The Experts below are selected from a list of 327 Experts worldwide ranked by ideXlab platform
Casey D Kerrigan - One of the best experts on this subject based on the ideXlab platform.
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a three dimensional kinematic and kinetic comparison of overground and Treadmill walking in healthy elderly subjects
Clinical Biomechanics, 2010Co-Authors: Jaclyn R Watt, Patrick O Riley, Jason R Franz, Keith Jackson, Jay Dicharry, Casey D KerriganAbstract:Abstract Background Instrumented Treadmills offer a number of advantages for the biomechanical analysis of elderly gait, yet it is unclear how closely Treadmill gait approximates overground gait. Although studies have indicated that the kinematics and kinetics of overground and Treadmill gait are very similar in young adults, it still needs to be determined whether data collected in elderly adults during Treadmill walking can be generalized to overground gait. The purpose of this study, therefore, was to compare the three-dimensional kinematics and kinetics of Treadmill gait to overground gait in a group of healthy elderly subjects. Methods Three-dimensional kinematic and kinetic data for 18 healthy, nondisabled elderly subjects, age 65–81 years, were collected for speed-matched overground and Treadmill walking conditions. Findings Overall, the kinematics and kinetics of gait during Treadmill and overground walking in the elderly had very similar patterns. However, during Treadmill walking elderly subjects showed greater cadence, smaller stride length and stride time as well as reductions in the majority of joint angles, moments and powers when compared to overground walking. Interpretation The large increase in cadence suggests that an effective method of acclimation to Treadmill walking still needs to be determined. Because of the differences, we believe that in order for instrumented Treadmills to become a suitable tool for research and training purposes in healthy elderly, subjects must be adequately acclimated to the Treadmill.
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a kinematics and kinetic comparison of overground and Treadmill running
Medicine and Science in Sports and Exercise, 2008Co-Authors: Patrick O Riley, Ugo Della Croce, Jason R Franz, Jay Dicharry, Robert P Wilder, Casey D KerriganAbstract:RILEY, P. O., J. DICHARRY, J. FRANZ, U. D. CROCE, R. P. WILDER, and D. C. KERRIGAN. A Kinematics and Kinetic Comparison of Overground and Treadmill Running. Med. Sci. Sports Exerc., Vol. 40, No. 6, pp. 1093–1100, 2008. Purpose: The purpose of this study was to compare the kinematic and kinetic parameters of Treadmill running to those of overground running. Methods: Twenty healthy young subjects ran overground at their self-selected moderate running speed. Motion capture and ground reaction force (GRF) data for three strides of each limb were recorded and the subjects_ average running speed was evaluated. The subjects then ran on an instrumented Treadmill set to their average overground running speed while motion capture and GRF data were recorded. The kinematics (body segment orientations and joint angles) and kinetics (net joint moments and joint powers) for Treadmill (15 consecutive gait cycles) and overground running (three cycles each limb) were calculated and compared. Results: The features of the kinematic and kinetic trajectories of Treadmill gait were similar to those of overground gait. Statistically significant differences in knee kinematics, the peak values of GRF, joint moment, and joint power trajectories were identified. Discussion: Parameters measured with an adequate instrumented Treadmill are comparable to but not directly equivalent to those measured for overground running. With such an instrument, it is possible to study the mechanics of running under well-controlled and reproducible conditions. Significance: Treadmill-based analysis of running mechanics can be generalized to overground running mechanics, provided the Treadmill surface is
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a kinematic and kinetic comparison of overground and Treadmill walking in healthy subjects
Gait & Posture, 2007Co-Authors: Patrick O Riley, Gabriele Paolini, Ugo Della Croce, Kate W Paylo, Casey D KerriganAbstract:Introduction: Gait evaluation protocols using instrumented Treadmills will be increasingly used in the near future. For this reason, it must be shown that using instrumented Treadmills will produce measures of the ground reaction force adequate for inverse dynamic analysis, and differences between Treadmill and overground gait must be well characterized. Methods: Overground walking kinetics were estimated with the subjects walking at their self-selected comfortable walking speed. For the Treadmill gait trials, the subjects walked on two Treadmills, such that heel-strike occurred on the forward Treadmill and toe-off occurred on the trailingTreadmill.TheTreadmillwassettotheaverageovergroundwalkingspeed.OvergroundandTreadmilldatawereevaluatedusingViconPluginGait.The differences betweenthe maximaandminimaofkinematic andkineticparametersforovergroundandTreadmillgait wereevaluated. Results: The kinematics of Treadmill and overground gait were very similar. Twelve of 22 kinematic parameter maxima were statistically significantly different (p < 0.05), but the magnitude of the difference was generally less than 28. All GRF maxima were found to be statistically significantly smaller for Treadmill versus overground gait (p < 0.05) as were 15 of 18 moment, and 3 of 6 power maxima. However, the magnitude of the differences was comparable to the variability in normal gait parameters. The sagittal plane ankle moments were not statistically different for Treadmill and overground gait. Discussion: WehaveshownthatTreadmillgaitisqualitativelyandquantitativelysimilartoovergroundgait.Differencesinkinematicandkinetic
Jaap Harlaar - One of the best experts on this subject based on the ideXlab platform.
