Life Sciences Commons^™

A Common Neural Substrate For The Control Of Anticipatory And Compensatory Postural Responses, Paul Stapley, Benedicte Schepens, Trevor Drew

Dr Paul J Stapley

We have shown previously that reticulospinal neurones (RSNs) in the brainstem pontomedullary reticular formation (PMRF) contribute to the production of the anticipatory postural adjustments (APAs) that precede reaching movements executed in a standing pOSition (Schepens and Drew, 2004, 2006; Schepens, Stapley and Drew, 2008). More recently (Stapley and Drew, 2009), we have also shown that cells in the PMRF contribute to the production of the compensatory responses that are produced by unexpected perturbations (drops) of the support surface from under one paw during quiet stance. In this poster we address the question of whether the same cells in the PMRF …

Reaching To Multiple Targets When Standing: The Spatial Organization Of Feedforward Postural Adjustments, Julia Leonard, Ryan Brown, Paul Stapley

Dr Paul J Stapley

We examined the spatial organization of feedforward postural adjustments produced prior to and during voluntary arm reaching movements executed while standing. We sought to investigate whether the activity of postural muscles before and during reaching was directionally tuned and whether a strategy of horizontal force constraint could be observed. To this end, eight human subjects executed self-paced reach-to-point movements on the random illumination of one of 13 light targets placed within a 180° array centered along the midline of the body. Analysis was divided into two periods: a first corresponding to the 250 ms preceding the onset of the reaching …

Differences In Gender And Performance In Off-Road Triathlon, Romuald Lepers, Paul Stapley

Dr Paul J Stapley

The aims of this study were: (1) to examine performance trends and compare elite male and female athletes at the off-road triathlon (1.5-km swim, 30-km mountain biking, and 11-km trail running) world championships since its inception in 1996, and (2) to compare gender-related differences between off-road triathlon and conventional road-based triathlon. Linear regression analyses and ANOVA were used to examine performance trends and differences between the sexes. Elite male performance times stabilized over the 2005-2009 period, whereas elite female performance times continued to improve, especially for the run leg. Differences in performance times between the sexes were less marked in …

Posture Control During Online Corrections Of Arm Movements Is Predictive, Julia Leonard, Paul Stapley

Dr Paul J Stapley

The control of reaching to a target in standing involves the feed-forward programming of associated postural adjustments (a PAs) that decelerate the body and arm toward the target (Leonard et ai, 2009). However, little is known about the control of aPAs in situations where the final position of the target goal shifts after the reach movement has been initiated. We hypothesized that a predictive reprogramming of the aPA would occur prior to the adjustment of the arm movement to ensure correct execution of the reaching movement. Using a double step paradigm, we investigated the postural adjustments in standing humans exposed …

Independent Control Of Limb Force Underlies Stability During Voluntary Head Movements In Standing Humans, Paul Stapley, Alicia Hilderley, Julia Leonard

Dr Paul J Stapley

Postural stability during voluntary head movements is maintained through the integration of vestibular and neck afferent inputs. These inputs combine to accurately estimate trunk position in space, relative to a turning head. In animals, a loss of vestibular information leads to an active destabilization of balance as neck afferent information is interpreted as a movement of the trunk under a stable head (Stapley et al. 2006).

Postural Adjustments For Online Corrections Of Arm Movements In Standing Humans, Julia Leonard, Valeriya Gritsenko, Ryan Ouckama, Paul Stapley

Dr Paul J Stapley

The aim of this study was to investigate how humans correct ongoing arm movements while standing. Specifically, we sought to understand whether the postural adjustments in the legs required for online corrections of arm movements are predictive or rely on feedback from the moving limb. To answer this question we measured online corrections in arm and leg muscles during pointing movements while standing. Nine health right-handed subjects reached with their dominant arm to a visual target in front of them and aligned with their midline. In some trials, the position of the target would switch from the central target to …

Equilibrium Constraints But Not Joint Constraints Determine Hand Trajectory Planning, C Paizis, C Papaxanthis, P Stapley, T Pozzo

Dr Paul J Stapley

Introduction: Equilibrium constraints play a major role in finger trajectory formation and curved hand paths seem to be the result of a strong coupling between postural and focal task components. However, such curvatures might also result from joint constraints. To test this hyputhesis we investigated the elrect of imposed joint strategies and support conditions on hand trajectory formation during a pointing task beyond arm's length.

