<human>: I am in a tough place currently and I was hoping to get some advice or good ideas from other parents. My son (11 years old) is finding excuses not to go to his workouts. Excuses that I cannot really check (headaches, bellyaches, "hurt my knee in school today" with no visible mark etc). 

He started a new sport this Autumn (chose it himself) and I see that he likes a part of it, but is afraid to do other parts (I've sat in the sidelines for some of his workouts) and is starting to understand that it is tough work in other parts. He tells me he doesn't like this sport any more and wants to drop out of it. However, he had similar excuses and meltdowns with previous sport as well - one he at peaceful moments confirmed that he likes, but decided to switch out from just for change this Spring. I don't think the excuses have anything to do with specific sports, just the fact that he has to get out of home, however I am thoroughly tired of dragging him there all the time, arguing about it with him, convincing "the headache will pass" when I really don't believe he has a serious headache etc.

Can you condense the text into a few key points?
<bot>: How do you get your kids to attend to their workouts? At what age do you think they should be able to decide about dropping out of a workout for themselves?