Supplementary activities for Table Tennis

What would you recommend as good activities or exercises that will contribute to or compliment table tennis? What sports or activities have you found to be good cross training?

Hi John,

I have found Tennis useful.  I have also found things like Qi Gong or Tai Chi useful.

I didn't do any form of martial arts when I was playing however I have done some later and I think it would be useful for balance.  I also did Pilates which I think would be useful.

Certainly weight training in the correct form will help as well.