Physical Activity Measurement in Older Adults

描述（由申请人提供）：虽然对身体活动的有效测量通常是困难的，但考虑到老年人参与的活动总量和强度相对较低，对老年人的测量尤其具有挑战性。与能量消耗的直接测量方法（如双标签水）相比，自我报告显示出有限的有效性，并且在老年人群中，这种方法可能存在特别的问题（例如认知受损）。对于评估老年人目前的身体活动水平，客观监测可能是特别有利的，如果被证明是有效的，将有助于未来试图描述身体活动与健康之间关系的研究。该研究的主要假设是，与直接测量体力活动能量消耗（双标签水和间接量热法）相比，多传感器体力活动监测仪将比自我报告具有更高的精度。此外，单个传感器监视器，无论是单独使用还是与选定的自我报告项目结合使用，都比单独使用自我报告具有更高的精度。年龄在65岁或以上的男性和女性（n=60）将被纳入本研究。在为期十天的能量消耗测量中，受试者将佩戴计步器、单轴加速度计和多传感器监测器（加速度计、皮肤电反应、温度），并完成三份自我报告问卷，以评估身体活动。单传感器和多传感器监测器也将与在较小样本（n=20）中在整个房间内停留24小时的量热计一起佩戴，以更精确地评估其测量特性。将使用相关性、一致性限和回归分析来确定测量的有效性，无论是单独的还是组合的，与体力活动能量消耗测量相比较。这项拟议的研究将提供最精确和准确的方法来测量老年人由于体育活动而消耗的能量。这种方法可以被纳入未来的研究，以检验体育活动剂量与各种健康结果之间的关系。

DESCRIPTION (provided by applicant): While the valid measurement of physical activity is generally difficult, measurement in older adults is particularly challenging given the relatively low levels of both total activity and intensity of the activities in which they participate. Self-report has shown limited validity when compared to direct measures of energy expenditure such as doubly labeled water, and there may be particular issues of concern with this methodology in older populations (e.g. impaired cognition). For the assessment of current physical activity levels in older adults, objective monitoring may be particularly advantageous, and if proven valid, will aid in future studies attempting to delineate the associations between physical activity and health. The primary hypothesis of the proposed study is that multiple sensor physical activity monitors will have greater precision than self-report when compared to direct measures of physical activity energy expenditure (doubly labeled water and indirect calorimetry). Additionally, single sensor monitors, either alone or in combination with selected self-report items, will have greater precision than self-report alone. Men and women (n=60), aged 65 or older, will be enrolled in this study. During ten days of energy expenditure measurement via doubly labeled water, subjects will wear a pedometer, a uniaxial accelerometer, and a multiple sensor monitor (accelerometer, galvanic skin response, temperature), and complete three self-report questionnaires for the assessment of physical activity. Single and multiple sensor monitors will also be worn in conjunction with a 24-hour stay in a whole room calorimeter in a smaller sample (n=20) to more precisely evaluate their measurement properties. Correlation, limits of agreement, and regression analyses will be used to determine the validity of the measures either independently, or in combinations, compared to the physical activity energy expenditure measurements. The proposed study will give insight into the most precise and accurate method of measuring current energy expenditure due to physical activity among older adults. This methodology can then be incorporated into future studies examining the associations between doses of physical activity and various health outcomes.