placed at the wrist, hip or low back. Sedentary activities are better re¯ected with a tri-axial accelerometer than with a one-axial accelerometer. Two accelerometers were validated in free living conditions with doubly labeled water. The highest correlation between accelerometer output and activity induced energy expenditure was found for Tracmor. CONCLUSIONS: From all accelerometers tested, the tri-axial accelerometer for movement registration is an objective method that can be used to distinguish differences in activity levels between individuals and assess the effect of interventions on physical activity within individuals.

Significant changes in physical activity among pregnant women in the UK as assessed by accelerometry and self-reported activity

“…This study has several important features. Firstly, it employed omnidirectional motion sensors, which are better for recording sedentary activity compared with mono-axial sensors (Westerkerp, 1999). Secondly, it sited the accelerometer on the ankle to increase the comfort of 72 h continuous monitoring.…”

“…The difficulties involved in taking such measurements are well established (Avons et al, 1988). Conventional techniques used within the general population include pedometry, accelerometry, heart rate monitoring and activity records obtained through diaries or recall (Westerkerp, 1999;Conway et al, 2002). Although doubly labelled water is now the gold standard for the assessment of energy expenditure, the costs associated with this method restrict its use in population studies (Goldberg et al, 1993).…”

“…Accelerometers detect the quantity and intensity of bodily movement and demonstrate a high degree of reproducibility and objectivity. Research conducted on nonpregnant populations has demonstrated significant relationships between accelerometer output and energy expenditure under a variety of circumstances (Schutz et al, 1988;Meijer et al, 1989;Bouten et al, 1996;Westerkerp, 1999;Hoos et al, 2004) as well as during a 1-day period of standardized activity in a respiration chamber (Bouten et al, 1994).…”

Long-period accelerometer monitoring shows the role of physical activity in overweight and obesity

“…[9][10][11][12] Westerterp 13 has suggested that accelerometers are an objective tool for the assessment of PA in large populations over periods long enough to be representative of normal daily life. Since an increase in PA is an effective therapeutic intervention for the prevention and treatment of obesity and its related diseases, a single-axis accelerometer has been developed in Japan for assessing daily PA over long periods (6 weeks).…”

The relationship between pedometer-determined ambulatory activity and body composition variables

“…4 One of the issues identified for physical activity assessment was an inability to quantify trends in physical activity using currently available data. 5 There is increasing interest in objective monitoring of daily physical activity using electronic motion sensors, including accelerometers 6,7 and pedometers. 8 -10 This shift was apparent in the June 2000 Research Quarterly for Exercise and Sport Measurement of Physical Activity Special Issue 11 and again in the September 2000 Medicine and Science in Sports and Exercise Measurement of Moderate Physical Activity: Advances in Assessment Techniques Issue.…”