Author: Kayla Otoo
Editors: Jaylen Peng, Winnie Mok
Artist: Emily Tai
This year marked the 30th anniversary of the Summer Olympic Games. Millions of accomplished athletes gathered together in Paris, France, to celebrate their talents. Among them was Sha’Carrai Richardson, the current world record holder in women's 100m, at a baffling 10.71 seconds. In the final 4x100m relay race, Sha'Carri lagged behind her opponents due to her late start. Nevertheless, she bounced back, quickly breezing through and securing the Gold for Team USA. Upon further inspection, it is truly fascinating how a 5’2 woman could get past many who towered over her. How is this possible? People often believe taller athletes can sprint faster as they have longer strides. For Instance, Usain Bolt stands at a whopping 6 '5 and is the fastest man ever to run 100m at a striking 9.58 seconds. But Sha’Carrai Richardson’s performance proves height is not a defining factor of speed. Speed is simply just a matter of physics—specifically, biomechanics.
A runner's movement can be described in waveforms. With each step, a runner moves in vertical oscillations. To illustrate this, a waveform is ignited as soon as a runner strikes their foot on the ground. The wave climbs slowly when the runner exerts more force towards the ground, reaching its peak at max acceleration. As soon as they lift their leg again, the wave slopes down; thus the whole process is repeated. Understanding this motion, however, is not what determines how fast someone can run— the force determines speed. One of the major forces involved in sprinting is propulsion. Propulsion results in a vector quantity that can be represented with both x and y vectors. The X direction of the vector allows a runner to propel forward due to Newton’s 2nd Law, which states the acceleration of an object is dependent on the mass of an object and the amount of force applied, whereas the Y direction allows a runner to overcome gravity and move upwards due to Newton’s 3rd Law of motion: for every action there is an equal and opposite reaction.
Without force, a sprinter would fail to accelerate, which proves that stride length is not everything. Even though force is at the center of biomechanics, many other types of force other than propulsion affect a person’s speed; for instance, resistive forces. These forces include gravity, friction, and air resistance, and if not overcome, they can significantly affect a sprinter’s speed, thus slowing them down. Gravity governs many things, such as how hard a foot strikes the ground, affecting how much force is felt in the muscles, ligaments, and tendons. Friction allows your body to extend fully and keeps a person's movement relative to the ground. Similarly, air resistance reduces the velocity of a runner's ability to move forward. But when an athlete overcomes these forces and uses them to their advantage, that is when they can reach their fastest speed. At Southern Methodist University’s Locomotor Performance Laboratory, three elite runners were invited to run on the World’s Fastest treadmill. In the end, Peter Weyand, director of the lab and world-renowned sprinting expert, concluded, “There is a single factor that determines a runner's speed…how much force they deliver into the ground relative to their weight.”
This proves that speed is just a matter of force and strength. Apart from physics, many factors can impact a runner's speed, such as posture, diet, cadence, V02 Max (oxygen intake), and even genetics, which have proven sometimes to have a significant impact since they play a role in the amount of ACTN3 and ACE genes a person can have. This correlates with the formation/distribution of fast twitch muscle fibers, which allow a person to speed. Moreover, studies have shown that many elite sprinters carry the gene ACTN3, which produces the protein alpha-actinin-3 found in fast twitch muscles. On the other hand, the ACE gene is renowned for increasing endurance performances as it provides instructions for creating angiotensin (protein-converting enzyme). However, force is the ultimate determinant of speed. So, it can be concluded that a runner's height does not have a significant impact on whether or not they will be fast or slow. By raising awareness of elite athletes, teachers, and coaches and understanding the biomechanics behind sports, not just in the world of Track and Field, athletes can perform at their very best. It will not only help their development, but it will also help reduce injuries allowing athletes to stay in top condition. On top of that, biomechanics will not just be advantageous to athletes. Moreover, understanding it can improve people’s daily activities, such as walking, sitting, and lifting. Even yours!
Citations:
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Accessed 21 Aug. 2024.
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