Law of nature is same for all
Even though holy men have developed greater immunity against diseases, when the strength of the cause for diseases exceeds the strength of immunity developed, they also have to suffer from those diseases, it would be clear that the justice of nature never fails.
Weather one is a holy person or an ordinary individual he has to accept the due award or punishment under the law of nature. With this explanation in mind, please study the biographies of saints and holy men and you would see for yourself that the theory is valid.
Yogiraj Vethathiri maharishi,
Founder of simplified kundalini yoga and world community service centre
My father who was direct disciple of Vethathiri trained us how to jump in to the water (water here referred as meditation and stages of yoga to Samadhi) but Yogi Raj Vethathiri Maharishi taught us how to swim in the water, and great master His holiness swami Sivanandhar taught us how to walk in the water with the human body.