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Robert Iansek - One of the best experts on this subject based on the ideXlab platform.
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gait in huntington s disease and the Stride Length cadence relationship
BMC Neurology, 2014Co-Authors: Robert Iansek, Mary DanoudisAbstract:The progressive deterioration of gait in Huntington’s disease (HD) leads to functional decline and loss of function. To understand the underlying mechanisms responsible for the gait changes in HD, we examined the automatic control of gait by measuring the relationship between Stride Length and cadence. The relationship is strongly linked in healthy adults during automatic gait but disrupted in pathological gait disorders, such as Parkinson’s disease (PD). The Stride Length cadence relationship was compared between seventeen participants with HD, twenty with PD and twenty one healthy older adults (HOA). Participants had their gait recorded at self-selected preferred, very slow, slow, fast and very fast speeds. Linear regression analysis was used to determine the slope and intercept of the relationship which were compared between groups. The adjustment of Stride Length and cadence when changing gait speeds was measured and compared within and between groups. Linearity was strong in all but two participants with HD and one with PD. Slope did not differ between groups (p > 0.05) but intercept was lower in the HD and PD groups compared to HOA (p 0.05) regardless of speed. The HD group adjusted Stride Length and cadence similar to HOA when changing speed. The range of cadence across speed conditions did not differ between groups. Scaling of Stride Length but not the regulation of cadence was found to be disrupted in participants with HD.
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central gait control mechanisms and the Stride Length cadence relationship
Gait & Posture, 2011Co-Authors: Thorlene Egerton, Mary Danoudis, Frances Huxham, Robert IansekAbstract:Abstract The Stride Length – cadence relationship (SLCrel) was investigated to explore a theory of two alternate but inter-related pathways for gait control. Sixty-three healthy people in three age groups walked along a computerized walkway (GAITRite®) at five self-selected speeds from very slow to very fast, five cadences from 70 to 150 steps/min and five Stride Lengths from 0.8 to 1.6 m. The data points from two walks in each level of each condition were examined for linear and quadratic relationships. In the self-selected speed condition 97% of participants had a positive linear or quadratic relationship of R2 ≥ 0.90. The quadratic relationships showed Stride Length decreased with very high cadences. When walks with cadences above 150 steps/min were removed, 95% of participants had a positive linear relationship of R2 ≥ 0.90. No age-related differences were found in slope or intercept of linear relationships or in maximum, minimum or range of Stride Length or cadence in the self-selected speed condition. In the cadence and Stride Length conditions, only 32% and 14% of positive linear or quadratic relationships were R2 ≥ 0.90. The near-invariant SLCrel, unaffected by ageing that exists for nearly all individuals when walking at self-selected speeds, indicates that the SLCrel may be used to simplify central control of automatic gait in healthy individuals. The current investigation also provides SLCrel data for healthy people which can be compared with patient populations.
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Abnormalities in the Stride Length‐cadence relation in parkinsonian gait
Movement Disorders, 1998Co-Authors: Meg E Morris, Robert Iansek, Thomas A Matyas, Jeffery J SummersAbstract:The purpose of this investigation was to clarify abnormalities in the Stride Length-cadence relation in gait hypokinesia in Parkinson's disease (PD). A second aim was to investigate the effect of levodopa medication on the foot-step pattern. In the first experiment, 20 subjects with idiopathic PD and 20 age-, sex-, and height-matched controls performed a series of 10 m walking trials at cadence rates ranging from 40 steps/min to 180 steps/min. Cadence rates were set by an electronic metronome, and gait patterns were measured by using a footswitch Stride-analyzer system. By instructing subjects to concentrate on walking in time to the metronome beat, the baseline Stride Length could be monitored for a range of velocities with the compensatory effects of cadence removed. Linear-regression analysis revealed that the mean slope for the regression of Stride Length against cadence was not different form normal in PD, although there was a statistically significant difference in mean intercept between the PD group (0.25) and the control group (0.59); [t (19) = −4.76; p = 0.0001]. The second experiment evaluated the effects of levodopa on StrideLength regulation in 10 subjects with idiopathic PD on average 45 min before and after the first morning dose was administred. There was a statistically significant increase in Stride Length for all cadence rates from premedication to postmedication phases and the maximal Stride Length was achieved at higher cadence rates after medication. The slope of the regression of Stride Length against cadence did not alter according to medication status, although the mean intercept was significantly lower before levodopa (-0.06) compared with after levodopa (0.27); [t (9) = −3.83; p = 0.004]. These results suggest that defective scaling of Stride Length underlies gait disturbance in PD.
