Technology to Improve Assessment of Physical Activity

描述（由申请人提供）：本研究的目的是检验LifeChek KAL-X传感器在不同模式和强度的身体活动中评估能量消耗的有效性和可靠性。我们还将检查环境条件或服装的变化是否会影响KAL-X传感器的准确性或性能。此外，我们将检查KAL-X传感器与自由生活期间自我报告的身体活动之间的相关性。这也将允许我们检查参与者是否愿意长时间佩戴该设备，以及在自由生活条件下传感器的完整性。本申请是为了响应美国国立卫生研究院最近的一个项目公告（PAR-03-009）。

DESCRIPTION (provided by applicant): The goal of this study is to examine the validity and reliability of the LifeChek KAL-X Sensor to assess energy expenditure during varying modes and intensities of physical activity. We will also examine whether environmental conditions or variations in clothing impact the accuracy or performance of the KAL-X Sensor. In addition, we will examine the correlation between the KAL-X Sensor and self-reported physical activity across a period of free-living. This will also permit us to examine if participants are willing to wear this device for an extended period of time and the integrity of the sensor under free-living conditions. This application is in response to a recent program announcement by the NIH (PAR-03-009). The proposed study will involve three phases; in Phase 1 we will compare energy expenditure from the KAL-X Sensor to a criterion measure of energy expenditure (indirect calorimetry). This will involve the subjects performing a variety of activities including the following: treadmill walking, cycle ergometry, armcrank ergometry, resistance exercise, and a simulation of lifestyle activity. Each activity session will be performed on a separate day with energy expenditure estimated using the LifeChek KAL-X Sensor and the criterion measure of energy expenditure will be indirect calorimetry. To assess whether variations in bodyweight and body size impact the accuracy of the KAL-X Sensor, we will recruit equal numbers of men and women from three body mass index categories (20-24.9 kg/m 2, 25-29.9 kg/m 2, 30-35 kg/m2). Based on a power analysis, 48 subjects (16 in each body mass index category) will be recruited to participate in this study. In Phase 2 subjects will perform an outdoor activity for a period of approximately 60 minutes. Again, energy expenditure will be estimated using the LifeChek KAL-X Sensor and the criterion measure of energy expenditure will be indirect calorimetry. We will also monitor environmental conditions (temperature, humidity, and cloud cover) to assess whether these factors impact the accuracy of the KAL-X Sensor. In Phase 3 subjects will wear the KAL-X Sensor for a one-week period under free-living conditions. This will allow us to compare energy expenditure from the KAL-X Sensor with energy expenditure estimated from self-report using a questionnaire. Moreover, we will be able to examine if participants are willing to wear this device and the integrity of the KAL-X Sensor under free-living conditions. We hypothesize that there will be no significant difference between the measurements of energy expenditure in the validation study between the KAL-X Sensor and indirect calorimetry. In addition, we hypothesize that clothing and environmental conditions will not affect the accuracy or reliability of the KAL-X Sensor. Moreover, we hypothesize that subjects will be willing to wear the KAL-X Sensor and that the sensor will be reliable under free-living conditions. The KAL-X Sensor is an innovative technology that may revolutionize the assessment of energy expenditure and may have implications for improving outcomes in clinical programs.