The Physics of Gymnastics

The Physics of Gymnastics


McKenna Kelley! Perfection for McKenna Kelley! Physics plays a significant role in all the gymnastic events, including the floor competition, and just recently, LSU women’s gymnastics star, McKenna Kelley, scored a perfect 10 on her floor exercise. Let’s take a look at the physics behind the floor competition and the tremendous forces her body must endure as she executes her routine. Let it roar tiger fans for McKenna Kelley! So while the gymnastics floor may look like an ordinary floor, it’s actually composed of many layers, including carpet-bonded foam, a fiberglass reinforced plywood and then, of course, the main feature of the floor are the power springs. So overall, over the entire area of the floor, this makes the floor resemble a giant trampoline, which then helps the gymnast to jump higher and further. So on her first pass, which is the double layout, notice she builds up her kinetic energy by sprinting, and then plants, and then springs off the floor. She explodes upwards, greatly increasing her gravitational potential energy. But in this pass, she has a tremendous amount still of translational kinetic energy, so by the time she lands, she actually takes a small step backwards. So Newton’s First Law, a body in motion wants to continue in motion in a straight line, and so it actually carries her slightly past her landing point. So on her third pass, again, she greatly increases her kinetic energy with her approach and then springs forward. Now she gets crazy height, so a lot of gravitational potential energy, and she forms into a tuck position. By bringing her legs in close to her axis of rotation, she lowers her moment of inertia, which increases her speed at which she rotates. So upon landing, all of that translational and rotational kinetic energy has to be dissipated and the impact forces can be many times McKenna’s weight. It’s a testament to all of her hard practice and training and conditioning that allows her to execute these tumbling passes perfectly. ♪♪

Leave a Reply

Your email address will not be published. Required fields are marked *