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abnormalities in the Stride Length cadence relation in parkinsonian gait
Movement Disorders, 1998Co-Authors: Meg E Morris, Robert Iansek, Thomas A Matyas, Jeffery J SummersAbstract:The purpose of this investigation was to clarify abnormalities in the Stride Length-cadence relation in gait hypokinesia in Parkinson's disease (PD). A second aim was to investigate the effect of levodopa medication on the foot-step pattern. In the first experiment, 20 subjects with idiopathic PD and 20 age-, sex-, and height-matched controls performed a series of 10 m walking trials at cadence rates ranging from 40 steps/min to 180 steps/min. Cadence rates were set by an electronic metronome, and gait patterns were measured by using a footswitch Stride-analyzer system. By instructing subjects to concentrate on walking in time to the metronome beat, the baseline Stride Length could be monitored for a range of velocities with the compensatory effects of cadence removed. Linear-regression analysis revealed that the mean slope for the regression of Stride Length against cadence was not different form normal in PD, although there was a statistically significant difference in mean intercept between the PD group (0.25) and the control group (0.59); [t (19) = −4.76; p = 0.0001]. The second experiment evaluated the effects of levodopa on StrideLength regulation in 10 subjects with idiopathic PD on average 45 min before and after the first morning dose was administred. There was a statistically significant increase in Stride Length for all cadence rates from premedication to postmedication phases and the maximal Stride Length was achieved at higher cadence rates after medication. The slope of the regression of Stride Length against cadence did not alter according to medication status, although the mean intercept was significantly lower before levodopa (-0.06) compared with after levodopa (0.27); [t (9) = −3.83; p = 0.004]. These results suggest that defective scaling of Stride Length underlies gait disturbance in PD.
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Stride Length regulation in parkinson s disease normalization strategies and underlying mechanisms
Brain, 1996Co-Authors: Meg E Morris, Robert Iansek, Thomas A Matyas, Jeffery J SummersAbstract:Summary Results of our previous studies have shown that the slow, shuffling gait of Parkinson's disease patients is due to an inability to generate appropriate Stride Length and that cadence control is intact and is used as a compensatory mechanism. The reason for the reduced Stride Length is unclear, although deficient internal cue production or inadequate contribution to cortical motor set by the basal ganglia are two possible explanations. In this study we have examined the latter possibility by comparing the long-lasting effects of visual cues in improving Stride Length with that of attentional strategies. Computerized Stride analysis was used to measure the spatial (distance) and temporal (timing) parameters of the walking pattern in a total of 54 subjects in three separate studies. In each study Parkinson's disease subjects were trained for 20 min by repeated 10 m walks set at control Stride Length (determined from control subjects matched for age, sex and height), using either visual floor
Mary Danoudis - One of the best experts on this subject based on the ideXlab platform.
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gait in huntington s disease and the Stride Length cadence relationship
BMC Neurology, 2014Co-Authors: Robert Iansek, Mary DanoudisAbstract:The progressive deterioration of gait in Huntington’s disease (HD) leads to functional decline and loss of function. To understand the underlying mechanisms responsible for the gait changes in HD, we examined the automatic control of gait by measuring the relationship between Stride Length and cadence. The relationship is strongly linked in healthy adults during automatic gait but disrupted in pathological gait disorders, such as Parkinson’s disease (PD). The Stride Length cadence relationship was compared between seventeen participants with HD, twenty with PD and twenty one healthy older adults (HOA). Participants had their gait recorded at self-selected preferred, very slow, slow, fast and very fast speeds. Linear regression analysis was used to determine the slope and intercept of the relationship which were compared between groups. The adjustment of Stride Length and cadence when changing gait speeds was measured and compared within and between groups. Linearity was strong in all but two participants with HD and one with PD. Slope did not differ between groups (p > 0.05) but intercept was lower in the HD and PD groups compared to HOA (p 0.05) regardless of speed. The HD group adjusted Stride Length and cadence similar to HOA when changing speed. The range of cadence across speed conditions did not differ between groups. Scaling of Stride Length but not the regulation of cadence was found to be disrupted in participants with HD.
