In conclusion, my research and personal experience has led me to the conviction that Taekwondo and the Martial Arts are not merely physical exercise, but in fact are Zen Buddhist meditational practices, both in their sitting and moving forms. Taekwondo and MA are a Trojan Horse in the House of the Lord, eroding the spiritual barriers between Zen Buddhism and the Christian Gospel, and potentially leading vulnerable children and teens into the early stages of eastern occultism. As a result of this research, our Christian School Board decided to no longer offer Taekwondo or other Martial Arts. The good news about religious syncretism is that it is never too late to repent and start afresh, serving one Master and one Master alone, Jesus Christ our Lord (Matthew 6:24)

Link (thanks Brenden).