A student found a strong correlation between the age of people who run marathons and their marathon time. Can the student say that young people will run marathons faster than older people? Explain.
Elite marathon race times improved from 5 to ~20 years, remained linear between ~20 and ~35 years, and started to increase at the age of ~35 years in a curvilinear manner with increasing age in both women and men. The sex difference in elite marathon race time increased non-linearly and was lowest at the age of ~49 years.