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central gait control mechanisms and the Stride Length cadence relationship
Gait & Posture, 2011Co-Authors: Thorlene Egerton, Mary Danoudis, Frances Huxham, Robert IansekAbstract:Abstract The Stride Length – cadence relationship (SLCrel) was investigated to explore a theory of two alternate but inter-related pathways for gait control. Sixty-three healthy people in three age groups walked along a computerized walkway (GAITRite®) at five self-selected speeds from very slow to very fast, five cadences from 70 to 150 steps/min and five Stride Lengths from 0.8 to 1.6 m. The data points from two walks in each level of each condition were examined for linear and quadratic relationships. In the self-selected speed condition 97% of participants had a positive linear or quadratic relationship of R2 ≥ 0.90. The quadratic relationships showed Stride Length decreased with very high cadences. When walks with cadences above 150 steps/min were removed, 95% of participants had a positive linear relationship of R2 ≥ 0.90. No age-related differences were found in slope or intercept of linear relationships or in maximum, minimum or range of Stride Length or cadence in the self-selected speed condition. In the cadence and Stride Length conditions, only 32% and 14% of positive linear or quadratic relationships were R2 ≥ 0.90. The near-invariant SLCrel, unaffected by ageing that exists for nearly all individuals when walking at self-selected speeds, indicates that the SLCrel may be used to simplify central control of automatic gait in healthy individuals. The current investigation also provides SLCrel data for healthy people which can be compared with patient populations.
Lucas R Nascimento - One of the best experts on this subject based on the ideXlab platform.
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walking training with cueing of cadence improves walking speed and Stride Length after stroke more than walking training alone a systematic review
Journal of Physiotherapy, 2015Co-Authors: Lucas R Nascimento, Camila Quel De Oliveira, Stella Maris Michaelsen, Luci Fuscaldi TeixeirasalmelaAbstract:Abstract Question: After stroke, is walking training with cueing of cadence superior to walking training alone in improving walking speed, Stride Length, cadence and symmetry? Design: Systematic review with meta-analysis of randomised or controlled trials. Participants: Adults who have had a stroke. Intervention: Walking training with cueing of cadence. Outcome measures: Four walking outcomes were of interest: walking speed, Stride Length, cadence and symmetry. Results: This review included seven trials involving 211 participants. Because one trial caused substantial statistical heterogeneity, meta-analyses were conducted with and without this trial. Walking training with cueing of cadence improved walking speed by 0.23 m/s (95% CI 0.18 to 0.27, I 2 =0%), Stride Length by 0.21 m (95% CI 0.14 to 0.28, I 2 =18%), cadence by 19 steps/minute (95% CI 14 to 23, I 2 =40%), and symmetry by 15% (95% CI 3 to 26, random effects) more than walking training alone. Conclusions: This review provides evidence that walking training with cueing of cadence improves walking speed and Stride Length more than walking training alone. It may also produce benefits in terms of cadence and symmetry of walking. The evidence appears strong enough to recommend the addition of 30minutes of cueing of cadence to walking training, four times a week for 4 weeks, in order to improve walking in moderately disabled individuals with stroke. Review Registration: PROSPERO (CRD42013005873). [Nascimento LR, de Oliveira CQ, Ada L, Michaelsen SM, Teixeira-Salmela LF (2015 ) Walking training with cueing of cadence improves walking speed and Stride Length after stroke more than walking training alone: a systematic review. Journal of Physiotherapy 61: 10–15 ]
Dan K Ramsey - One of the best experts on this subject based on the ideXlab platform.
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Effect of Stride Length on overarm throwing delivery: A linear momentum response q,qq
2020Co-Authors: Dan K Ramsey, Ryan L Crotin, Scott C. WhiteAbstract:Changing Stride Length during overhand throwing delivery is thought to alter total body and throwing arm linear momentums, thereby altering the proportion of throwing arm momentum relative to the total body. Using a randomized cross-over design, nineteen pitchers (15 collegiate and 4 high school) were assigned to pitch two simulated 80-pitch games at ±25% of their desired Stride Length. An 8-camera motion capture system (240 Hz) integrated with two force plates (960 Hz) and radar gun tracked each throw. Segmental linear momentums in each plane of motion were summed yielding throwing arm and total body momentums, from which compensation ratio’s (relative contribution between the two) were derived. Pairwise comparisons at hallmark events and phases identified significantly different linear momentum profiles, in particular, anteriorly directed total body, throwing arm, and momentum compensation ratios (P 6 .05) as a result of manipulating Stride Length. Pitchers with shorter Strides generated lower forward (anterior) momentum before Stride foot contact, whereas greater upward and lateral momentum (toward third base) were evident during the acceleration phase. The evidence suggests insufficient total body momentum in the intended throwing direction may potentially influence performance
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Stride Length the impact on propulsion and bracing ground reaction force in overhand throwing
Sports Biomechanics, 2019Co-Authors: Dan K Ramsey, Ryan L CrotinAbstract:Propulsion and bracing ground reaction force (GRF) in overhand throwing are integral in propagating joint reaction kinetics and ball velocity, yet how Stride Length effects drive (hind) and Stride ...
