Abstract During pregnancy, changes in physical function, such as increases in the mass and volume of the abdomen, affect spinal alignment and the postural control system. Pregnant women often experience changes in motion patterns, as well as an increased risk of falling, during routine tasks such as rising from a chair and carrying objects. The present study aimed to analyze changes in motion patterns among pregnant women when performing a motion task involving rising from a chair, picking up plates, and walking forward while carrying the plates after turning. The study participants were nine pregnant and seven nulliparous women. The pregnant women were examined between the 16th and 18th, 24th and 25th and 32nd and 33rd weeks of gestation. The nulliparous women were examined on one occasion. Reflective markers were attached to anatomical landmarks on the participants, after which, their motion was captured using a three-dimensional motion analysis system and force plates. During a series of motions, displacement and velocity of the center of pressure (COP) coordinates and ground reaction forces (GRFs) were calculated. Differences in the COP displacement for anticipatory postural adjustments, variation in the COP velocity, and second peak value of vertical GRF during gait initiation were observed between pregnant and nulliparous women. In pregnant women, changes in strategies involving changing direction were observed at gait initiation. These findings suggest that, to reduce the risk of falls, instruction regarding motion in consideration of environmental factors during pregnancy is needed, as are interventions for the postural control system.

中文翻译：

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孕妇从椅子上起身后搬运物品时转身运动模式的变化

摘要 在怀孕期间，身体机能的变化，如腹部质量和体积的增加，会影响脊柱排列和姿势控制系统。孕妇在日常工作（例如从椅子上起身和搬运物品）中，经常会经历运动模式的变化，以及摔倒的风险增加。本研究旨在分析孕妇在执行包括从椅子上起身、拿起盘子以及转身后携带盘子向前走的运动任务时的运动模式变化。研究参与者是九名孕妇和七名未生育妇女。孕妇在妊娠第 16 周和第 18 周、第 24 周和第 25 周以及第 32 周和第 33 周之间接受检查。对这些未生育妇女进行了一次检查。反射标记被附加到参与者的解剖标志上，之后，他们的运动被使用 3D 运动分析系统和测力板捕获。在一系列运动过程中，计算了压力中心 (COP) 坐标和地面反作用力 (GRF) 的位移和速度。在孕妇和未产妇之间观察到用于预期姿势调整的 COP 位移的差异、COP 速度的变化以及步态开始期间垂直 GRF 的第二个峰值。在孕妇中，在步态开始时观察到涉及改变方向的策略变化。这些发现表明，为了降低跌倒的风险，需要在怀孕期间考虑环境因素进行运动指导，