Maltais Désirée, Bar-Or Oded, Pierrynowski Michael, Galea Victoria
Children's Exercise and Nutrition Centre, Department of Pediatrics, Chedoke Hospital Division, McMaster University, Hamilton, Ontario L8N 3Z5, Canada.
Med Sci Sports Exerc. 2003 Oct;35(10):1653-61. doi: 10.1249/01.MSS.0000089343.67237.50.
To determine whether physiologic responses during treadmill walking in children with cerebral palsy (CP) are affected by repeated walking bouts on different days, and whether effects are different at different speeds.
Three girls and five boys (9.2-15.7 yr, 23.3-64.4 kg) with mild CP received 12-15 min of treadmill walking practice and had their fastest walking speed (FWS) determined during an introductory visit. During each of three subsequent visits (day 1, day 2, day 3), subjects walked for 3 min at 60, 75, and 90% FWS. Resting physiologic measures were taken on day 1.
From day 1 to day 3, net ventilation ([OV0312]E), and net heart rate (HR) at 90% FWS decreased by 3.6 L.min-1 and 8 beats.min-1, respectively. There were no differences between day 1 and day 2 or day 1 and day 3 for any other physiologic variable at any speed. Day 3 was less than day 2 for net HR (60% FWS) and, independent of speed, net [OV0312]O2 (per kilogram of body mass and per stride) and net energy expenditure (kJ.min-1). Between-day reliability (R) of physiologic responses was > or = 0.95, except respiratory rate (R = 0.75). Intrasubject, between-day variability for the [OV0312]O2 measures was 7.6-12.9%.
Because there were no day 1 to day 3 reductions in metabolic variables, day 1 to day 3 reductions at 90% FWS in net HR may reflect decreased emotional stress over time and reductions in net [OV0312]E, an uncoupling of [OV0312]O2 and [OV0312]E. Despite between-day differences, reliable net physiologic and stable net metabolic variables may be collected in subjects with mild CP after one treadmill walking practice session.
确定脑瘫（CP）患儿在跑步机上行走时的生理反应是否受到不同日期重复行走回合的影响，以及不同速度下的影响是否不同。
三名女孩和五名男孩（9.2 - 15.7岁，23.3 - 64.4千克）患有轻度CP，接受了12 - 15分钟的跑步机行走练习，并在初次就诊时确定了他们的最快行走速度（FWS）。在随后的三次就诊（第1天、第2天、第3天）中，受试者分别以FWS的60%、75%和90%的速度行走3分钟。在第1天进行静息生理指标测量。
从第1天到第3天，90% FWS时的净通气量（[OV0312]E）和净心率（HR）分别下降了3.6升·分钟-1和8次·分钟-1。在任何速度下，第1天和第2天或第1天和第3天之间的任何其他生理变量均无差异。第3天的净HR（60% FWS）低于第2天，且与速度无关，净[OV0312]O2（每千克体重和每步）和净能量消耗（千焦·分钟-1）也低于第2天。除呼吸频率（R = 0.75）外，生理反应的日间可靠性（R）≥0.95。[OVC0312]O2测量的受试者内日间变异性为7.6 - 12.9%。
由于代谢变量在第1天到第3天没有下降，90% FWS时第1天到第3天净HR的下降可能反映了随着时间推移情绪压力的降低以及净[OV0312]E的下降，即[OV0312]O2和[OV0312]E的解耦。尽管存在日间差异，但在一次跑步机行走练习后，轻度CP受试者仍可收集到可靠的净生理指标和稳定的净代谢变量。
