The hidden forces behind winter sports
Photos by Kathy F. Atkinson and iStock and courtesy of Alfredo S谩nchez | Photo collage by Jaynell Keely February 12, 2026
91原创 professor explains how Olympic athletes optimize physics to reach peak performance
Long before he earned the nickname the 鈥淨uad God,鈥 U.S. men鈥檚 figure skating champion and gold medalist Ilia Malinin was part of a 91原创 biomechanics study that measured jumping ability and motion, part of a broader effort to understand how forces, speed and body mechanics impact an athlete鈥檚 performance.
Now when Malinin launches himself into the air to do a quadruple axel 鈥 four and a half rotations 鈥 he鈥檚 not only making history as the only skater in the world to consistently land the jump, he鈥檚 putting his knowledge of that science to work.
All of the sports at the Winter Olympics in Milano Cortino involve some physics in action. For figure skating, ski jumping and curling, two of the basic laws of the physics of motion are at play: Gravity governs motion, and friction resists it.
91原创aily spoke with Alfredo S谩nchez, assistant professor in the Department of Physics and Astronomy in the College of Arts and Sciences, about the science behind the three sports, and how athletes test those laws of motion and the limits of their bodies to create a peak performance.
Figure skating: the challenge of rotational inertia
Figure skating jumps require a balance of strength, timing and body control. Athletes have to generate enough force and speed to lift off the ice high enough and spin fast enough to complete all of the revolutions before gravity pulls them back to the ice. Throughout the rotations they are fighting resistance to the spin, called rotational inertia.聽
But there鈥檚 a trick to combatting inertia.
鈥淲hen skaters pull their arms close to their bodies, they reduce their rotational inertia, that resistance to rotation,鈥 S谩nchez explained. 鈥淭hat allows them to spin faster without having to propel themselves.鈥澛犅
Each additional rotation requires more jump height, more speed and more precise control. For the quad axel, Malinin has optimized both his strength and how his body mass is distributed while rotating.聽
Does that mean a quintuple axel is on the horizon?聽
鈥淚 would never say never, but at some point we run into the limits of the human body,鈥 S谩nchez said. 鈥淭here are limits as to how much energy can be burned in a short time interval, how far the muscles can stretch, how far the joints can rotate. The question is where are those limits?鈥
Ski jumping: fighting gravity and air resistance
While skaters manage resistance to rotations, the biggest challenge for ski jumpers is managing air resistance, or drag, in a straight line. Once a jumper leaves the starting point at the top of the ramp, gravity immediately takes over, pulling them down. Controlling how air flows over and around the athlete while they descend determines how far they go.
鈥淎t those speeds, air resistance becomes the dominant factor,鈥 S谩nchez said. 鈥淩esistance increases dramatically the higher the speed, so one of the goals is to have a position that causes air resistance to be minimized.鈥
To do that, jumpers get as close as possible to their skis, using a tuck position while on the ramp and leaning over while in the air, shaping themselves so air moves smoothly around them. Athletes adapt their style to their individual body shape and size to achieve the best 鈥渁erodynamics of the technique,鈥 according to S谩nchez.
While the familiar V-shape may seem to contradict the idea of reducing resistance because the front of the skier鈥檚 body seems more exposed to the air, it has resulted in longer jumps. S谩nchez said the form allows the athletes鈥 bodies to have more of a curved shape overall as they fly, making the air flow in streams around it and providing an upward lift force.聽
Curling: steering with friction and spin
Curling may look easy, but it may be the most strategically complex winter sport from a physics standpoint, according to S谩nchez. It is the only winter sport that allows athletes to actively alter an object鈥檚 path after it has been released, requiring the athletes to understand the forces that contribute to the trajectory of the granite stone, and how the sweepers can change that trajectory.聽聽
The stone鈥檚 curved motion, or curl, is determined by how much it is spinning and how much friction there is with the ice. When it is spinning, friction acts unevenly across the stone鈥檚 surface, causing its path to bend.聽
By brushing the ice, sweepers slightly warm and smooth the surface, reducing friction. This can help the stone travel farther or curl less sharply, allowing teams to fine-tune shots in real time.聽
The key to success lies in consistency. Teams must know exactly how much spin, force and sweeping will produce the exact trajectory they want for any situation.
鈥淭he question for the athletes is, how they can, with practice, make sure they consistently give the stone the force and the spin they want,鈥 S谩nchez said. 鈥淵ou plan based on that. Some people could be better at throwing to consistently hit the other stones, or consistently giving spins. Or you might want to plan for something more defensive. It鈥檚 all about what you want to accomplish.
鈥淚t's interesting how friction, this fundamental phenomenon which we experience every day, can lead to this interesting sport with its own strategy and tactics,鈥 he said.聽
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