Laboratório de Estudos da Motricidade Humana, Av. Generalíssimo deodoro 01, Belém 66073-00, PA, Brazil.
Instituto de Ciências Exatas e Naturais, Universidade Federal do Pará, R. Augusto Corrêa, 01, Belém 66093-020, PA, Brazil.
Gait Posture. 2022 Jul;96:9-17. doi: 10.1016/j.gaitpost.2022.05.002. Epub 2022 May 4.
Postural adjustments involve displacements of the center of mass (COM), controlled by the central nervous system (CNS), to maintain equilibrium whilst standing. Postural adjustments can be anticipatory (APAs) or compensatory (CPAs), and are triggered to counteract predictable perturbations.
Is the new smartphone application, Momentum, a valid and reliable tool for the assessment of body balance, by measuring APAs and CPAs using accelerometer readings?
20 young adults were exposed to external predictable perturbations induced at the shoulder level, whilst standing. COM linear acceleration was recorded by Momentum (extracting data from a smartphone's accelerometer) and a 3D motion capture system.
The key results demonstrated a very high, significant correlation (r ≥ 0.7, p < 0.05) between the two device settings in the APA parameters which obtained r = 0.65, denoting a high correlation. Considering the reliability, variables that are compensatory in nature are presented on a scale of good to excellent in measurement methods, kinematics, and Momentum. However, the anticipatory variables presented excellent reliability only for the kinematics.
These experiments show that Momentum is a valid method for measuring COM acceleration under predictable perturbations and is reliable for compensatory events.
姿势调整涉及到重心（COM）的位移，由中枢神经系统（CNS）控制，以在站立时保持平衡。姿势调整可以是预期的（APAs）或补偿的（CPAs），并被触发以抵消可预测的扰动。
新的智能手机应用程序 Momentum 是否可以通过使用加速度计读数来测量 APAs 和 CPAs，从而成为评估身体平衡的有效且可靠的工具？
20 名年轻成年人在肩部受到外部可预测的扰动时站立。通过 Momentum（从智能手机的加速度计中提取数据）和 3D 运动捕捉系统记录 COM 线性加速度。
主要结果表明，在获得的 APA 参数中，两种设备设置之间具有非常高的显著相关性（r≥0.7，p<0.05），相关性为 0.65，表明相关性很高。考虑到可靠性，具有补偿性质的变量在测量方法、运动学和 Momentum 方面呈现出良好到优秀的尺度。然而，仅在运动学方面，预期变量表现出极好的可靠性。
这些实验表明，Momentum 是一种在可预测的扰动下测量 COM 加速度的有效方法，并且对于补偿事件是可靠的。
