"Postural Responses to Perturbations in People with Diabetic Peripheral Neuropathy." Becker, M., DeVita, P., Meardon, S., Domire, Z., Kim, S. (2014)
The purposes of this study are to compare the relationships of postural stability measures time-to-contact and center-of-gravity sway area with disease severity in anteroposterior and mediolateral perturbations in people with diabetic neuropathy and to identify the relationships among neuropathic severity and duration with postural stability measure time-to-contact during oblique postural perturbations. 3D Motion capture will be used along with the NeuroCom Research Module balance system. We hypothesize that time-to-contact will provide a more sensitive measure of postural stability for people with diabetic peripheral neuropathy, in regards to all directions of horizontal translational perturbations, as compared to traditional stabilometric measures and that as the severity of neuropathy increases, postural stability in response to horizontal translational perturbations will decrease.
"Joint Torque and Power Redistribution During Accelerated Walking in Older Adults." Rabideau, S., Schuster, D., Bishop, R., Goel, L., Rider, P., Willson, J., DeVita, P. (2014)
The purpose of this study is to compare joint torques and powers between younger (18-25 years old) and older (70-85 years old) adults as they accelerate while walking. A treadmill with a force platform will be used to accelerate participants from 0.5 m/s to 2.0 m/s at three different acceleration rates, 0.3, 0.5, and 0.7 m/s2. Joint torques and powers will be assessed using kinematic data obtained from a 3D motion capture system and the ground reaction forces measured by the force platform. It is expected that older adults will display larger increases in hip torque and power and smaller increases in ankle torque and power compared to younger adults during accelerated walking.
"Effects of Extracellular Matrix in Skeletal Muscle on Mechanotransduction Signaling." Salzano, M., Hibbert, J., Rider, P., Domire, Z. (2014)
The purpose this study is to investigate the effects of muscle stiffness on FAK phosphorylation in rats to find a relationship between stiffness and impaired mechanotransduction signaling. Focal adhesion kinase (FAK) phosphorylation has been implicated in mechanotransduction, the conversion of a mechanical stretch to cellular process, which is important in a muscle's response to exercise. Rats will exercised on one leg on a dynamometer, and subsequently sacrificed, where their dorsiflexors muscles will be tested for stiffness and FAK activity. We hypothesize that increased muscle stiffness with age impairs the mechanotransduction signaling of muscle cells in response to stretch.
"How Do We Accelerate While Running." Schuster, D., Rider, P., Willson, J., DeVita, P. (2014)
The purpose of this study is to quantify lower extremity joint torques and powers during constant speed running and during running while accelerating at three rates of acceleration, 0.40 ms-2, 0.60 ms-2, and 0.80 ms-2 , between a baseline velocity of 2.50 ms-1 to a maximal velocity of 7.00 ms-1. We will use an instrumented treadmill with force transducers and motion capture for gait analysis. The data will then be run through Visual 3D software where the ground reaction forces, joint torques, and joint powers will be calculated using inverse dynamics methods. It is hypothesized that that there will be an increase in the magnitude of the GRFs, joint torques and powers with each step during accelerated running.
"Effect of Eccentric Hamstring Strength Training on Muscle Function." Seymore, K., Hibbert, J., Domire, Z., Kulas, A. (2014)
The purpose of this study is to examine the effects of Nordic Hamstring eccentric strength training on hamstring muscle architecture, stiffness, strength, and dynamic performance. Muscle architecture and stiffness in the biceps femoris long head and semitendinosus will be determined using ultrasound imaging and ultrasound elastography. Vertical jump height with and without a countermovement will be assessed using a Vertec device. Hamstring strength will be measured passively, isometrically, and isokinetically on a HUMAC isokinetic dynamometer. We hypothesize that Nordic Hamstring eccentric strength training will cause adaptations in hamstring muscle architecture, shear modulus, strength, and vertical jump height performance.
"Reliability of Using Ultrasound Technology to Construct Finite Element Foot Models." Bell, E., Rider, P., Kulas, A., Domire, Z. (2014)
The purpose of this study is to assess the reliability of ultrasound technology to develop improved FE models of the foot. 3D ultrasound will be used to measure structural parameters of intrinsic foot muscles and tendons. Ultrasound elastography will be used to measure soft tissue material properties of selected intrinsic foot structures.
"The Relationship Between Muscle Stiffness and Strength in Older Females." Hibbert, J., Rider, P., DeVita, P., & Domire, Z. (2012)
The purpose of this study is to determine if there is a relationship between muscle stiffness and strength in women who are 70 and older. Data are collected using ultrasound elastography to determine what the muscle stiffness is in the vastus lateralis. Maximal Quad strength is measured both isometrically and isokinetically using the HUMAC isokinetic dynamometer.
"The Effects of Quadriceps Strengthening Exercise on Quadriceps Muscle Biomechanics in Adults with Knee Osteoarthritis." Leonardis, J., Rider, P., Aaboe, J., Henriksen, M., Christensen, R., Bliddal, H., & DeVita, P. (2012)
The purpose of this study is to determine the effect of a 12-week quadriceps strengthening program on quadriceps mechanics during level walking, stair ascent, and stair descent in adults with tibio-femoral knee osteoarthritis. This study utilizes a combination of 3D motion capture, ground reaction force, and electromyography data in order to determine any changes to quadriceps muscle force, power, and work during locomotion.
"Improving the Method for Determining Subject-Specific Modeling Parameters." Leonardis, J., Black, J., & Domire, Z. (2012)
The purpose of this practicum study is to determine the number of subject-specific parameters needed to accurately develop a musculoskeletal model. This study uses ultrasound elastography, electromyography, and isokinetic strength data as subject-specific parameters to determine vastus lateralis muscle architecture and moment arms at multiple knee joint angles.
"The Evaluation of Gait Biomechanics as Obesity Increases." Tullock, A.M., Rider, P.,Domire, Z., DeVita, P. (2012).
The purpose of this study is to determine at what point, in relation to the severity of obesity, individuals change their gait pattern to adapt to carrying a heavier load. Data will be collected using 3D Motion Capture for kinematics of gait and a force platform to measure ground reaction forces.
"Biceps Femoris Moment Arm Prediction." Reynolds, K., Rider, P., Kulas, A. (2012)
The purpose of this study is to determine if biceps femoris moment arms can be predicted using anthropometrics alone, measures of muscle architecture, or a combination of both. Data are collected using EMG and ultrasound imaging of the biceps femoris, while subjects are passively moved through a range of motion on a HUMAC isokinetic dynamometer.
"Does Barefoot Running Strengthen the Foot and Thereby Reduce Injury Risk?” Bell, E., Rider, P., Domire, Z., DeVita, P. (2012)
The purpose of this study is to compare the differences in stiffness of the plantar fascia in barefoot and traditionally shod runners using ultrasound elastography. Gait analysis will also be assessed using the 3D Motion Capture system to compare foot striking patterns and running mechanics. We hypothesize that we will see an increased stiffness in the plantar fascia of barefoot runners when compared to traditionally shod runners. We also hypothesize that running mechanics will contribute to the stiffness of the plantar fascia, regardless of footwear.