Kyo

Sparring is a sport - a mental as well as physical exercise. In no way does it prepare you for the real thing. But I suppose that isn't the point of this thread.

I'm not sure exactly what your definition of full-contact sparring is, especially in Aikido. In various other hand-to-hand martial arts, there is sparring with varying degrees of armor, from only cup and foam helmet to a full suit of chest protector, shin/forearm pads, etc. I would recommend in any free-sparring situation that you have at least a helmet and groin protector. Few people hit hard enough with sufficient accuracy to break a rib or dislocate a shoulder - and those that can are usually good enough to know when to pull their punches. Hits to the head and groin, however, are commonplace, and it doesn't take very much to cause serious injury to the head. A poorly-placed (or well-placed, depending on your view of things) elbow or knee could easily mean a trip to the hospital - preventable by just wearing a dorky-looking helmet.

In two of the three hand-to-hand martial arts I'm studying, we are told not to pull our punches and kicks, and we spar for points - a point doesn't count if your opponent's body doesn't move violently after you hit them. Tapping them with a fist doesn't cut it, nor does a weak fade-away kick. Blows to the head, below the belt, and to the back are almost always forbidden though, because the chance for serious (ie. permanent) injury is too great.

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