Neuromuscular Mechanics Laboratory

Within the Neuromuscular Mechanics Laboratory we study the mechanical outputs from muscles. Current studies cover a range of areas. We investigate the recruitment of motor units within a muscle and the coordination of activity between muscles, and how these parameters influence the force, power and efficiency of the muscles and limbs. We additionally study muscle architecture, and in particular the paths that the muscle fascicles follow through the muscle bellies, and how these change during contraction. When muscles contract they bulge, the fascicles curve, and the fascicles may change length at different rates from the muscle belly: all these factors influence the force and power that the muscle can produce. These muscle properties are studied through both experimental and theoretical approaches, and we have developed new techniques for EMG signal processing, ultrasound image analysis and computational muscle modelling. Current projects are examining both the fundamental aspects of muscle contraction, as applications in retraining muscle coordination for spinal cord injured patients, and deterioration of muscle performance in the elderly.

The quality of the work that we do is a reflection of the skills, imagination and dedication of the individuals that contribute to the lab. The following people have greatly contributed over the years to this research:

  • Meghan Jackman is studying for her directed studies in 2011. Meghan is using ultrasound imaging to investigate how the architecture of the muscle fascicles changes during dynamic contractions.
  • Avleen Randhawa joined the lab in 2010 to study for her MSc. Avleen is investigating whether changes in muscle structure that occur with sarcopenia in the elderly can explain the loss in force and power output from muscles in the elderly.
  • Erika Harder is doing her second directed studies project with the lab, and she is studying the muscle co-contractions that occur during walking, with the aim to see if we can detect improvements in spinal cord injury patients after rehabilitation.
  • Mischa Harris is a visiting graduate student from UBC who is doing a directed studies project to learn about various EMG techniques. Mischa is investigating whether verbal instructions can be used to influence muscle coordination during a stepping task.
  • Ana Namburette worked as a co-op student in the lab in 2010, and stayed on to do her honors thesis there. Ana has developed methods for quantifying the curvature of muscle fascicles that can be visualized in ultrasound images.
  • Sabrina Lee has been working as a post-doctoral researcher in the lab since 2009, and is studying how the recruitment of different types of motor unit affects the force and power output from muscle. This study involves both considerable experimental and computational aspects, and aims to reconcile our theoretical treatment of muscles with the physiological realities.
  • Kate Potter visited the lab in 2009, and returned in 2010 to work as a research assistant. Kate has been developing some computational models of muscle, and assisting in the finite-element project.
  • Hadi Rahemi started his PhD studies in the lab in 2009, and is currently using finite element models to investigate how the structural properties of muscle affect the force and power output.
  • Karen Forsman joined the lab with an NSERC scholarship in 2009, and then completed a directed studies project there. Karen investigated how EMG properties were influenced by muscle structure.
  • Iris Wong worked first as a volunteer then on a co-op placement in 2009 and measured the changes in muscle and tendon structure during cycling with a diagnostic ultrasound.
  • Ollie Blake, joined the lab in 2008 to study for his MSc. Ollie has quantified how muscle coordination during cycling affects both power output and efficiency and shown that maximum power output and efficiency can not be achieved at the same time. Ollie has been measuring these effects both for indoor tests, and for outdoor time-trial courses.
  • Manku Rana is studying for her PhD. She joined the lab in 2008 and is studying the changes in 3D muscle fascicle architecture that occur during voluntary contractions. She has developed techniques to automatically quantify fascicle orientations from ultrasound images, and is applying these to muscle contractions in man.
  • Through collaboration in both the UK and Canada, Liping Qi characterized both acoustic (AMG) and electrical (EMG) signals from the upper extremity muscles during wheel-chair propulsion. Liping completed her PhD in 2010 and is currently working as a post-doc at the Faculty of Rehabilitative Medicine at the University of Alberta.
  • Henry Chan worked in the lab both on co-op placements and for an undergraduate directed studies. He helped characterize the patterns of muscle co-ordination during walking, and identify how such patterns adapt to weight-assisted treadmill training.
