XXIII ISEK Congress Keynote Speakers

Sunday, July 12

GISELA SJØGAARD, Basmajian Award Lecture
University of Southern Denmark

Gisela Sjøgaard completed M.S. degrees in mathematics and physical education and earned in 1979 her Ph.D and in 1990 her Dr.Med.Sc. in muscle physiology at the University of Copenhagen. She was professor and head of the department of physiology at the National Institute of Occupational Health in Denmark, visiting professor at the University of Guelph, Canada, and at the University of Michigan, USA. She is presently a professor emeritus in Sports and Health Sciences at University of Southern Denmark and a principal investigator at the University of Queensland, Australia and at Zürich University, Switzerland. She has published more than 200 papers in international peer reviewed scientific journals and more than 50 educational publications. She has participated actively with presentations at more than 300 conferences and meetings including more than 100 as invited lecturer. Her main field of competence is human exercise physiology with focus on muscle activation, mechanics, metabolism, and fatigue. Special area of interest is neuromuscular control and muscle biochemistry, as well as their applications to work related musculoskeletal disorders.

The elixir of muscle activation and kinesiology in a health perspective

Basmajian stated in his paper: “The elixir of laughter in rehabilitation” that “everyone advocates cheerfulness on the part of the healing professions” despite lacking evidence. Likewise, evidence was missing of exercise training at the worksite alleviating musculoskeletal pain, although everyone since Hippocrates advocates that physical activity benefits health. Muscle activation and movements performed during work tasks are on the contrary frequently reported to result in work-related musculoskeletal disorders. Therefore, we posed the research question: which mode of muscle activation may result in a reversal of work-related disorders? To address this, we performed electromyographic (EMG) and kinematic assessments of workers with diverse exposure: repetitive monotonous tasks (surgeons, musicians, sewing-machine and computer workers), prolonged  walking/standing (cleaning personnel, meat cutters, and industrial workers) and heavy high intensity loading (military helicopter crew and firefighters). The various job-specific exposure variables could be categorized in terms of duration, intensity, static component, peak force etc. that were subsequently identified as risk factors. Based on sports science principles we developed tailored exercise programs to counteract job exposure overloading. EMG activity during exercise training was monitored to identify principal differences between exercise training and job patterns. Further, we revealed the effects in 17 RCT studies including >3500 workers. We found positive effects as decreased muscle pain and increased workability. Finally, we identified plausible underlying mechanisms in muscle tissue – human and animal – that confirmed metabolic, morphological, and hormonal changes with e.g. repetitive work that were reversal to adaptations reported with exercise training. Progress has been made in developing intelligent physical exercise training as the best complementary activity to job exposure and includes muscle activations and movements that limit work-related inactivity atrophy as well as overload tissue injuries.

Sunday, July 12

DEBORAH FALLA
University of Birmingham

Professor Deborah Falla is Chair in Rehabilitation Science and Physiotherapy at the University of Birmingham, UK and is the Director of the Centre of Precision Rehabilitation for Spinal Pain (CPR Spine). Her research utilises state of the art electrophysiological measures to evaluate the control of human movement and how it is affected or adapted in response to various states (e.g. injury, fatigue, training and pain). She has published over 200 papers in international, peer-reviewed journals and more than 300 conference papers/abstracts including over 30 invited keynote lectures. She has received several recognitions and awards for her work including the German Pain Research Prize in 2014, the George J. Davies – James A. Gould Excellence in Clinical Inquiry Award in 2009 and the Delsys Prize for Electromyography Innovation in 2004. She is an author of three books including the latest entitled “Management of neck pain disorders: a research informed approach” (Elsevier, 2019). Professor Falla is an Associate Editor for Musculoskeletal Science & Practice, the Journal of Electromyography and Kinesiology and IEEE Transactions on Neural Systems and Rehabilitation Engineering. From 2016 to 2018, she was the President of the International Society of Electrophysiology and Kinesiology (ISEK).

