Changes in Muscle Morphology, Neuromuscular Capacity and Tendon Function with Training: Implications for Athletic Performance, Patient Rehabilitation and Aging Individuals
Per Aagaard, University of Southern Denmark, Denmark
Assessment and Development of Human Strength and Power
Robert Usher Newton, Edith Cowan University, Australia
How do Swimmers Control their Front Crawl Swimming Velocity?
Hideki Takagi, University of Tsukuba, Japan
Changes in Muscle Morphology, Neuromuscular Capacity and Tendon Function with Training: Implications for Athletic Performance, Patient Rehabilitation and Aging Individuals
Per Aagaard
University of Southern Denmark
Denmark
Brief Bio
Per Aagaard is professor in Biomechanics at the Muscle Physiology and Biomechanics Research Unit, Department of Sports Science and Clinical Biomechanics, Faculty of health Science, University of Southern Denmark. His research activities are focused on adaptive changes in neuromuscular function and muscle morphology/architecture induced by training at young and old age, neuromuscular and biomechanical aspects of ACL injury, exercise based rehabilitation and prevention of tendinopathy and muscle overuse injury, effects of resistance training on musculoskeletal health.
Abstract
Resistance training is well known to induce adaptive changes in the morphology and architecture of human skeletal muscle, while also leading to adaptive changes in nervous system function (Aagaard 2003, Aagaard et al. 2020). These changes contribute to the marked increase in maximal contractile muscle force and power that can be seen with resistance (strength) training not only in athletes but also in previously untrained persons, including frail and very old (>80 yrs) adults and patients. Importantly, the training induced improvements in skeletal muscle size/architecture and neuromuscular function are translated into improved athletic performance in younger adults, while correspondingly leading to an enhanced functional capacity during activities of daily living in aging individuals and patients, respectively.
Assessment and Development of Human Strength and Power
Robert Usher Newton
Edith Cowan University
Australia
Brief Bio
Dr Robert Newton is a Professor at Edith Cowan University, Perth, Western Australia. Professor Newton has published over 900 scientific papers including 445 refereed scientific journal articles and three books and has a current Scopus h-Index of 82 with his work being cited over 22,500 times. Professor Newton is an Accredited Exercise Physiologist, Certified Strength and Conditioning Specialist, Fellow of the American College of Sports Medicine, Fellow of the National Strength and Conditioning Association and Fellow of Exercise and Sports Science Australia. In 2019, he was named the Western Australian Premier’s Scientist of the Year and in 2021 he was award a higher doctorate (DSc) from the University of Queensland for his research in exercise science. Professor Newton has been a consultant to US Ski and Snowboard, Chicago Bulls, New Jersey Nets, England Rugby, and to name just a few.
Abstract
High velocity of takeoff, release or impact is the primary outcome dictating performance in a wide range of sports requiring sprinting, jumping, throwing, kicking or striking. The physiological, neural and biomechanical mechanisms which combine to produce large impulse are as fascinating as they are complex. The optimal development of these mechanisms through appropriate training requires intelligent and methodical application of current scientific knowledge combined with the skills and insights of the coach and athlete to peak performance for critical competitions while maximising resilience and career longevity. In this paper we will discuss what we believe to be the most impactful mechanisms underlying very powerful human movement and provide insight into training program design so as to optimise strength and power qualities with greatest training efficiency while realistically accommodating time constraints and recovery requirements of the modern elite athlete.
How do Swimmers Control their Front Crawl Swimming Velocity?
Hideki Takagi
University of Tsukuba
Japan
Brief Bio
Hideki Takagi is a Professor at the Faculty of Health and Sport Sciences, University of Tsukuba. He specializes in fluid engineering, biomechanics, and sports engineering, and has published extensively in these fields, especially in swimming and water polo. He is also involved in the development of high functional swimwear, and a swimmer wearing a swimsuit co-developed by him won a gold medal at the Tokyo Olympics. He has also been active as a water polo player and has served as the head coach of the Japanese men's national water polo team.
Abstract
In this lecture, I will present what we know so far about the biomechanics or hydrodynamics of front crawl, focusing on propulsive and resistive forces at different speeds. Recent studies show that the resistive force increases in proportion to the cube of the velocity, which implies that a proficient technique to miminise the resistive (and maximise the propulsive) force is particularly important in sprinters. To increase the velocity in races, swimmers increase their stroke frequency. However, experimental and simulation studies have revealed that there is a maximum frequency beyond which swimmers cannot further increase swimming velocity due to a change in the angle of attack of the hand that reduces its propulsive force. While the results of experimental and simulation studies are consistent regarding the effect of the arm actions on propulsion, the findings of investigations into the effect of the kicking motion are conflicting. Some studies have indicated a positive effect of kicking on propulsion at high swimming velocities while the others have yielded the opposite result. Therefore, in this lecture, I would like to integrate the results of previous studies and explain how swimmers control their swimming speed from various perspectives.