China Health and Nutrition Survey - Child Physical Activity

Child Physical Activity

Two methods of collecting physical activity and inactivity data from respondent children were used, beginning in 1997. The first is based on questionnaires which collect reports of usual time spent in activities common in each of four settings. Activity questionnaires were designed by Popkin and Barbara Ainsworth. Ainsworth was also involved in the design and evaluation of the activity questions for the U.S. Health Interview Surveys (HIS), the MONICA Optional Study of Physical Activity (MOSPA), and more recently the new International Physical Activity questionnaire for WHO. We expanded upon the U.S. HIS questions to include activity and inactivity, including TV viewing and other sedentary activities such as using computers, playing board games, and reading. Activities in and out of school, as well as culture-specific activity at home were included.

The second method involves measurement of motion in a 24-hour period using the Caltrac actometer. A subset of Chinese children provided these data. The Caltrac is a low-cost device that looks like a beeper and is attached to the waist. It registers motion in two dimensions, and gives an estimate of total energy expenditure. The Caltrac was selected because it provides reasonably reliable and valid estimates of total activity, is cost effective, is feasible for use in a variety of field settings, is non-invasive and is well-accepted by children. Questions on sleeping time and the nature of that day for the child are also asked in conjunction with the Caltrac data. However, this was discontinued in 2004.