The secret of good health all depends on one's "first cell", that is, if it is healthy so will be the rest of the body be. In fact, when the first cell is strong, one has a good stamina in all things related to the body. I found this out from two separate newspaper article: one from an article on Chinese Art of Qigong and secondly, from an article on Silat, the traditional Malay Art of Defense. Our first cell is situated in an area behind the navel but the muscle there is the weakness in the body because it is not attached to any body. The only way to compensate for this shortcoming is to build up that muscle through sit-ups. I unfortunately had 2 hernia operations and the surgeon said because of my senior age, I should not over do sit-ups for fear the medical mesh might tear and that would require another operation more difficult than the former. This is why I limit my sit-ups to 30 times. Alhamdulillah, ever since I followed this principle, I have not suffered any fever nor fallen sick.