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effect of Stride Length on overarm throwing delivery part ii an angular momentum response
Human Movement Science, 2016Co-Authors: Dan K Ramsey, Ryan L CrotinAbstract:Abstract This is the second component of a two-part series investigating 3D momentum profiles specific to overhand throwing, where altering Stride reportedly influences throwing mechanics resulting in significantly different physiologic outcomes and linear momentum profiles. Using a randomized cross-over design, nineteen pitchers (15 collegiate and 4 high school) were assigned to pitch two simulated 80-pitch games at ±25% of their desired Stride Length. An 8-camera motion capture system (240 Hz) integrated with two force plates (960 Hz) and radar gun tracked each overhand throw. Segmental angular momentums were summed yielding throwing arm and total body momentums, from which compensation ratio’s (relative contribution between the two) were derived. Pairwise comparisons at hallmark events and phases identified significantly different angular momentum profiles, in particular total body, throwing arm, and momentum compensation ratios ( P ⩽ 0.05) as a result of manipulating Stride Length. Sagittal, frontal, and transverse angular momentums were affected by Stride Length changes. Transverse magnitudes showed greatest effects for total body, throwing arm, and momentum compensation ratios. Since the trunk is the main contributor to linear and angular momentum, longer Strides appear to better regulate transverse trunk momentum in double support, whereas shorter Strides show increased momentum prior to throwing arm acceleration.
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an inferential investigation into how Stride Length influences temporal parameters within the baseball pitching delivery
Human Movement Science, 2015Co-Authors: Ryan L Crotin, Shivam Bhan, Dan K RamseyAbstract:Abstract Motion analyses of lower body mechanics offer new schemas to address injury prevention strategies among baseball pitchers, where the influence of Stride Length remains unknown. This study examined the temporal effect of Stride Length at constituent pitching events and phases. Nineteen competitive pitchers (15 collegiate, 4 high school) were randomly assigned to pitch two simulated, 80-pitch games at ±25% of their desired Stride Length. An integrated, three-dimensional motion capture system recorded each pitch. Paired t-tests were used to determine whether differences between Stride conditions at respective events and within phases were significantly different. The results demonstrate the shorter Strides mediated earlier onset of Stride foot contact, reduced time in single support whereas double support intervals increased (p
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effect of Stride Length on overarm throwing delivery a linear momentum response
Human Movement Science, 2014Co-Authors: Dan K Ramsey, Ryan L Crotin, Scott C. WhiteAbstract:Abstract Changing Stride Length during overhand throwing delivery is thought to alter total body and throwing arm linear momentums, thereby altering the proportion of throwing arm momentum relative to the total body. Using a randomized cross-over design, nineteen pitchers (15 collegiate and 4 high school) were assigned to pitch two simulated 80-pitch games at ±25% of their desired Stride Length. An 8-camera motion capture system (240 Hz) integrated with two force plates (960 Hz) and radar gun tracked each throw. Segmental linear momentums in each plane of motion were summed yielding throwing arm and total body momentums, from which compensation ratio’s (relative contribution between the two) were derived. Pairwise comparisons at hallmark events and phases identified significantly different linear momentum profiles, in particular, anteriorly directed total body, throwing arm, and momentum compensation ratios ( P ⩽ .05) as a result of manipulating Stride Length. Pitchers with shorter Strides generated lower forward (anterior) momentum before Stride foot contact, whereas greater upward and lateral momentum (toward third base) were evident during the acceleration phase. The evidence suggests insufficient total body momentum in the intended throwing direction may potentially influence performance (velocity and accuracy) and perhaps precipitate throwing arm injuries.
Jeffery J Summers - One of the best experts on this subject based on the ideXlab platform.
