The graduate program in biomechanics studies the physics of human movement with several areas of specialization. In the course of study, students will learn the fundamental methods of analyzing the motion of the body. This will include the quantification of body segment and joint movements by film, video or infrared recording (in two- and three-dimensions), the measurement of external forces acting upon the body by means of force plates, accelerometers, and dynamometers and the collection of measures of muscle activity (electromyographic, or EMG) during movement tasks and subsequent processing. Some work on computer modeling of the musculoskeletal system has also been conducted.
Studied movements include tasks from daily living, to material handling, as well as to elite sport skill performance. One or more of the above methods of analysis may be employed to address specific questions about the mechanics involved in a task (i.e. what are the 'normal' kinematics expected in walking? What mechanical risk factors exist with lifting under different situations? What are the characteristics of elite performance in high jump? How do structural deformities affect joint function?).
Recent research has also used this technology to examine the interrelation of physiological and biomechanical parameters during skating and/or the execution of novel multi-joint movement tasks. With the use of EMG, force and kinematic measures it is possible to examine the interaction of the mechanical and physiological parameters governing the strategic execution of a variety of skills and determine how best to optimize skill execution. This research has been extended to the impact of product modification in ice hockey and its impact performance and fit of ice hockey equipment.
Another area of research at McGill University uses electromyographic, kinematic and kinetic approaches to study the influence of various pathologies such as whiplash injuries and repetitive motion disorders on posture and movement, with applications towards rehabilitation and occupational health and the study musculoskeletal disorders associated with the workplace. Other related research on running, prosthesis and orthotic wear, sports equipment and gait acquisition throughout the lifespan is also underway.
- the physics of human movement (i.e. biomechanics), including tasks from walking and running e.g. the effect of side slopes – such as with the indoor track – on rear foot motion and upper body posture/balance; the effect of fatigue on lower limb kinematics / in shoe loading dynamics / electromyography (EMG) recruitment changes during long distance running; measurement of fore-rear foot torsion during running) and the unique context of locomotion on ice i.e. skating in ice hockey (e.g. the relation of ice hockey performance and design issues related to the skate such as : in boot rear foot kinematics using goniometers; in boot pressure patterns during various skating tasks; measurement of muscle activation patterns using EMG during skating, and
- the impact tolerances of the human body e.g. ice hockey helmet impact performance with aging and use; global dynamic pressure measures between helmet and head during impact; computer modeling of impact behavior of helmets; effect of foam densities and geometries on impact distribution; and impact distribution to soft tissues of the upper and lower limbs.
Clinical exercise physiology
The major objective of this research program is to advance knowledge on the physiology and pathophysiology of chronic respiratory, circulatory or skeletal muscle disorders. Research involves cross-disciplinary collaboration with respirologists, epidemiologists and basic scientists to advance knowledge on exercise intolerance, mechanism of disease and the role of exercise interventions in the clinical management of individuals with chronic respiratory diseases.
Current research projects target the energy demands of physical activities of daily life in patients with various degrees of chronic obstructive lung disease including circulatory - respiratory physiological interactions as limiting factors for peripheral oxygen delivery and skeletal muscle oxygen utilization in the exercise intolerance of these patients.
Other research focuses on the pathophysiology of skeletal muscle mitochondrial disorders and the safety and efficacy of exercise training in their treatment. Deleterious effects of physical inactivity superimposed upon impaired mitochondrial function contribute to varying degrees of exercise intolerance in these patients. Endurance exercise has potential to induce normal adaptive mitochondrial biogenesis thereby increasing levels of functional mitochondria, exercise tolerance and quality of life. The therapeutic potential of resistance training is based on a concept of gene shifting and relies on activation of muscle satellite cells to increase levels of functional muscle mitochondria.
Integrative methodologies in the laboratory including clinical exercise testing and gas exchange, MRI and spectroscopy, ultrasound and NIR, biochemical and molecular analyses are used to measure cardiovascular, pulmonary, metabolic and muscle responses to exercise and training. The idea that mitochondrial dysfunction may be central to aging and other chronic conditions make these ‘cellular powerhouses’ an energizing field of study.
In the muscle physiology field, investigations into the molecular and cellular mechanisms of muscle contraction and force generation are currently being explored. Studies are performed at different levels of analysis, ranging from whole muscles to myofibrils and single molecules. Specific topics under investigation are the effects of length and mechanical strain on the force produced by muscles, and the contribution of different molecules to force generation at the microscopic scale, especially myosin, actin and titin molecules. In the near future, studies looking into sub-cellular properties of muscles affected by diseases (e.g. muscle dystrophy, familial hypertrophic cardiomyopathy) will also be conducted.
Motor Control and Learning
Humans are unique among animals, as when standing erect, they have to maintain a bipedal stance over a narrow support base, provided by the feet. In the standing position, reaching out to touch or grasp an object involves a complex series of adjustments, not only to balance, but also to the trajectory of the limb in order to successfully and accurately attain the target. Such everyday tasks are taken for granted by able-bodied individuals, but often represent a source of destabilization, leading to falls or injury in the elderly or disabled population. Reaching and grasping result in internal forces being imposed upon linked segments, so humans must compensate for segment inertia and gravity when they are standing. The central nervous system is required to estimate the upcoming perturbation and account for it in the production of its motor commands for balance and movement.
The major focus of the research in our Department is to better understand how central nervous commands produced to maintain balance interact with those controlling voluntary movements. The fundamental knowledge gained through our experiments will be used to elucidate problems with balance demonstrated by the elderly, or persons with various pathologies during voluntary movement.
The Balance and Voluntary Movement lab is soon to be equipped with a variety of techniques for studying the underlying principles of Motor Control and Learning. Together, they will provide us with a global picture of human behaviour. The techniques include:
- a state-of-art custom-built servo-driven platform for studying postural responses to unexpected perturbations to balance,
- a custom-built multi-target array for studying arm reaching movements,
- a 6-camera optoelectronic movement measuring system (Vicon) for recording bilateral whole body kinematics,
- 16 channels of electromyography (EMG) for measuring the electrical activity of the muscles,
- 2 Bertec multi-axis force platforms,
- and a treadmill for studying locomotion.
In the future it is hoped that the laboratory will also have the equipment necessary to study visual contributions to postural control during voluntary movement (gaze).