Monday, July 13

DARIO FARINA
Imperial College London

Dario Farina received Ph.D. degrees in automatic control and computer science (Ecole Centrale de Nantes) and in electronics and communications engineering (Politecnico di Torino), and an Honorary (Honoris Causa) Doctorate degree in Medicine (Aalborg University). He is currently Full Professor and Chair in Neurorehabilitation Engineering at the Department of Bioengineering of Imperial College London, UK. He has previously been Full Professor at Aalborg University, Aalborg, Denmark, (until 2010) and at the University Medical Center Göttingen, Georg-August University, Germany, where he founded and directed the Department of Neurorehabilitation Systems (2010-2016) and where he was the Chair in Neuroinformatics of the Bernstein Center Neurotechnologies Göttingen. Among other awards, he has been the recipient of the IEEE Engineering in Medicine and Biology Society Early Career Achievement Award (2010), the annual international Brain-Computer Interface Award (2017), the Royal Society Wolfson Research Merit Award (2016), and has been elected Distinguished Lecturer IEEE (2014). His research focuses on biomedical signal processing, neurorehabilitation technology, and neural control of movement. Within these areas, he has (co)-authored ~500 papers in peer-reviewed Journals, which have currently received >30,000 citations. Professor Farina has been the President of ISEK (2012-2014) and is currently the Editor-in-Chief of the official Journal of ISEK, the Journal of Electromyography and Kinesiology. He is also currently an Editor for Science Advances, the Journal of Physiology, IEEE Transactions on Biomedical Engineering, IEEE Transactions on Medical Robotics and Bionics, and Wearable Technologies. Professor Farina has been elected Fellow ISEK, IEEE, AIMBE, and EAMBES.

Tuesday, July 14

JANET TAYLOR
Edith Cowan University

Janet Taylor is a Professor in the School of Medical and Health Sciences at Edith Cowan University and an Honorary Principal Research Scientist at Neuroscience Research Australia. She received her MD in 1991 from the University of New South Wales, Sydney for research in the area of human proprioception. Her continuing research interest is the control of human movement by the nervous system and she has published more than 175 peer reviewed papers in the area. Her work focuses on how the motor pathway changes in response to activity such as stimulation of the brain or nerves, training or practice of motor tasks, and fatiguing exercise. Her aim is to better understand how repetitive activity alters the nervous system in health and disease, and so contributes to improvements in motor performance with practice but to decrements in performance with muscle fatigue. She was a Reviewing and Senior Editor for the Journal of Physiology from 2013 to 2019 and an Associate Editor for Exercise and Sports Science Reviews for 2017-2018.

What is the neuro in neuromuscular fatigue?

Whenever we carry out strenuous, sustained or repetitive physical activity the performance of our motor system progressively declines. Muscle fibres produce less force and the nervous system becomes less able to drive the muscle maximally. Spinal motoneurones are the final neural component in the motor pathway and their firing is the culmination of many processes within the nervous system. Thus, there are multiple mechanisms that can contribute to make motoneurone firing insufficient to generate maximal muscle forces. First, the motoneurones themselves can become less excitable when they fire repetitively. Second, excess serotonin released onto motoneurones via descending fibres from the medulla can act via receptors at the axon initial segment to inhibit motoneurone firing. Conversely, reduced serotonin release during longer duration exercise may hinder the motoneurones’ ability to fire repetitively. Third, sensory feedback from the fatigued muscles, via the small-diameter muscle afferents that fire in response to metabolites, can inhibit some motoneurone pools. Finally, descending drive from the motor cortex to the motoneurones can become suboptimal. Fatigue-related sensory feedback is an important influence on cortical output as well as at a spinal level, and also contributes to the sensations of muscle work, fatigue and pain. The different neural mechanisms of fatigue probably differ in importance with different kinds of exercise, both because they develop at different rates and because they alter task-dependent motor output in different ways. For example, it is easy to see the consequences of fatigue during maximal muscle contractions, when force and power are reduced, whereas during submaximal tasks, compensatory changes in voluntary drive can maintain performance, but this comes at the cost of more effort.

