The typical hit in fencing noticable, but doesn't hurt. The occasional hit will sting for a bit and may leave a small red mark for a day or two. Fencing is one of the safest sports there is. An Ontario Government study found that of all sports surveyed it was second only to lawn bowling in it's safety record. In recent years the introduction of better equipment has made it even safer.
Most injuries are of the nature of twisted ankles or pulled ligaments.
It is possible for a broken blade to penetrate the protective clothing, but this is extremely rare. Learning to Fence Fencing is an enjoyable sport or pastime for people of all ages. The only prerequisite is enough dedication to stick with it for a while. The learning curve for fencing is generally quite long. In few other sports do you have to learn to walk all over again and learn to make finger movements as fine as are used in writing while holding a half kilogram mass in your hand.