UWOMJ Volume 67, Number 2, Summer 1998

Schulich School of Medicine & Dentistryhttps://ir.lib.uwo.ca/uwomj/1244/thumbnail.jp

Martial Arts for Health: Translating Research into Practice

Fulltext in: http://www.esciencecentral.org/ebooks/martial-arts-for-health/pdf/martial-arts-for-health.pd

Injury and Skeletal Biomechanics

This book covers many aspects of Injury and Skeletal Biomechanics. As the title represents, the aspects of force, motion, kinetics, kinematics, deformation, stress and strain are examined in a range of topics such as human muscles and skeleton, gait, injury and risk assessment under given situations. Topics range from image processing to articular cartilage biomechanical behavior, gait behavior under different scenarios, and training, to musculoskeletal and injury biomechanics modeling and risk assessment to motion preservation. This book, together with "Human Musculoskeletal Biomechanics", is available for free download to students and instructors who may find it suitable to develop new graduate level courses and undergraduate teaching in biomechanics

Determining impact intensities in contact sports

Most sports Personal Protective Equipment (PPE) consist of varying levels of foam – more foam equals more protection. This has led to bulky, cumbersome PPE which restricts user movement. However, before existing PPE can be modified, their performance must be assessed and a baseline for necessary protection must be explicitly determined. This is a major limitation since current techniques for assessing PPE performance and impact intensity measurements from sport have used surrogate anvils and impactors which were not validated for the sports-related impact they tried to replicate. Through a series of independent studies, a better understanding of human impact response in sporting impacts was sought. This included investigating methods for improving the measurement of impact intensities in sports and the assessment of PPE performance. Human impact response revealed that tensed muscle led to a significant increase in impact force but was associated with less perceived discomfort. At low impact intensities common to sport, the increased local stiffness helped to dissipate impact energy and reduce soft tissue compression. As previous anvils omitted this soft tissue response, modifications were made to a martial arts dummy, BOBXL, to increase its biofidelity. This anvil was validated using in vivo kicks and an impact force – impact velocity relationship. Using this validated anvil, existing methods of assessing PPE performance were evaluated. Current methods were found to create artificially comparable levels of force but did so by using an incorrect effective mass and impact velocity. In all tests, PPE performance was found to depend on weight providing evidence of the ‘more protection, more foam’ concept. As it is impractical to use in vivo kicks to assess PPE performance, kick kinematics were investigated to assess its variability in terms of the impact force – impact velocity relationship and its accuracy. This aided in the development of a mechanical kicking robot which could more properly assess PPE performance. This research was applied to the design of form-fitting, impact-mitigating sports PPE with the capability for integrated technology. Proposed amendments to the current methods of assessing PPE will help to develop better testing and better performing PPE in the future

Hip and knee joints biomechanics of karate players during training and competition style kicks

There is an oddity in the long-term practice of Karate as traditionally it has been an activity that can last a lifetime, but there are many people who suffer from various chronic complaints of the lower limbs. Much research has looked at acute injuries in Karate but for the most part these injuries are not to the parts of the body that suffer the chronic problems, from this it would seem likely that chronic injuries are due to repetitive training or from minor non-contact injuries repeated intermittently.The purpose of study is to analyse the main five karate kicks (Front kick, Roundhouse kick, Side kick, Hook kick and Back kick) in three modes (Training, Competition and Competition step). 3D motion capture system (VICON) with 2 force plate has been used to measure angles and moments at the hip and knee joints for both the kicking leg and support leg. 28 healthy high level of Karate players volunteered to be part of this study. In addition, two case studies of Taekwondo players who had injuries in different joints, case one had lower back pain and case two had a left knee injury, both with more than 6-months rehabilitation were carried out. The aim of this PhD study will be to establish joint loading at the hips and knees of kicking practices in both a basic fashion and a competition type fashion. [Continues.]</div

