College of Health Solutions, Arizona State University, Phoenix, AZ, USA.
Division of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, CA, USA.
Hum Mov Sci. 2021 Dec;80:102876. doi: 10.1016/j.humov.2021.102876. Epub 2021 Sep 14.
Reactive stepping is impaired in people with Parkinson's Disease (PD) but can be improved with training. However, it is unclear if reactive steps can be improved when performing a concurrent cognitive task, a common and fall-relevant circumstance. We assessed the feasibility and preliminary effectiveness of dual-task reactive step training. Specifically, we measured whether stepping and cognitive reaction time are improved after one day of dual-task reactive step practice and if improvements are retained 24 h later. Sixteen people with PD and 13 age-matched healthy controls (HC) underwent repeated from-stance support surface perturbations that elicited a reactive step while performing an auditory Stroop task. Participants returned the following day to reassess dual-task reactive stepping performance. Cognitive, neuromuscular, and stepping outcomes were calculated. Increased step lengths were observed for both groups after practice (p < 0.001). Cognitive reaction times also improved through practice; however, this was more pronounced in the HC group (group by time interaction- p < 0.001). No changes were observed for step latency, margin of stability, or EMG onset through practice. Step length and cognitive reaction time improvements were retained 24 h after practice in both groups (step length: p < 0.001; cognitive reaction time: p = 0.05). This study provides preliminary evidence for the effectiveness of dual-task reactive step training to improve step length in people with PD. The improvements in step length without compromising cognitive reaction times suggest that participants improved reactive stepping without a robust attention shift toward the postural task. Future research is necessary to determine optimal training protocols and determine if such training protocols impact falls in PD patients.
帕金森病（PD）患者的反应性跨步能力受损，但可以通过训练得到改善。然而，在执行同时进行的认知任务时，反应性跨步是否可以改善，这在常见且与跌倒相关的情况下尚不清楚。我们评估了双重任务反应性跨步训练的可行性和初步效果。具体来说，我们测量了在一天的双重任务反应性跨步练习后，跨步和认知反应时间是否得到改善，以及 24 小时后是否仍能保持改善。16 名 PD 患者和 13 名年龄匹配的健康对照组（HC）接受了重复的从站姿支撑面扰动，在执行听觉斯特鲁普任务时引发了反应性跨步。参与者第二天返回重新评估双重任务反应性跨步表现。计算了认知、神经肌肉和跨步结果。练习后，两组的跨步长度都增加了（p<0.001）。通过练习，认知反应时间也得到了改善；然而，在 HC 组中更为明显（组间时间交互作用-p<0.001）。通过练习，步潜伏期、稳定裕度或 EMG 起始没有变化。在两组中，跨步长度和认知反应时间的改善在练习 24 小时后仍能保持（跨步长度：p<0.001；认知反应时间：p=0.05）。本研究初步证明了双重任务反应性跨步训练对改善 PD 患者跨步长度的有效性。跨步长度的改善而不影响认知反应时间表明，参与者在不向姿势任务转移注意力的情况下改善了反应性跨步。需要进一步研究来确定最佳的训练方案，并确定这种训练方案是否会影响 PD 患者的跌倒。