Tuesday, July 14

GLEN LICHTWARK
University of Queensland

Glen Lichtwark is an Associate Professor in the School of Human Movement and Nutrition Sciences, The University of Queensland. He was awarded his PhD from University College London (UK) in December 2005 and has subsequently worked as a postdoctoral fellow at the Royal Veterinary College (UK), Imperial College (UK) and Griffith University, before moving to The University of Queensland in January 2010. A/Prof Lichtwark is particularly interested in how elasticity in muscles and tendons of the lower limb influences the energetics and control of human movement. Since 2003, he has published over 100 peer reviewed articles, including publications in Nature and Proceeding of the National Academy of Science, and was recently awarded a prestigious Future Fellowship from the Australian Research Council. A/Prof Lichtwark’s research has aided in the development of novel new imaging, simulation and measurement techniques to answer fundamental questions about how the body moves, with findings that have application across a broad range of human health and performance areas; including exercise training and prescription, musculoskeletal injury prevention and rehabilitation, and robotic/prosthetic design. Since 2015, Glen has served as a Council Members of the International Council of Biomechanics.

Linking muscle-tendon mechanics to our understanding of human movement control

Textbooks teach the basic anatomical and physiological properties of both muscles and tendons that play a role in governing the limits on human and animal performance. However, the neuromusculosketal system is complex and must also operate within a specific mechanical environment with varying task demands (e.g. force, work, power, precision). Understanding which factors are most important for how we control movement becomes complex in different scenarios. Complex computational models provide valuable tools to better understand the complexity, but a lack of knowledge of the fundamental basis by which the nervous system controls movement, limited information about individual muscle properties of muscles and simplistic models of muscle contraction currently reduce their predictive capacity.

In this presentation, I will outline a program of research that has been aimed towards better understanding the interaction between muscle-tendon mechanics and neural drive required to perform movements (predominantly in the lower limb). I will outline the methods we have used to characterise muscle-tendon mechanical function and provide evidence for the important role that tendinous tissue compliance plays in dictating the control strategies we use for movements. I will also provide specific examples of how characterising muscle-tendon interaction can provide explanations for why muscle excitation patterns are often not easy predict (e.g. when activation levels remain the same or even reduce, despite the force requirements of muscles increasing).

Finally, I will consider some of the current problems and challenges in how we view muscle-tendon mechanics. These challenges need to be overcome to generate accurate models or simulations of movement that can be used to have impact in areas of rehabilitation, sports performance or even prosthetic design. Some of these challenges include how we consider the aponeurosis of the muscle to operate mechanically, heterogeneity in muscle architectural features (including sarcomere length along the muscle) and problems with our current imaging techniques that need to be addressed to provide more accurate experimental data.

Monday, July 13

TETSUO FUKUNAGA
National Institute of Fitness and Sports

Tetsuo Fukunaga received a PhD from The University of Tokyo, Tokyo, Japan, in 1973. He worked as a research assistant in The University of Tokyo from 1971 to 1973; as an associate professor in Chukyo University, Aichi, Japan, from 1973 to 1980; as an associate professor and a full professor at The University of Tokyo, from 1980 to 2002. He then moved to Waseda University, Saitama where he was a full professor from 2002 to 2008. He has served as president of Japanese Society of Biomechanics, and as a council member of the ISB. His research interests include examining muscle-tendon interactions during human movement, often using innovative imaging techniques. He is currently a president of the National Institute of Fitness and Sports in Kanoya, Kagoshima, Japan.

Estimation of mechanical work done during sprint running by means of 50m long force-platform system

Sprint running from a stationary state inevitably involves a period of time until the running velocity reaches the maximum, i.e. the acceleration stage. In this stage, runners are required to maximally accelerate their bodies to attain a high running velocity within a short period. Thus, examining the mechanics of the acceleration stage of maximal sprint running is essential to elucidate how runners are capable of achieving a high power movement. To realize this, it is necessary to continuously obtain data on kinetics and/or kinematics at each step during the entire period of maximal sprint running from the start of the run, because these markedly vary with increasing running velocity (Nagahara et al., 2014, 2018).

