Conclusion
In conclusion, our findings provide evidence supporting the reciprocal relation between intrinsic motivation and individual deliberate practice in specializing team sport athletes. Our findings also indicate that athlete's intrinsic motivation was stable and that participants with higher initial intrinsic motivation score had more of an increase in intrinsic motivation over the 1-year period. We argue that parallel process LGM, as used in the present study, represents an important step for practice history research toward examining the dynamical developmental process of specializing team sport athletes over time.