As an adjective, the word “ancient” is fairly elastic. “Ancient American” falls somewhere in the mid 1600’s. “Ancient Chinese” dates back many centuries earlier than that.
“Modern,” is similarly juxtaposed. Consider this statement, “Modern Tai Chi began in the mid-1500’s.” The most modern form, or style, is Wu Tai Chi which emerged in the mid 1800’s.
Tai chi is a gentle exercise program that is a part of Traditional Chinese Medicine (TCM).