I honestly don't see any foul connection of chi and martial arts in regard to Christianity. I meditated and was involved with martial arts for a while, and meditation basically clears the mind and allows focus of your thoughts and actions. Only if someone was doing evil with their fighting skills, or meditating in foul ways (this is possible, but not encouraged by any self-respecting dojo I've heard of personally).
however, I must say that on two occasions back in my 20's that I was quite intoxicated and meditated with heavy music, and I felt and saw in my mind, evil presence. It was scary and that was the end of that. My counselor at the time (new age) said "yes, this can happen". So obviously I don't encourage such behavior at all, that's what new age stuff opens you up to.
So I would encourage anyone doing this to stay in meditating on the quiet, inner calm self, for personal goodness. It is very effective to use in tournaments. And I do believe it can aid in connecting with the Lord in a good way. I think it's all about "where you are" in Christ.