Sports or no sports?

So I’m a rising senior and I have done track and cross country throughout the past 3 years, and have been on Varsity on the past 2. Now that the season is going to start in a few weeks, my parents are trying to ban me from doing sports during my senior year because they supposively don’t want me to miss too much school. But honestly, they think that I can’t balance my schoolwork and sports, even though I have been in honors and AP classes for all of high school and have a high GPA. They also said that I’m easily replaceable for the team since I’m “just another runner” and that I should only run if I want to run competitively in college and that I suck, even though I was an alternate for the state cross country meet, and at the top of my team.
I need help figuring out how to convince them otherwise because I’m not that good at putting my emotions into words.

Sorry that your parents don’t understand your feelings. I have some friends in similar situations. I think you just need to tell them that 12th grade is easier than 11th in terms of academics and since you did well throughout high school, there’s no way that your grades will drop. I think basically what you wrote in your post you should say to your parents. Say that you’re not “replaceable” because you are one of the best runners on the team. Good luck. I hope they understand.