Mixed Martial Arts Training Equipment and Footwear Needs

97 page

Mixed Martial Arts Training Equipment and Footwear Needs

97 pagesMartial arts are deeply rooted in many cultures throughout the world. In ancient Greece and ancient Sumeria, boxing and wrestling competitions were common and wildly celebrated (The History of MMA, 2019). Martial arts spread throughout the world, branching into a wide variety of grappling and striking styles that garner competition between one another to find out which is the most effective. As a sport, martial arts can be aggressive and violent while simultaneously rooted in respect and the mutual pursuit of growth (Jeet Kune Do, 2020). Modern mixed martial arts (MMA) continue to pursue that growth alongside the following question- What is the most effective blend of these arts to submit or subdue an opponent? The search for the answer to this question pits competitors against one another in one of the most dangerous sports in the world-Competitive MMA (Health Fitness Revolution, 2020). Competitive MMA demands relentless training to insure the highest level of skills and conditioning possible (Fitnescity, 2020). The training itself requires a certain level of risk, and the equipment used to train needs be as finely tuned as the athletes who use it. This paper will investigate how MMA athletes train by explaining the history of the sport, athlete needs, the current product environment, and the potential for innovative improvement in this product area. This research will lay the foundation for the design and creation of innovative training equipment and footwear that will improve safety in MMA training. The purpose of this design innovation is to look to the future of equipment and footwear for the elite male MMA athlete to optimize training and reduce injuries. This will be the first project to apply additive and generative design techniques to customize fit and function in MMA equipment, and focus on footwear that adapts to the needs of the elite MMA athlete. The physical ability of the elite MMA athlete is improving faster than the equipment that they use, in order to protect them properly their equipment needs to catch up and improve at the same rate

Representative testing of personal protection equipment

The purpose of the work reported within this thesis was to design and implement a series of tests which better replicate the impact conditions experienced during a game, and allow for quantitative measurements of performance of various items of personal protection equipment (PPE). The sports of cricket and taekwondo were used as case studies. The aim was to improve on existing testing protocols making them more representative of real life, an approach that has not been previously attempted in the literature and so required design of multiple items of novel equipment. A representative cricket impact test was developed utilizing a ball canon firing a cricket ball mass at an equivalent bowling velocity of 31 m/s (70 mph) and a novel, freely suspended force acquisition system with embedded accelerometers from which the transmitted force values could be derived. Throughout the testing secondary variables of coefficient of restitution (COR), deformation and contact time were measured from high speed video footage to give further insight into the impact mechanics of the three tested leg guards. Contact times were in the range of 3 ms - 4 ms, COR between 0.38 - 0.50 and deformation between 45 mm - 52 mm. These results were compared against other benchmark tests to establish how close the representative test was to an actual human related ball-pad impact and to estimate human tolerance levels to impact. A rig to mimic a human on human kicking impact in taekwondo was designed to measure performance of the piece of body protection equipment used in training and competition, commonly referred to as a hogu. Primarily a mechanical simulator was designed to replicate the speed and mass of a human leg impacting during a roundhouse kick. A force acquisition system was manufactured, capable of integrating with the kicking robot functioning, with a human torso sized and shaped anvil, using a similar accelerometer based system of force measurement as that introduced in the cricket testing. This test was then used to measure performance levels of nine off-the-shelf hogus and protective training pads. Using transmitted peak force and time to peak force (TTPF) as indicators of protection, these values were found to range from between 0.5 kN 7.5 kN and 9 ms - 23 ms across the pads indicating a major difference in the protection provided