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Energy exchange between subject and belt during Treadmill walking
Journal of Biomechanics, 2014Co-Authors: Lizeth H. Sloot, M.m. Van Der Krogt, Jaap HarlaarAbstract:Treadmill walking aims to simulate overground walking, but intra-stride belt speed variations of Treadmills result in some interaction between Treadmill and subject, possibly obstructing this aim. Especially in self-paced Treadmill walking, in which the belt speed constantly adjusts to the subject, these interactions might affect the gait pattern significantly. The aim of this study was to quantify the energy exchange between subject and Treadmill, during the fixed speed (FS) and self-paced (SP) modes of Treadmill walking. Eighteen subjects walked on a dual-belt instrumented Treadmill at both modes. The energy exchange was calculated as the integration of the product of the belt speed deviation and the fore-aft ground reaction force over the stride cycle. The total positive energy exchange was 0.44 J/stride and the negative exchange was 0.11 J/stride, which was both less than 1.6% of the performed work on the center of mass. Energy was mainly exchanged from subject to Treadmill during both the braking and propulsive phase of gait. The two Treadmill modes showed a similar pattern of energy exchange, with a slightly increased energy exchange during the braking phase of SP walking. It is concluded that Treadmill walking is only mildly disturbed by subject-belt interactions when using instrumented Treadmills with adequate belt control.
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self paced versus fixed speed Treadmill walking
Gait & Posture, 2013Co-Authors: Lizeth H. Sloot, M M Van Der Krogt, Jaap HarlaarAbstract:Abstract Instrumented Treadmills are increasingly used in gait research, although the imposed walking speed is suggested to affect gait performance. A feedback-controlled Treadmill that allows subjects to walk at their preferred speed, i.e. functioning in a self-paced (SP) mode, might be an attractive alternative, but could disturb gait through accelerations of the belt. We compared SP with fixed speed (FS) Treadmill walking, and also considered various feedback modes. Nineteen healthy subjects walked on a dual-belt instrumented Treadmill. Spatio-temporal, kinematic and kinetic gait parameters were derived from both the average stride patterns and stride-to-stride variability. For 15 out of 70 parameters significant differences were found between SP and FS. These differences were smaller than 1 cm, 1°, 0.2 N m and 0.2 W/kg for respectively stride length and width, joint kinematics, moments and powers. Since this is well within the normal stride variability, these differences were not considered to be clinically relevant, indicating that SP walking is not notably affected by belt accelerations. The long-term components of walking speed variability increased during SP walking (43%, p
Ugo Della Croce - One of the best experts on this subject based on the ideXlab platform.
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a kinematics and kinetic comparison of overground and Treadmill running
Medicine and Science in Sports and Exercise, 2008Co-Authors: Patrick O Riley, Ugo Della Croce, Jason R Franz, Jay Dicharry, Robert P Wilder, Casey D KerriganAbstract:RILEY, P. O., J. DICHARRY, J. FRANZ, U. D. CROCE, R. P. WILDER, and D. C. KERRIGAN. A Kinematics and Kinetic Comparison of Overground and Treadmill Running. Med. Sci. Sports Exerc., Vol. 40, No. 6, pp. 1093–1100, 2008. Purpose: The purpose of this study was to compare the kinematic and kinetic parameters of Treadmill running to those of overground running. Methods: Twenty healthy young subjects ran overground at their self-selected moderate running speed. Motion capture and ground reaction force (GRF) data for three strides of each limb were recorded and the subjects_ average running speed was evaluated. The subjects then ran on an instrumented Treadmill set to their average overground running speed while motion capture and GRF data were recorded. The kinematics (body segment orientations and joint angles) and kinetics (net joint moments and joint powers) for Treadmill (15 consecutive gait cycles) and overground running (three cycles each limb) were calculated and compared. Results: The features of the kinematic and kinetic trajectories of Treadmill gait were similar to those of overground gait. Statistically significant differences in knee kinematics, the peak values of GRF, joint moment, and joint power trajectories were identified. Discussion: Parameters measured with an adequate instrumented Treadmill are comparable to but not directly equivalent to those measured for overground running. With such an instrument, it is possible to study the mechanics of running under well-controlled and reproducible conditions. Significance: Treadmill-based analysis of running mechanics can be generalized to overground running mechanics, provided the Treadmill surface is