  • Mohammad Abu-Laila did a 6-month work placement in the lab (2007-2008) as part of the co-operative education on his engineering course in which he helped develop a servo-controlled muscle motor.
  • Berna Salman joined the lab in 2008 when her principal supervisor took a position in Montreal. Berna completed her MSc. thesis looking into the effects of robotic-assisted rehabilitation for recovering hand function in stroke patients.
  • Tamara Horn visited for a 3-month practicum (2007-2008) from ETH Zurich. She studied the muscle coordination that occurs during cycling against different mechanical loads, and demonstrated that the co-ordination patterns are load and velocity dependent.
  • Through a series of collaborations since 2007 Josef Kroell is investigating muscle recruitment during alpine skiing, and in particular how motor unit recruitment changes for sustained exercise. Josef completed his PhD at the Institute for Sports Science at Salzburg University in 2010.
  • Pattama Ritruechai studied for her PhD (2005-2009) on the biomechanics of the equine back. Pattama made detailed measurements of the 3D muscle architecture in the longissimus dorsi, and investigated how activity in compartments within this muscle depended on gait, and turning manoeuvres. Pattama left for a faculty position in the Faculty of Veterinary Science, Mahidol University, Thailand.
  • My first official PhD. student was Emma Hodson-Tole (2004-2007). Emma studied the mechanical determinates of motor unit recruitment in the rat and helped develop the EMG analysis techniques. She demonstrated that strategies of recruitment in the rat were similar to those we had recorded during cycling in man. Emma was a finalist at the SEB 2007 conference for this work. Emma left to do Post-doctoral research at Georgia Institute of Technology.
  • As part of the MSc in Veterinary Physiotherapy program at the Royal Veterinary College we investigated a number of treatment and training modalities on equine muscle function (2005-2007). Sarah Price and Kate Barnett investigated the effect of manipulative therapy on the equine back, Joelle Steyt investigated the role of proprioception on gait, Suzanne Cottriall studied the effect of training aids on the longissimus dorsi activity at lunge and Sarah Dalton investigated regional differences in function in the longissimus dorsi muscle.
  • Katrin Uehli visited from ETH in Zurich to study for a diploma in 2005. She used ultrasonography to measure muscle fascicle strain rates during cycling and this formed part of a study that showed a mechanical association between muscle fascicle strain rates and the type of motor unit recruited for cyclic contractions.
  • Prism Schneider visited the group in the UK in the summer of 2004 and collected the data at the Royal National Orthopaedic Hospital for her PhD. She designed Ankle Foot Orthoses with computer controlled variable stiffness and we investigated how the lower extremities adapted to different AFO stiffness. As part of this work Prism was awarded the Delsys Prize for Innovation in Electromyography at the ISB conference in 2005.
  • Antra Rozitis assisted on a number of projects involving a muscle vibrations, EMG analysis and motor recruitment as part of her graduate studies.
  • Anna-Maria Liphardt visited from the German Sport University in Cologne to study for a 6-month diploma in 2002. She studied how the lower extremity muscles damp vibrations that are induced by the heel-strike impact when we walk. She was later a finalist at the ECSS 2003 conference for this work.
  • Marty Smets studied for a summer studentship with us in 2001. He piloted the first of a series of studies that used dynamometers to alter the mechanical demands on the lower extremities in order to force changes in motor recruitment patterns.
  • I first met Gen Temple when she was studying for her PhD in St. Andrews, but she then assisted our studies in 2001 with her muscle fibre histochemistry. This work showed that the spectral properties of an EMG signal are related to the fibre-type of the active muscle rather to the muscle fibre diameter per se.
  • Silvia Pascual studied how muscle activity during running adapts to changes in shoe midsole materials for her honours thesis (2001). We particularly thank our long suffering subjects who repeatedly ran many kilometers for us in the name of science.
  • Kirsty Kemp was our first research assistant in the group (1998-1999) who displayed great patience in preparing bundles of muscle fibres from fish and measuring their contractile properties on a muscle motor. This work led to us develop a model that related fish swimming performance to the intrinsic properties of the muscles and the temperature of the water in which the fish swam.