Grit subcomponents are differentially associated with practice trajectories underlying expertise development.

Practice is essential for skill acquisition, yet the psychological traits driving changes that occur with practice remain unclear. We extend previous work that identified grit as a key psychological trait underpinning practice accumulation in football. More specifically, we examined whether similar patterns exist in alpine ski racing, a sport characterized by seasonal constraints and limited practice opportunities. We collected retrospective estimates of practice hours from N = 231 elite youth skiers in Austria and the USA aged 6 to 19 years, alongside current measures of grit's subcomponents, Consistency of Interests (CI) and Perseverance of Effort (PE). We used Generalized Additive Models (GAM) to analyze nonlinear practice trajectories. CI was positively associated with practice accumulation during early developmental stages up to age 12 years. From age 12 onward, PE became the dominant factor associated with practice. Notably, grit had the most pronounced association on engagement in unstructured practice activities, such as self-training and free play. These findings suggest that grit might impact expertise indirectly by affecting how athletes engage in practice over time. Understanding the differentiated roles of CI and PE in practice accumulation offers valuable insights for talent development programs; we emphasize the importance of fostering psychological traits that support sustained commitment and resilience in athletes.