Muscular or tension headaches are the most common.
The head itself is wrapped in muscles. They aide turning the head, moving the jaw, your eyes and facial movements.
These headaches are triggered by stress and long sedentary periods, like working or flying.
They can also be brought on by postural changes. This can be as a result of being sedentary, or from exercise (like cycling).
Teeth grinding, TMJ issues and tension in the eyes can also bring on headaches.