Effect of wear and outsole material on the frictional performance of basketball shoes across playing surfaces

In basketball, slip-related injuries pose a significant risk, often caused by reduced friction between the court surfaces and shoes due to outsole wear. While numerous studies have investigated the grip characteristics of basketball shoes on various surfaces and under different conditions, the impact of outsole wear on friction has not been thoroughly examined. This study evaluates the frictional performance of 14 basketball shoe outsoles under progressively worn conditions using a belt sander across three common playing surfaces: polyurethane, synthetic, and wood. The available coefficient of friction (ACOF) was measured under both dry and wet conditions using a portable slip-testing device. Results indicate a progressive decline in ACOF with increasing outsole wear, regardless of the surface or environmental condition. A higher ACOF was observed in outsoles with herringbone treads, especially in wet conditions. Shoes with deeper treads and wider grooves exhibited consistent friction across all testing scenarios. Additionally, the outsoles demonstrated uniform friction on wooden surfaces in dry conditions. These results are expected to provide valuable insights into basketball shoe design and selection, and to help establish suitable replacements that optimize performance and safety.