The scientific secret behind squeaky sneakers will ensure you will never hear the noise of a basketball game the same way again.
Scientists have researched the unmistakable noise that happens when basketball shoes slide on a polished court by examining interactions between surfaces at speeds.
In their study, applied mechanics researcher professor Katia Bertoldi and colleagues filmed a basketball shoe squeaking as it strikes a smooth glass plate, and used high-speed imaging to capture deformations of the rubber sole pulsing in bursts across the surface.
The study found that the pitch of the squeak matched the rate of the bursts—which is determined by the stiffness and thickness of the shoe sole—and also discovered that if a soft surface is smooth, the pulses are irregular, and no sharp sounds are produced.
Soles with ridged surfaces—like the grip patterns seen on shoes worn by basketball players—produce consistent pulse frequencies. This is what gives a game of basketball its notable squeaking sound.
“Our high-speed imaging and sound measurements reveal a previously unseen mechanism behind squeaking at soft–rigid contacts. We observe rapid ‘opening slip pulses’—similar to earthquake ruptures—that travel along the interface and carry the slipping motion, moving at roughly the shear-wave speed of the soft material, “Bertoldi told Newsweek.
“When we add thin ridges to the rubber surface, the ridges guide and confine these pulses so they repeat regularly, producing a stable squeak at a clear, tone-like (musical) frequency. Without ridges, the pulses occur irregularly and the sound becomes broadband and noisy rather than musical.”
Previous studies concluded that pulses are created when two materials moving against each other stick and slip, but these studies had focused on slow movements, which do not create squeaks.
Commenting on the study in an accompanying News and Views, editorial author Bart Weber of the University of Amsterdam’s Institute of Physics noted: “As the sliding speed is increased above the critical sliding velocity, several pulses are launched during each oscillation, grouping into short bursts.
“By altering material properties and surface patterning, the authors even demonstrated that frictional sound can be shaped deliberately, briefly turning sliding rubber into a musical instrument.”
Weber also noted that “the work raises a deeper question about the nature of sliding at strongly pinned interfaces,” adding: “If these processes can eventually be understood and controlled, they might offer routes for deliberately tuning frictional behaviour.”
Researchers believe that understanding the dynamics that happen between two surfaces could shed light into the effects of friction across a range of systems, such as geological faults.
A geological fault is a fracture or zone of fractures between the plates of rock that make up the solid, outer part of the planet. It’s believed that earthquakes occur when pressure builds up at these faults, leading to sudden slips or breaks.
Bertoldi told Newsweek the next steps into exploring the study’s results will include examining “how richer, more intricate surface textures can reliably control friction and acoustic output under a wider range of loads and sliding speeds.
“At a deeper level, the solitary-like character of the slip pulses raises fresh questions about the fundamental dynamics of friction across scales.”
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Reference
Djellouli, A., Albertini, G., Wilt, J., Tournat, V., Weitz, D., Rubinstein, S., & Bertoldi, K. (2026). Squeaking at soft–rigid frictional interfaces. Nature. https://doi.org/10.1038/s41586-026-10132-3