a Laboratory for Neuromechanics and Biorobotics, Department of Automation, Biocybernetics and Robotics , Jožef Stefan Institute , Ljubljana 1000 , Slovenia.
b Jožef Stefan International Postgraduate School , Ljubljana , Slovenia.
Ergonomics. 2019 May;62(5):657-667. doi: 10.1080/00140139.2018.1559363. Epub 2019 Feb 5.
Stairways, public transport and inclined walkways are often considered as sites with higher likelihood of falls due to a sudden loss of balance. Such sites are usually marked with warning signs, equipped with non-slip surfaces and handles or handrails to avert or decrease this likelihood. Especially, handles are supposed to provide additional support in cases of a sudden loss of balance. However, the mechanisms of using handles for balance at different heights are not yet fully disclosed. We simulated full body perturbations by applying an anterior force to the waist and investigated effectiveness and mechanisms of balance recovery in five different postures: step stance and normal stance with or without holding handles at different heights. Results indicate that both step stance and holding handles at different vertical positions sufficiently assist balance recovery, compared to normal stance. While there was no significant effect of handle in CoM displacement, the shoulder height handle required the lowest handle force, indicating a difference in using the handle. To investigate handle use for balance recovery, we perturbed healthy young adults in different standing positions. Even though the use of different handles had a similar effect, the lowest forces were exerted on the shoulder height handle indicating a preferred handle position for balance recovery. AP: antero-posterior; CNS: Central nervous system; CoM: Center of Mass; CoMmax: Maximal displacement of the center of mass; CoP: Center of pressure; FHmax: Maximal resultant force exerted on the handle; hFHmax: Maximal horizontal force exerted on the handle; vFHmax; Maximal vertical force exerted on the handle; M1-M8: Perturbation force magnitude.
楼梯、公共交通工具和倾斜人行道通常被认为是更容易发生跌倒的地方，因为这些地方可能会突然失去平衡。这些地方通常会有警示标志，配备防滑表面和把手或扶手，以避免或减少这种可能性。特别是，把手应该在突然失去平衡时提供额外的支撑。然而，在不同高度使用把手来保持平衡的机制尚未完全揭示。我们通过在前腰部施加向前的力来模拟全身扰动，并研究了在五种不同姿势下（站立姿势和正常站立姿势，以及在不同高度是否握住把手）平衡恢复的有效性和机制：步姿和正常站立姿势，以及在不同高度握住把手。结果表明，与正常站立姿势相比，步姿和在不同垂直位置握住把手都能充分帮助恢复平衡。虽然把手对 CoM 位移没有显著影响，但肩部高度的把手所需的把手力最低，表明使用把手的方式不同。为了研究把手在平衡恢复中的使用，我们让健康的年轻人在不同的站立姿势下受到扰动。即使使用不同的把手有相似的效果，但肩部高度的把手所需的力最小，这表明肩部高度的把手是平衡恢复的首选把手位置。AP：前后；CNS：中枢神经系统；CoM：质心；CoMmax：质心最大位移；CoP：压力中心；FHmax：施加在把手上的最大合力；hFHmax：施加在把手上的最大水平力；vFHmax：施加在把手上的最大垂直力；M1-M8：扰动力大小。
