As girls get older and exams loom, girls and parents talk to me about restricting time spent on sport in order to free up time for academic studies. I really encourage them not to for two reasons.
Firstly there is lots of research that has shown that playing regular sports actually helps boost your brain and improves cognitive function in a myriad of different ways. It also helps reduce stress which contributes to better performance. So time spent playing sport is time spent improving your brain.
Secondly it is rare that the time spent playing sport is then spent studying. When I was at University I played sport on Monday nights, Wednesday afternoons and Saturday mornings. My flat mates had all that time to study but they didn’t do any more work, have more friends or get a better degree. They just filled that time with different activities. They slept in every Saturday morning for instance and were still in their pyjamas when I got back from home matches. In short, there is a limit to the number of hours you can effectively study each week and that still leaves plenty of time for sport.
So giving up sport won’t make you do better in exams but playing regular sport will help you get better academic results.