Sports Medicine Division, Department of Medical and Surgical Sciences, University of Padova , Padova, Italy.
J Sports Sci Med. 2012 Mar 1;11(1):57-63. eCollection 2012.
This study was performed to assess the validity of the MyWellness Key (MWK) accelerometer during a treadmill-based protocol. The identification of different exercise intensities is imperative to objectively measure time spent at a specified exercise intensity. Thirty subjects, 15 men and 15 women (age = 24.5 ± 2.6 years; body mass index = 22.5 ± 2.5 kg·m(-1)), participated in a 4-phase treadmill protocol (5 minutes each one) using three different walking velocities (3, 4.5, and 6 km·h(-1)) and run (8 km·h(-1)) while outfitted with a MWK uniaxial accelerometer. Oxygen consumption was measured by indirect calorimetry (ICVO2).
The relationship between VO2 predicted from MWK (MWKVO2) and oxygen consumption (VO2 (ICVO2)), yielded a high and significant correlation (r = 0. 944; p < 0.001) with standard error of estimate (SEE) = 2.42 mL·kg(-1)·min(-1). The average differences between the two methods (MWKVO2 - ICVO2) were -0.79 (-8. 8% at 3 km·h(-1)), -0.02 (-0.2% at 4.5 km·h(-1)), 0.51 (3.3% at 6 km·h(-1)) and -0.74 (-2.7% at 8 km·h(-1)) ml·kg(-1)·min(-1). Only the 3 km·h(-1) speed showed a difference when compared to the criterion measure (p < 0.001). Bland and Altman analysis revealed less than a 1 MET difference in the mean at each point estimate and relatively tight distribution with the standard errors, especially with the 2 moderate walking speeds.
We found a high correlation between oxygen utilization and the MWK with low standard errors estimates. This indicates that this accelerometer can be used to identify exercise intensities that are related to walking and running. Key pointsFirst laboratory validation of a new uniaxial accelerometer, the MyWellness Key.Results indicate a good exercise intensity prediction during walking at moderate to high speeds.Comparing with other laboratory validations, MyWellness Key exercise intensity detection is aligned with other accelerometers.MyWellness Key can be used to give valid measurements for a range of ambulatory activity in addition to the capabilities to give real-time feedback to the participant in health promotion studies.
本研究旨在评估 MyWellness Key（MWK）加速度计在跑步机测试方案中的有效性。为了客观地测量特定运动强度下的时间，识别不同的运动强度至关重要。30 名受试者，15 名男性和 15 名女性（年龄=24.5±2.6 岁；体重指数=22.5±2.5kg·m(-1))，使用三种不同的步行速度（3、4.5 和 6km·h(-1)) 和跑步（8km·h(-1))进行了 4 个阶段的跑步机测试（每个阶段 5 分钟），同时配备了 MWK 单轴加速度计。通过间接测热法（ICVO2）测量耗氧量。
MWK 预测的 VO2（MWKVO2）与耗氧量（VO2（ICVO2））之间的关系具有高度显著的相关性（r=0.944；p<0.001），估计标准误差（SEE）=2.42ml·kg(-1)·min(-1)。两种方法（MWKVO2-ICVO2）的平均差异为-0.79（在 3km·h(-1)下为-8.8%），-0.02（在 4.5km·h(-1)下为-0.2%），0.51（在 6km·h(-1)下为 3.3%）和-0.74（在 8km·h(-1)下为-2.7%）ml·kg(-1)·min(-1)。只有 3km·h(-1)的速度与标准测量值存在差异（p<0.001）。Bland 和 Altman 分析显示，在每个点估计的平均误差中，差异小于 1MET，且分布较为紧密，尤其是在 2 个中等步行速度下。
我们发现耗氧量与 MWK 之间具有高度相关性，且估计标准误差较低。这表明该加速度计可用于识别与步行和跑步相关的运动强度。关键点：
首次对新型单轴加速度计 MyWellness Key 进行实验室验证。
结果表明，在中高速步行时，对运动强度的预测较好。
与其他实验室验证相比，MyWellness Key 的运动强度检测与其他加速度计一致。
MyWellness Key 除了能够对各种日常活动进行有效的测量外，还可以为健康促进研究中的参与者提供实时反馈。
