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Maximum walking speeds obtained using treadmill and overground robot system in persons with post-stroke hemiplegia.

Capó-Lugo CE, Mullens CH, Brown DA - J Neuroeng Rehabil (2012)

Bottom Line: Subjects achieved these faster speeds by initially increasing both step length and cadence and, once individuals stopped increasing their step length, by only increasing cadence.With post-stroke hemiplegia, individuals are able to walk at faster speeds than their SMWS overground, when provided with a safe environment that provides external forces that requires them to attempt dynamic stability maintenance at higher gait speeds.Therefore, this study suggests the possibility that, given the appropriate conditions, people post-stroke can be trained at higher speeds than previously attempted.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Physical Therapy and Human Movement Sciences, Northwestern University, Chicago, IL 60611, USA. carmen.capo@u.northwestern.edu

ABSTRACT

Background: Previous studies demonstrated that stroke survivors have a limited capacity to increase their walking speeds beyond their self-selected maximum walking speed (SMWS). The purpose of this study was to determine the capacity of stroke survivors to reach faster speeds than their SMWS while walking on a treadmill belt or while being pushed by a robotic system (i.e. "push mode").

Methods: Eighteen chronic stroke survivors with hemiplegia were involved in the study. We calculated their self-selected comfortable walking speed (SCWS) and SMWS overground using a 5-meter walk test (5-MWT). Then, they were exposed to walking at increased speeds, on a treadmill and while in "push mode" in an overground robotic device, the KineAssist, until they were tested at a speed that they could not sustain without losing balance. We recorded the time and number of steps during each trial and calculated gait speed, average cadence and average step length.

Results: Maximum walking speed in the "push mode" was 13% higher than the maximum walking speed on the treadmill and both were higher ("push mode": 61%; treadmill: 40%) than the maximum walking speed overground. Subjects achieved these faster speeds by initially increasing both step length and cadence and, once individuals stopped increasing their step length, by only increasing cadence.

Conclusions: With post-stroke hemiplegia, individuals are able to walk at faster speeds than their SMWS overground, when provided with a safe environment that provides external forces that requires them to attempt dynamic stability maintenance at higher gait speeds. Therefore, this study suggests the possibility that, given the appropriate conditions, people post-stroke can be trained at higher speeds than previously attempted.

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Related in: MedlinePlus

Force applied at the pelvic mechanism of the robotic device by each healthy (n=7) individual while walking at three different speeds: slow (blue), comfortable (green), and fast (red) while in the robotic device’s non-“push mode” (top force profiles) and “push mode” (bottom force profiles).
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Figure 3: Force applied at the pelvic mechanism of the robotic device by each healthy (n=7) individual while walking at three different speeds: slow (blue), comfortable (green), and fast (red) while in the robotic device’s non-“push mode” (top force profiles) and “push mode” (bottom force profiles).

Mentions: In the mini-experiment to characterize the force requirements that were necessary to interact with the KineAssist during the “push mode” versus the non-“push mode”, we observed that the force applied at the pelvis by healthy participants during walking in the robotic device required less force generation during the “push mode” at a given speed than when walking in the robotic device without being pushed (Figure 3). In fact, the force profiles for each individual seem to indicate that in the “push mode” the same amount of force was produced regardless of the walking speed in which they were “pushed” (Figure 3).


Maximum walking speeds obtained using treadmill and overground robot system in persons with post-stroke hemiplegia.

Capó-Lugo CE, Mullens CH, Brown DA - J Neuroeng Rehabil (2012)

Force applied at the pelvic mechanism of the robotic device by each healthy (n=7) individual while walking at three different speeds: slow (blue), comfortable (green), and fast (red) while in the robotic device’s non-“push mode” (top force profiles) and “push mode” (bottom force profiles).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3539927&req=5

Figure 3: Force applied at the pelvic mechanism of the robotic device by each healthy (n=7) individual while walking at three different speeds: slow (blue), comfortable (green), and fast (red) while in the robotic device’s non-“push mode” (top force profiles) and “push mode” (bottom force profiles).
Mentions: In the mini-experiment to characterize the force requirements that were necessary to interact with the KineAssist during the “push mode” versus the non-“push mode”, we observed that the force applied at the pelvis by healthy participants during walking in the robotic device required less force generation during the “push mode” at a given speed than when walking in the robotic device without being pushed (Figure 3). In fact, the force profiles for each individual seem to indicate that in the “push mode” the same amount of force was produced regardless of the walking speed in which they were “pushed” (Figure 3).

Bottom Line: Subjects achieved these faster speeds by initially increasing both step length and cadence and, once individuals stopped increasing their step length, by only increasing cadence.With post-stroke hemiplegia, individuals are able to walk at faster speeds than their SMWS overground, when provided with a safe environment that provides external forces that requires them to attempt dynamic stability maintenance at higher gait speeds.Therefore, this study suggests the possibility that, given the appropriate conditions, people post-stroke can be trained at higher speeds than previously attempted.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Physical Therapy and Human Movement Sciences, Northwestern University, Chicago, IL 60611, USA. carmen.capo@u.northwestern.edu

ABSTRACT

Background: Previous studies demonstrated that stroke survivors have a limited capacity to increase their walking speeds beyond their self-selected maximum walking speed (SMWS). The purpose of this study was to determine the capacity of stroke survivors to reach faster speeds than their SMWS while walking on a treadmill belt or while being pushed by a robotic system (i.e. "push mode").

Methods: Eighteen chronic stroke survivors with hemiplegia were involved in the study. We calculated their self-selected comfortable walking speed (SCWS) and SMWS overground using a 5-meter walk test (5-MWT). Then, they were exposed to walking at increased speeds, on a treadmill and while in "push mode" in an overground robotic device, the KineAssist, until they were tested at a speed that they could not sustain without losing balance. We recorded the time and number of steps during each trial and calculated gait speed, average cadence and average step length.

Results: Maximum walking speed in the "push mode" was 13% higher than the maximum walking speed on the treadmill and both were higher ("push mode": 61%; treadmill: 40%) than the maximum walking speed overground. Subjects achieved these faster speeds by initially increasing both step length and cadence and, once individuals stopped increasing their step length, by only increasing cadence.

Conclusions: With post-stroke hemiplegia, individuals are able to walk at faster speeds than their SMWS overground, when provided with a safe environment that provides external forces that requires them to attempt dynamic stability maintenance at higher gait speeds. Therefore, this study suggests the possibility that, given the appropriate conditions, people post-stroke can be trained at higher speeds than previously attempted.

Show MeSH
Related in: MedlinePlus