I am that mom that will sometimes force an activity on her children for the greater good. I am that mom who will tell you to go play outside in the heat because you will not die. I'm certain you won't because I didn't, and you've got unlimited water and shade.
You'll be fine.
Olivia is a lot better about it than Jackson is. Jackson is, hands down, the laziest kid I have ever met. He hates all activity. He doesn't enjoy sports. He tries sports, and then when he realizes he's not star quality he decides it's dumb and he'd rather sit on the couch. To get him to do anything you have to just force him. If you give this child a choice, he will always take the easiest route.
So every summer a local company that runs a major marathon has these smaller "just for fun" kids running races. Every year we somehow miss the one at our local park but come hell or high water, we make it to the final picnic because there is a free dinner involved and I'm all about free food when it's hot out because I'm not trying to cook.