THE CLAPPER 2018-2019 | Page 47

Dr. Samir Aouadi, Editor of Surface and Coatings Technology and Professor of Materials Science and Engineering at the University of North Texas, has over 15 years of experience in using various techniques to modify materials’ surfaces. He explained: “Coatings are currently used to extend the lifetime and enhance the performance of several components that are used by athletes. For example, coatings are used to reduce friction improve on the wear resistance of bearings used in high performance bicycle bearings. In addition, protective ceramic coatings are also used for golf club heads, air rifle barrels, and in various bow modules used in archery to provide surface lubrication as well as impact, scratch, and corrosion/chemical protection. Finally, epoxy coatings are used on kayaks and on paddles to enhance their scratch and corrosion protection.” Hugh Trenchard, an independent researcher in Victoria, British Columbia, Canada, whose interest in peloton dynamics and collective behavior stems from his experiences as a competitive cyclist, runner and duathlete. His primary research objective is to show how self-organized principles of peloton dynamics are ubiquitous across biological collectives and represent fundamental principles of evolution. He explained: When cyclists save energy by drafting, they also couple their energy expenditures. This means that each cyclist’s output is directly affected by the outputs of their nearest neighbors. This interactivity produces self-organized collective behavior. ‘Self-organized’ means that behavior emerges bottom-up from basic physical principles; i.e. the collective behavior is not driven by top-down demands, such as when a leader shouts at team-mates to move to certain positions. Of course top-down behavior does occur in pelotons, and cyclists constantly adjust positions according to team tactics and strategies. However, certain collective behaviors can be shown to emerge from underlying physical coupling principles. The study of collective behavior is an area of physics known as complexity theory, and includes the study of flocks, schools, and herds. “Coupling among cyclists is a function of three basic physical/physiological factors: the speed or power- output of a leading cyclist, the energy saved by drafting, and the maximal sustainable outputs of the drafting rider. With these three factors, we can model the collective behavior of pelotons. We can show that there are different thresholds and phases of collective behavior. A phase transition means there is both a quantitative and qualitative difference in the pattern formation and structure of the peloton. Such phases include cyclists forming a single-file line, when they are cycling near their sustainable maximums and cannot easily pass others; and a dense and compact formation, when riders cycle at lower outputs and can pass their neighbors.” “Thus, drafting is used to reduce wind resistance and it is seen in cycling, running, swimming, and car racing as well. Drafting and physiological factors produce collective behavior and phase transitions. Computational Fluid Dynamics is a computational technique used to model drafting that can help athletes to prepare and train more efficiently.” Read more at: https://www.elsevier.com/connect/ the-physics-of-sports THE CLAPPER 2018 - 2019 47 reducing the moment of inertia and her friction with the air. Since angular momentum is conserved, her rotational velocity must increase to compensate. Aerodynamics in sports equipment, football and cycling Aerodynamics is a term of physics that describes the ability of an object to overcome air resistance. Thus, it can be applied to cycling, the bicycle composition and design, the clothing worn by the cyclist, and even the positioning of the rider on the bicycle.