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a kinematic and kinetic comparison of overground and Treadmill walking in healthy subjects
Gait & Posture, 2007Co-Authors: Patrick O Riley, Gabriele Paolini, Ugo Della Croce, Kate W Paylo, Casey D KerriganAbstract:Introduction: Gait evaluation protocols using instrumented Treadmills will be increasingly used in the near future. For this reason, it must be shown that using instrumented Treadmills will produce measures of the ground reaction force adequate for inverse dynamic analysis, and differences between Treadmill and overground gait must be well characterized. Methods: Overground walking kinetics were estimated with the subjects walking at their self-selected comfortable walking speed. For the Treadmill gait trials, the subjects walked on two Treadmills, such that heel-strike occurred on the forward Treadmill and toe-off occurred on the trailingTreadmill.TheTreadmillwassettotheaverageovergroundwalkingspeed.OvergroundandTreadmilldatawereevaluatedusingViconPluginGait.The differences betweenthe maximaandminimaofkinematic andkineticparametersforovergroundandTreadmillgait wereevaluated. Results: The kinematics of Treadmill and overground gait were very similar. Twelve of 22 kinematic parameter maxima were statistically significantly different (p < 0.05), but the magnitude of the difference was generally less than 28. All GRF maxima were found to be statistically significantly smaller for Treadmill versus overground gait (p < 0.05) as were 15 of 18 moment, and 3 of 6 power maxima. However, the magnitude of the differences was comparable to the variability in normal gait parameters. The sagittal plane ankle moments were not statistically different for Treadmill and overground gait. Discussion: WehaveshownthatTreadmillgaitisqualitativelyandquantitativelysimilartoovergroundgait.Differencesinkinematicandkinetic
Patrick O Riley - One of the best experts on this subject based on the ideXlab platform.
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a three dimensional kinematic and kinetic comparison of overground and Treadmill walking in healthy elderly subjects
Clinical Biomechanics, 2010Co-Authors: Jaclyn R Watt, Patrick O Riley, Jason R Franz, Keith Jackson, Jay Dicharry, Casey D KerriganAbstract:Abstract Background Instrumented Treadmills offer a number of advantages for the biomechanical analysis of elderly gait, yet it is unclear how closely Treadmill gait approximates overground gait. Although studies have indicated that the kinematics and kinetics of overground and Treadmill gait are very similar in young adults, it still needs to be determined whether data collected in elderly adults during Treadmill walking can be generalized to overground gait. The purpose of this study, therefore, was to compare the three-dimensional kinematics and kinetics of Treadmill gait to overground gait in a group of healthy elderly subjects. Methods Three-dimensional kinematic and kinetic data for 18 healthy, nondisabled elderly subjects, age 65–81 years, were collected for speed-matched overground and Treadmill walking conditions. Findings Overall, the kinematics and kinetics of gait during Treadmill and overground walking in the elderly had very similar patterns. However, during Treadmill walking elderly subjects showed greater cadence, smaller stride length and stride time as well as reductions in the majority of joint angles, moments and powers when compared to overground walking. Interpretation The large increase in cadence suggests that an effective method of acclimation to Treadmill walking still needs to be determined. Because of the differences, we believe that in order for instrumented Treadmills to become a suitable tool for research and training purposes in healthy elderly, subjects must be adequately acclimated to the Treadmill.
