Biomechanics Commons^™

Frequency Domain Characteristics Of Ground Reaction Forces During Walking Of Young And Elderly Females, Nikolaos Stergiou, Giannis Giakas, Jennifer E. Byrne, Valerie Pomeroy

Journal Articles

Objective. To examine the frequency domain characteristics of the ground reaction forces of young and elderly females during free walking.

Design. Independent t-tests were used to examine the frequency content of all three components of the ground reaction force.

Background. Frequency domain analysis has the potential to assist in identifying changes in gait that may be masked in the time domain. No research has been done to identify changes in gait due to age-related impairments in the frequency domain.

Methods. Ten young and ten elderly females walked at a prescribed speed while ground reaction forces were collected via a …

Effect Of Normalization And Phase Angle Calculations On Continuous Relative Phase, Max J. Kurza, Nikolaos Stergiou

Journal Articles

The purpose of this investigation was to determine if phase plot normalization and phase angle definitions would have an affect on continuous relative phase calculations. A subject ran on a treadmill while sagittal plane kinematic data were collected with a high­ speed (180Hz) camera. Segmental angular displacements and velocities were used to create phase plots, and examine the coordination between the leg and thigh. Continuous relative phase was calculated with a combination of two different amplitude normalization techniques, and two different phase angle definitions. Differences between the techniques were noted with a root mean square (RMS) calculation. RMS values indicated …

A Motor And A Brake: Two Leg Extensor Muscles Acting At The Same Joint Manage Energy Differently In A Running Insect, Anna N. Ahn, Robert J. Full

All HMC Faculty Publications and Research

The individual muscles of a multiple muscle group at a given joint are often assumed to function synergistically to share the load during locomotion. We examined two leg extensors of a running cockroach to test the hypothesis that leg muscles within an anatomical muscle group necessarily manage (i.e. produce, store, transmit or absorb) energy similarly during running. Using electromyographic and video motion-analysis techniques, we determined that muscles 177c and 179 are both active during the first half of the stance period during muscle shortening. Using the in vivo strain and stimulation patterns determined during running, we measured muscle power output. …

Comparison Of Gait Patterns Between Young And Elderly Women: An Examination Of Coordination, Jennifer E. Byrne, Nikolaos Stergiou, Daniel Blanke, Jeremy J. Houser, Max J. Kurz, Patricia A. Hageman

Journal Articles

This study investigated intralimb coordination during walking in Young and Elderly women using the theoretical model of dynamical systems. Twenty females, ten Young (M age = 24.6 yrs, SD = 3.2 yrs), and ten Elderly (M age = 73.7 yrs, SD = 4.9 yrs), were videotaped during free speed gait and gait perturbed by an ankle weight. Two parameters, one describing the phasing relationship between segments (mean absolute relative phase) and the other the variability of this relationship (deviation in phase), were calculated from the kinematics. Two-way ANOVA (age and weight) with repeated measures on weight indicated that during the …

Foot Strike Patterns After Obstacle Clearance During Running, Shane D. Scholten, Nicholas Stergiou, Alan Hreljac, Jeremy J. Houser, Daniel Blanke, L. Russell Alberts

Journal Articles

Purpose

Running over obstacles of sufficient height requires heel strike (HS) runners to make a transition in landing strategy to a forefoot (FF) strike, resulting in similar ground reaction force patterns to those observed while landing from a jump. Identification of the biomechanical variables that distinguish between the landing strategies may offer some insight into the reasons that the transition occurs. The purpose of this study was to investigate the difference in foot strike patterns and kinetic parameters of heel strike runners between level running and running over obstacles of various heights.

Methods

Ten heel strike subjects ran at their …

A Comparison Of Training Methods To Increase Neck Muscle Strength [Thesis], Ryan Stuart Price

Theses : Honours

The purpose of this study WHS to determine if increases in isometric cervical muscle strength and range of movement (ROM) generated from ten weeks of training on the Multi-cervical unit (MCU) is significantly greater than the increase gained by training with the dynaband. The high rate of neck injury in the Air Force from pilots exposed to high +Gz force has instigated this research. 32 healthy subjects were split into three groups, with one group as the control, one group training on the MCU and one group training on the dynaband. Training groups completed ten weeks of resistance training in …