Qi Gong Health Benefits

Had a long discussion with a Qi Gong (Chi Gong) master. His claims of health benefits seem to stretch credibility - longer life, hair turned from grey to black, knee problem disappeared, general feelings of confidence and well being. He described the practice in almost religious terms. On the other hand, I should hope to look so good when I’m 67. There wasn’t an ounce of fat on him, good muscle tone and could pass for a man in his forties (with different clothes).

Studying with him would cost more than I can afford, but I’m still interested in the practice. Any expats with experience studying Qi Gong in Taiwan?