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Abnormalities in the Stride Length‐cadence relation in parkinsonian gait
Movement Disorders, 1998Co-Authors: Meg E Morris, Robert Iansek, Thomas A Matyas, Jeffery J SummersAbstract:The purpose of this investigation was to clarify abnormalities in the Stride Length-cadence relation in gait hypokinesia in Parkinson's disease (PD). A second aim was to investigate the effect of levodopa medication on the foot-step pattern. In the first experiment, 20 subjects with idiopathic PD and 20 age-, sex-, and height-matched controls performed a series of 10 m walking trials at cadence rates ranging from 40 steps/min to 180 steps/min. Cadence rates were set by an electronic metronome, and gait patterns were measured by using a footswitch Stride-analyzer system. By instructing subjects to concentrate on walking in time to the metronome beat, the baseline Stride Length could be monitored for a range of velocities with the compensatory effects of cadence removed. Linear-regression analysis revealed that the mean slope for the regression of Stride Length against cadence was not different form normal in PD, although there was a statistically significant difference in mean intercept between the PD group (0.25) and the control group (0.59); [t (19) = −4.76; p = 0.0001]. The second experiment evaluated the effects of levodopa on StrideLength regulation in 10 subjects with idiopathic PD on average 45 min before and after the first morning dose was administred. There was a statistically significant increase in Stride Length for all cadence rates from premedication to postmedication phases and the maximal Stride Length was achieved at higher cadence rates after medication. The slope of the regression of Stride Length against cadence did not alter according to medication status, although the mean intercept was significantly lower before levodopa (-0.06) compared with after levodopa (0.27); [t (9) = −3.83; p = 0.004]. These results suggest that defective scaling of Stride Length underlies gait disturbance in PD.
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abnormalities in the Stride Length cadence relation in parkinsonian gait
Movement Disorders, 1998Co-Authors: Meg E Morris, Robert Iansek, Thomas A Matyas, Jeffery J SummersAbstract:The purpose of this investigation was to clarify abnormalities in the Stride Length-cadence relation in gait hypokinesia in Parkinson's disease (PD). A second aim was to investigate the effect of levodopa medication on the foot-step pattern. In the first experiment, 20 subjects with idiopathic PD and 20 age-, sex-, and height-matched controls performed a series of 10 m walking trials at cadence rates ranging from 40 steps/min to 180 steps/min. Cadence rates were set by an electronic metronome, and gait patterns were measured by using a footswitch Stride-analyzer system. By instructing subjects to concentrate on walking in time to the metronome beat, the baseline Stride Length could be monitored for a range of velocities with the compensatory effects of cadence removed. Linear-regression analysis revealed that the mean slope for the regression of Stride Length against cadence was not different form normal in PD, although there was a statistically significant difference in mean intercept between the PD group (0.25) and the control group (0.59); [t (19) = −4.76; p = 0.0001]. The second experiment evaluated the effects of levodopa on StrideLength regulation in 10 subjects with idiopathic PD on average 45 min before and after the first morning dose was administred. There was a statistically significant increase in Stride Length for all cadence rates from premedication to postmedication phases and the maximal Stride Length was achieved at higher cadence rates after medication. The slope of the regression of Stride Length against cadence did not alter according to medication status, although the mean intercept was significantly lower before levodopa (-0.06) compared with after levodopa (0.27); [t (9) = −3.83; p = 0.004]. These results suggest that defective scaling of Stride Length underlies gait disturbance in PD.
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Stride Length regulation in parkinson s disease normalization strategies and underlying mechanisms
Brain, 1996Co-Authors: Meg E Morris, Robert Iansek, Thomas A Matyas, Jeffery J SummersAbstract:Summary Results of our previous studies have shown that the slow, shuffling gait of Parkinson's disease patients is due to an inability to generate appropriate Stride Length and that cadence control is intact and is used as a compensatory mechanism. The reason for the reduced Stride Length is unclear, although deficient internal cue production or inadequate contribution to cortical motor set by the basal ganglia are two possible explanations. In this study we have examined the latter possibility by comparing the long-lasting effects of visual cues in improving Stride Length with that of attentional strategies. Computerized Stride analysis was used to measure the spatial (distance) and temporal (timing) parameters of the walking pattern in a total of 54 subjects in three separate studies. In each study Parkinson's disease subjects were trained for 20 min by repeated 10 m walks set at control Stride Length (determined from control subjects matched for age, sex and height), using either visual floor