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a kinematics and kinetic comparison of overground and Treadmill running
Medicine and Science in Sports and Exercise, 2008Co-Authors: Patrick O Riley, Ugo Della Croce, Jason R Franz, Jay Dicharry, Robert P Wilder, Casey D KerriganAbstract:RILEY, P. O., J. DICHARRY, J. FRANZ, U. D. CROCE, R. P. WILDER, and D. C. KERRIGAN. A Kinematics and Kinetic Comparison of Overground and Treadmill Running. Med. Sci. Sports Exerc., Vol. 40, No. 6, pp. 1093–1100, 2008. Purpose: The purpose of this study was to compare the kinematic and kinetic parameters of Treadmill running to those of overground running. Methods: Twenty healthy young subjects ran overground at their self-selected moderate running speed. Motion capture and ground reaction force (GRF) data for three strides of each limb were recorded and the subjects_ average running speed was evaluated. The subjects then ran on an instrumented Treadmill set to their average overground running speed while motion capture and GRF data were recorded. The kinematics (body segment orientations and joint angles) and kinetics (net joint moments and joint powers) for Treadmill (15 consecutive gait cycles) and overground running (three cycles each limb) were calculated and compared. Results: The features of the kinematic and kinetic trajectories of Treadmill gait were similar to those of overground gait. Statistically significant differences in knee kinematics, the peak values of GRF, joint moment, and joint power trajectories were identified. Discussion: Parameters measured with an adequate instrumented Treadmill are comparable to but not directly equivalent to those measured for overground running. With such an instrument, it is possible to study the mechanics of running under well-controlled and reproducible conditions. Significance: Treadmill-based analysis of running mechanics can be generalized to overground running mechanics, provided the Treadmill surface is
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a kinematic and kinetic comparison of overground and Treadmill walking in healthy subjects
Gait & Posture, 2007Co-Authors: Patrick O Riley, Gabriele Paolini, Ugo Della Croce, Kate W Paylo, Casey D KerriganAbstract:Introduction: Gait evaluation protocols using instrumented Treadmills will be increasingly used in the near future. For this reason, it must be shown that using instrumented Treadmills will produce measures of the ground reaction force adequate for inverse dynamic analysis, and differences between Treadmill and overground gait must be well characterized. Methods: Overground walking kinetics were estimated with the subjects walking at their self-selected comfortable walking speed. For the Treadmill gait trials, the subjects walked on two Treadmills, such that heel-strike occurred on the forward Treadmill and toe-off occurred on the trailingTreadmill.TheTreadmillwassettotheaverageovergroundwalkingspeed.OvergroundandTreadmilldatawereevaluatedusingViconPluginGait.The differences betweenthe maximaandminimaofkinematic andkineticparametersforovergroundandTreadmillgait wereevaluated. Results: The kinematics of Treadmill and overground gait were very similar. Twelve of 22 kinematic parameter maxima were statistically significantly different (p < 0.05), but the magnitude of the difference was generally less than 28. All GRF maxima were found to be statistically significantly smaller for Treadmill versus overground gait (p < 0.05) as were 15 of 18 moment, and 3 of 6 power maxima. However, the magnitude of the differences was comparable to the variability in normal gait parameters. The sagittal plane ankle moments were not statistically different for Treadmill and overground gait. Discussion: WehaveshownthatTreadmillgaitisqualitativelyandquantitativelysimilartoovergroundgait.Differencesinkinematicandkinetic
Lizeth H. Sloot - One of the best experts on this subject based on the ideXlab platform.
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Energy exchange between subject and belt during Treadmill walking
Journal of Biomechanics, 2014Co-Authors: Lizeth H. Sloot, M.m. Van Der Krogt, Jaap HarlaarAbstract:Treadmill walking aims to simulate overground walking, but intra-stride belt speed variations of Treadmills result in some interaction between Treadmill and subject, possibly obstructing this aim. Especially in self-paced Treadmill walking, in which the belt speed constantly adjusts to the subject, these interactions might affect the gait pattern significantly. The aim of this study was to quantify the energy exchange between subject and Treadmill, during the fixed speed (FS) and self-paced (SP) modes of Treadmill walking. Eighteen subjects walked on a dual-belt instrumented Treadmill at both modes. The energy exchange was calculated as the integration of the product of the belt speed deviation and the fore-aft ground reaction force over the stride cycle. The total positive energy exchange was 0.44 J/stride and the negative exchange was 0.11 J/stride, which was both less than 1.6% of the performed work on the center of mass. Energy was mainly exchanged from subject to Treadmill during both the braking and propulsive phase of gait. The two Treadmill modes showed a similar pattern of energy exchange, with a slightly increased energy exchange during the braking phase of SP walking. It is concluded that Treadmill walking is only mildly disturbed by subject-belt interactions when using instrumented Treadmills with adequate belt control.
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self paced versus fixed speed Treadmill walking
Gait & Posture, 2013Co-Authors: Lizeth H. Sloot, M M Van Der Krogt, Jaap HarlaarAbstract:Abstract Instrumented Treadmills are increasingly used in gait research, although the imposed walking speed is suggested to affect gait performance. A feedback-controlled Treadmill that allows subjects to walk at their preferred speed, i.e. functioning in a self-paced (SP) mode, might be an attractive alternative, but could disturb gait through accelerations of the belt. We compared SP with fixed speed (FS) Treadmill walking, and also considered various feedback modes. Nineteen healthy subjects walked on a dual-belt instrumented Treadmill. Spatio-temporal, kinematic and kinetic gait parameters were derived from both the average stride patterns and stride-to-stride variability. For 15 out of 70 parameters significant differences were found between SP and FS. These differences were smaller than 1 cm, 1°, 0.2 N m and 0.2 W/kg for respectively stride length and width, joint kinematics, moments and powers. Since this is well within the normal stride variability, these differences were not considered to be clinically relevant, indicating that SP walking is not notably affected by belt accelerations. The long-term components of walking speed variability increased during SP walking (43%, p
