A normative description of a motion details the necessary and sufficient criteria to identify that motion. It equips researchers with a shared lexicon for describing their research and, in this way, adoption of a normative description facilitates communication within the research community. Although there is an abundance of descriptions of sit-to-stand movement, there is not a commonly accepted normative description of sit-to-stand; study-specific descriptions are commonplace. This work evaluates the breadth of existing sit-to-stand descriptions using new experimental data from 15 healthy young adults standing from a 46 cm chair. Our goal is to develop a normative description of the sit-to-stand motion that is in harmony with the literature. After aligning experimental data to seat-off (the one sit-to-stand event with a clear definition), events defining the start of sit-to-stand, seat-off, and the end of sit-to-stand are identified using a density-based clustering method. Then, the intermediary events of start of seat unloading, end of momentum transfer, and beginning of stabilization are determined while maintaining consistent sequencing and biomechanical meaning. These six events of sit-to-stand are determined from trunk, hip, knee, and ankle angle data and vertical ground reaction forces. The events are in greatest accordance with the descriptions of sit-to-stand introduced by Schenkman et al., 1990, Kralj et al., 1990, and the event timings are in alignment with the findings of other researchers. The proposed description of healthy sit-to-stand promotes consistency in the description of this motion and adoption of this description will promote effective communication in sit-to-stand research.

运动的规范描述详细说明了识别该运动的必要和充分标准。它为研究人员提供了一个共享的词典来描述他们的研究，这样，采用规范性描述就可以促进研究团体内部的交流。尽管有很多关于坐着站立运动的描述，但是没有公认的坐着站立运动的规范描述。研究特定的描述是司空见惯的。这项工作使用来自15位健康年轻人（站在46厘米椅子上）的新实验数据，评估了现有从坐到站描述的广度。我们的目标是开发一种从坐到站运动的规范描述，使其与文献相吻合。在将实验数据与就座数据对齐后（一个清晰的坐着待命的事件），使用基于密度的聚类方法识别定义坐姿开始，就座和坐姿结束的事件。然后，确定座位卸载开始，动量传递结束和稳定开始的中间事件，同时保持一致的顺序和生物力学意义。从躯干，臀部，膝盖和脚踝角度数据以及垂直地面反作用力确定这六个坐姿到坐姿的事件。这些事件与Schenkman等人（1990年），Kralj等人（1990年）所介绍的“从坐到站”的描述最相符，并且事件发生的时间与其他研究者的发现一致。