Neuromuscular Control And Exercise-Related Leg Pain In Triathletes, Andrew Chapman, Paul Hodges, Andrew Briggs, Paul Stapley, Bill Vicenzino

Dr Paul J Stapley

Previous studies have shown that cycling can directly influence neuromuscular control during subsequent running in some highly trained triathletes. A relationship between this altered neuromuscular control of running and musculoskeletal pain and injury has been proposed; however, this link has not been investigated. PURPOSE: This study aimed to evaluate the influence of cycling on neuromuscular control during subsequent running in highly trained triathletes with and without exercise-related leg pain (ERLP). METHODS: Participants were 34 highly trained triathletes: 10 triathletes with a history of ERLP and 24 training-matched control triathletes with no history of ERLP. Knee and ankle kinematics and leg …

Neurons In The Pontomedullary Reticular Formation Signal Posture And Movement Both As An Integrated Behavior And Independently, Benedicte Schepens, Paul Stapley, Trevor Drew

Dr Paul J Stapley

We have previously suggested that the discharge characteristics of some neurons in the pontomedullary reticular formation (PMRF) are contingent on the simultaneous requirement for activity in both ipsilateral flexor muscles and contralateral extensors. To test this hypothesis we trained cats to stand on four force platforms and to perform a task in which they were required to reach forward with one forelimb or the other and depress a lever. As such the task required the cat to make a flexion movement followed by an extension in the reaching limb while maintaining postural support by increasing extensor muscle tonus in the …

Co-Active Coaching As An Intervention For Obesity Among Female University Students, Melissa Van Zandvoort, Jennifer Irwin, Don Morrow

Donald Morrow

Purpose: The purpose of this study was to assess the impact of Co-active coaching on obese female university students’ body mass index (BMI), waist circumference (WC), functional health status and self-esteem, and conjointly to identify the coaching skills and primary agenda topics that facilitate coaching’s efficacy as an intervention for obesity.

Design: A multiple-baseline, single-subject research design was utilized.Methods: Two certified coaches provided an average of nine, 35-minute, one-on-one sessions with five students whose BMI?30kg/m2 (obesity threshold). Measures included BMI, WC, the Short-Form 36 (SF-36) Health Survey, and the Rosenberg Self-Esteem Scale. Visual inspection was used to analyze changes in …

The Quantitative Assessment Of Motivational Interviewing Using Co-Active Life Coaching Skills As A Treatment For Adults Struggling With Obesity, Courtney Newnham-Kanas, Jennifer Irwin, Don Morrow, Danielle Battram

Donald Morrow

No abstract provided.

The Change Program: Comparing An Interactive Vs Prescriptive Approach To Self-Management Among University Students With Obesity, Don Morrow, Erin Pearson, Irwin Jennifer, Battram Danielle, Melling James

Donald Morrow

No abstract provided.

Sport In Canada: A History, Don Morrow, Kevin Wamsley

Donald Morrow

No abstract provided.

Hyaluronic Acid Based Self-Assembling Nanosystems For Cd44 Target Mediated Sirna Delivery To Solid Tumors., Arun Iyer

Arun Iyer

Anticancer therapeutics employing RNA interference mechanism holds promising potentials for sequence-specific silencing of target genes. However targeted delivery of siRNAs to tumor tissues and cells and more importantly, their intracellular release at sites of interest still remains a major challenge that needs to be addressed before this technique could become a clinically viable option. In the current study, we have engineered and screened a series of CD44 targeting hyaluronic acid (HA) based self-assembling nanosystems for targeted siRNA delivery. The HA polymer was functionalized with lipids of varying carbon chain lengths/nitrogen content, as well as polyamines for assessing siRNA encapsulation. From …