White matter abnormalities in active elite adult rugby players

The recognition, diagnosis and management of mild traumatic brain injuries is difficult and confusing. It is unclear how the severity and number of injuries sustained relate to brain injuries such as diffuse axonal injury, diffuse vascular injury and progressive neurodegeneration. Advances in neuroimaging techniques enable the investigation of neuropathologies associated with acute and long-term effects of injury. Head injuries are the most commonly reported injury seen during professional rugby. There is increased vigilance for the immediate effects of these injuries in matches, but there has been surprisingly little research investigating the longer-term effects of rugby participation. Here we present a longitudinal observational study investigating the relationship of exposure to rugby participation and sub-acute head injuries in professional adult male and female rugby union and league players using advanced MRI. Diffusion tensor imaging and susceptibility weighted imaging was used to assess white matter structure and evidence of axonal and diffuse vascular injury. We also studied changes in brain structure over time using Jacobian Determinant statistics extracted from serial volumetric imaging. We tested 41 male and 3 female adult elite rugby players, of whom 21 attended study visits after a head injury, alongside 32 non-sporting controls, 15 non-collision-sport athletic controls and 16 longitudinally assessed controls. 18 rugby players participated in the longitudinal arm of the study, with a second visit at least 6 months after their first scan. Neuroimaging evidence of either axonal injury or diffuse vascular injury was present in 23% (10/44) of players. In the non-acutely injured group of rugby players, abnormalities of fractional anisotropy and other diffusion measures were seen. In contrast, non-collision-sport athletic controls were not classified as showing abnormalities. A group level contrast also showed evidence of sub-acute injury using diffusion tensor imaging in rugby players. Examination of longitudinal imaging revealed unexpected reductions in white matter volume in the elite rugby players studied. These changes were not related to self-reported head injury history or neuropsychological test scores and might indicate excess neurodegeneration in white matter tracts affected by injury. Taken together, our findings suggest an association of participation in elite adult rugby with changes in brain structure. Further well-designed large scale studies are needed to understand the impact of both repeated sports related head impacts and head injuries on brain structure, and to clarify whether the abnormalities we have observed are related to an increased risk of neurodegenerative disease and impaired neurocognitive function following elite rugby participation

White matter abnormalities in active elite adult rugby players

The recognition, diagnosis and management of mild traumatic brain injuries are difficult and confusing. It is unclear how the severity and number of injuries sustained relate to brain injuries, such as diffuse axonal injury, diffuse vascular injury and progressive neurodegeneration. Advances in neuroimaging techniques enable the investigation of neuropathologies associated with acute and long-term effects of injury. Head injuries are the most commonly reported injury seen during professional rugby. There is increased vigilance for the immediate effects of these injuries in matches, but there has been surprisingly little research investigating the longer-term effects of rugby participation. Here, we present a longitudinal observational study investigating the relationship of exposure to rugby participation and sub-acute head injuries in professional adult male and female rugby union and league players using advanced MRI. Diffusion tensor imaging and susceptibility weighted imaging was used to assess white matter structure and evidence of axonal and diffuse vascular injury. We also studied changes in brain structure over time using Jacobian Determinant statistics extracted from serial volumetric imaging. We tested 41 male and 3 female adult elite rugby players, of whom 21 attended study visits after a head injury, alongside 32 non-sporting controls, 15 non-collision-sport athletic controls and 16 longitudinally assessed controls. Eighteen rugby players participated in the longitudinal arm of the study, with a second visit at least 6 months after their first scan. Neuroimaging evidence of either axonal injury or diffuse vascular injury was present in 23% (10/44) of players. In the non-acutely injured group of rugby players, abnormalities of fractional anisotropy and other diffusion measures were seen. In contrast, non-collision-sport athletic controls were not classified as showing abnormalities. A group level contrast also showed evidence of sub-acute injury using diffusion tensor imaging in rugby players. Examination of longitudinal imaging revealed unexpected reductions in white matter volume in the elite rugby players studied. These changes were not related to self-reported head injury history or neuropsychological test scores and might indicate excess neurodegeneration in white matter tracts affected by injury. Taken together, our findings suggest an association of participation in elite adult rugby with changes in brain structure. Further well-designed large-scale studies are needed to understand the impact of both repeated sports-related head impacts and head injuries on brain structure, and to clarify whether the abnormalities we have observed are related to an increased risk of neurodegenerative disease and impaired neurocognitive function following elite rugby participation