Happens during any significant "physical activity" and it can be a real pain when they slip or fall off during a roll that you have to stop everything lest they get mangled. The trade off is that you cant see and enjoy the view as well. There are sprays you can apply that temporarily repel fogging, and coatings you can have put on when they are made (but not always compatible with others.)
Happens during any significant "physical activity" and it can be a real pain when they slip or fall