应用计步器测量日常体力活动的研究

Utility of pedometer to assess daily physical activity

背景:计步器作为一种简便实用的体力活动测量工具,在研究和干预人群体力活动方面具有广泛的应用价值,国外学者已对其开展大量研究。目的:验证计步器测量中国大学生人群体力活动的有效性。时间及地点:试验于2007-04/06在南京体育学院运动人体科学实验室完成。对象:随机选取南京体育学院运动人体科学专业、社会体育专业大学生各15名,共计30名,其中男生15名,女生15名,平均年龄(20±1)岁。方法:受试者佩带Digi-Walker200型计步器1周,记录每日计步器计数;每日填写Bouchard体力活动日记,回忆每日24h活动情况,并据此计算一天总能量消耗;1周后填写国际体力活动问卷,内容包括1周大强度活动、中等强度活动、步行和静坐情况。主要观察指标:每日步数与每日能量消耗、每日静坐时间、每日步行时间、每日运动时间及1周活动水平的关系。结果:步数与日记法记录的一天总能量消耗、步行时间、步行时间呈现中度正相关,与静坐时间呈现中度负相关;不同体力活动水平受试者其步数差异有显著性意义,步数越多,越能真实地反映体力活动水平,运动或连续步行(超过15min)可以显著增加步数,一天若包含30min的中等强度体力活动基本能够达到或超过10000步/d的目标步数。结论:计步器可以相对客观地反映体力活动总体水平,但其难以提供活动强度、活动时间方面的具体信息。

BACKGROUND： As a convenient and useful physical activity measurement tool, pedometer is widely used in research and intervention about physical activity of population. OBJECTIVE： To assess validity and reliability of the pedometer in measuring daily physical activity. DESIGN, TIME AND SETTING： The experiment was performed at the Department of Kinesiology, Nanjing Institute of Physical Education and Sports from April to June 2007. PARTICIPANTS： Thirty college students, 15 majoring in Kinesiology and 15 majoring in social and physical education, 15 females and 15 males, with an average age of （20±1） years, were selected from Nanjing Institute of Physical Education and Sports. METHODS： Participants wore a Digi-Walker200 for one week torecord results of pedometer measurement, and filled in Bouchard Physical Activity Diary every day to note activity in 24 hours and calculate energy consumption. All participants completed International Physical Activity Questionnaire including large and moderate intensity activity, walking and sitting in a week. MAIN OUTCOME MEASURES： Daily steps, energy expenditure, sedentary time, waking time, exercise time, and weekly physical activity condition. RESULTS： Step counts were positively correlated with daily energy expenditure, walking time, and exercise time, and negatively related with sedentary time. Step counts of different physical activity levels were significantly different： more step counts could better reflect physical activity levels. Furthermore, exercise or continuous walking （more than 15 minutes） could significantly increase step counts. Daily physical activity including 30-minute moderate intensity activity could achieve or exceed the target steps of 10 000. CONCLUSION： Pedometer provides a useful and objective indicator of daily step counts assessing daily physical activity, but it is difficult to reflect activity intensity and patterns.