Many studies calculated the work done and/or power generated during running by analyzing the ground reaction force (GRF) during the stance period (Cavagna,1975). In previous studies,the work done at every step in running has been divided into two parts on the basis of the horizontal anterior–posterior GRF during the stance period: the work done during the braking phase (negative work) and propulsive phase ( positive work), in which the runner’s body decelerates and accelerates, respectively (Cavagna er al., 1971). The present study aimed to elucidate the magnitude of the mechanical work done in each of the braking and propulsive phases during the acceleration stage of 50 m maximal sprint running and the associations of the work variables with running performance. To this end, we adopted a newly developped 50 m force plate system (Nagahara et al., 2018) to continuously obtain GRFs at every step during the acceleration stage.

At 80% maximum velocity (Vmax) or higher, the positive work largely decreased and negative work abruptly increased. The change in the difference between positive and negative work, namely effective work, for acceleration the body at every step was relatively small at 70% Vmax or lower. Total work done over 50 m was 82.4±7.5 J /kg for positive work, 36.2±4.4 J /kg for negative work. The total effective work over 50 m was more strongly correlated with the running time for 50m (r=−0.946, P<0.0001) than the corresponding associations for the other work variables. These results indicate that in maximal sprint running over 50 m, work done during the propulsive phase in the horizontal anterior–posterior direction accounts for the majority of the total external work done during the acceleration stage, and maximizing it while suppressing work done during the braking phase is essential to achieve a high running performance.

Fukunaga,T., Matsuo, A., Kanehisa, H.

Sunday, July 12

TOSHIO MORITANI
University of Kyoto

Toshio Moritani was born in Japan in 1950. He received his Ph.D. degree in Sports Medicine from the University of Southern California in 1980 under the direction of Dr. Herbert A. deVries. In 1985, following faculty appointments at the University of Texas at Arlington and Texas A&M University, he returned to Japan and joined the Department of Integrated Human Studies at Kyoto University. In 1992, he was appointed as Associate Professor of Applied Physiology at the Graduate School of Human and Environmental Studies at Kyoto University and became Professor since 2000. He has retired from Kyoto University and become Professor Emeritus since 2016. Dr. Moritani has been elected as Fellow of the American College of Sports Medicine. Dr. Moritani was the Editor of the Journal of Electromyography and Kinesiology. Currently Dr. Moritani is the Editor of the European Journal of Applied Physiology. He has also served as one of the Council Members and the Past President of the International Society of Electrophysiology and Kinesiology.

Electrical Muscle Stimulation: Application and potential role in aging society

Neurodegenerative diseases and sarcopenia become more prevalent as individuals age and, therefore, represent a serious issue for the healthcare system. Several studies have reported the relationship between physical activity and reduced incidence of dementia or cognitive deterioration. Thus, exercise and strength training are most recommended treatments, but it is proving difficult to engage individuals to initiate exercise and strength training. Electrical muscle stimulation (EMS) may provide an alternative and more efficient solution. Although EMS has undergone a decline in use, mainly because of stimulation discomfort, new technologies allow painless application of strong contractions. Such activation can be applied in higher exercise dosages and more efficiently than people are likely to achieve with exercise. Unlike orderly recruitment of motor units (MUs) during low intensity voluntary exercise, EMS activates large fast-twitch MUs with glycolytic fibers preferentially and this could have benefit for prevention and treatment of diabetes and chronic diseases associated with muscle atrophy that ultimately lead to bed-ridden conditions. Recent evidence highlights the potential for EMS to make a major impact on these and other lifestyle related diseases and its role as a useful modality for orthopedic and cardiac rehabilitation. This talk will discuss the potential for EMS to break new ground in effective interventions in these frontiers of medical science.