nobody misses during winter. It is mandatory. In the summer you are expected to be there if you are in town for the summer. If you aren't in town, you are sent with a program you are expected to do on your own. When you get back you get treated as if you did it, and the coaches can tell if you didn't. If that happens, they have a way of making you feel like it would have been easier to just do the work in the first place.

Having said that, a coach can clear you to be gone (like to go to Hawaii with your family), but you will be expected to show up in the same shape you left, with consequences if you don't.

I missed a weight room workout once because I had a leg and a shoulder injury and figured I couldn't do anything. I should have cleared it with the trainers first, but I didn't because I figured the coaches knew. Big mistake. You don't get away with much.