"A Biomechanical and Metabolic Comparison of Skipping and Running.” McDonnell, J., DeVita, P. (2016)
Locomotion comparison between skipping and running gaits. It appears that skipping may provide greater aerobic and cardiovascular training than running and it may provide this benefit while creating lower skeletal loads than running. Hmmm, that’s pretty interesting. We are comparing locomotion biomechanics including knee and Achilles tendon loads and metabolic cost while skipping and running at the same speed. Suppose skipping were to have these advantages? We wonder if people would incorporate some amount of skipping in their total training program. Interesting idea.
"The Effect of Running Speed on Cumulative Loads Over a Standardized Distance.” DeVita, P., Murphy, K. (2015)
We hypothesize that due to the longer strides and therefore fewer ground contacts in faster vs. slower running that cumulative, summed loads over a standard distance (e.g. one km) would be lower as running speed increases. The purpose of this study is to compare lower extremity biomechanics including knee joint and Achilles tendon during running at three speeds on a per step and a per km basis. The per km basis represents the summed loads. These ideas lead us to change our view of running and running analyses. We also propose that running should be considered as a series of thousands of steps and not single steps performed over a force platform. We wonder what instrumentation advances will occur in the coming years that will enable us to well-measure series of hundreds or even thousands of steps.
"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.