Honestly, if you feel as though you could be comfortable with contact lenses in, it is much better idea. If you have to use any kind of physical force against somebody, you run the risk of breaking your glasses and possibly injuring yourself if the broken glass harms you. If you have broken your glasses, you are then at a disadvantage because you may not be able to see everything that you need to, and might no longer be able to drive. So ultimately, it is certain that having contact lenses is a better idea, and would suit the job much more.