Doing Martial Arts With KC?

[Louise Pembroke]

can't say I would any sport which would risk a blow to my face, sharp contact with someone else or sharp head movements

[James Colclough]

I agree that's why I never refer to it as a sport or teach anyone under 18

[Matthew_]

That would depend on the style!
Kung-fu is clearly a martial art rather than a sport but once you begin to compete rather than teach the style it can become a sport.
For example, Ju-Jitsu is predominantly not a sport and I would not refer to it in that way. Judo is defintely a sport however because it centres on competition. To protect the players, it is heavily regulated and you are in theory less likely to be injured.
Ironically, I have been more badly injured in Judo than when I did Ju-Jitsu. Got plenty of bruises in Ju-Jitsu but that was it. I managed to dislocate my shoulder playing Judo. However, its a very minor injury and nothing worse than you could get playing football.
From a KC point of view a good instructor should be able to adapt the lessons for sufferers of just about any condition. Its a question of motivation. The purpose of our club was to teach self-defence and this has to be applicable to anyone. One Ju-Jitsu throw (Hanai-goshi) was developed by a man with one leg as an adaptation to his disability. The whole point of martial arts is to develop techniques of overpowering a potentially more capable opponent.