This section is from the book "The Hygienic System: Fasting And Sun Bathing", by Herbert M. Shelton. Also available from Amazon: The Hygienic System Vol III Fasting and Sun Bathing.
Benedict devotes consideration to strength tests during the fast. He says "The tests made by Luciani on Succi in which a dynamometer was used to measure the strength of the right and left hands, showed results seemingly at variance with popular impressions. Thus, on the 21st day of the fast Succi was able to register on the dynamometer a stronger grip than when the fast began. From the 20th to the 30th days of the fast, however, his strength decreased, being less at the end than at the beginning of the fast. In discussing these results, Luciani points out the fact that Succi believed that he gained in strength as the fast progressed, and hence probably did not exert the greatest power at the beginning of the experiment. Considering the question of the influence of inanition on the onset of fatigue, Luciani states that the fatigue curve obtained by Succi on the 29th fast day was similar to those obtained with an individual under normal conditions. . . ."
Levinson says: "Many people think that during a long fast you have to sit down on a Morris chair reading newspapers or dozing because you have not sufficient strength for doing any work at all. If you weigh two hundred pounds and your normal weight should be one hundred and thirty-two you can fast for sixty days and for each day you increase your strength, because you are coming back to your normal point. I started this fast from my normal weight; I have gone through thirty-two days of continuous scientific hardships and tortures, but I never felt that I was losing any strength and there are the dynamometer tests to show it.
"On the last day I could press up to one hundred and twenty pounds without any difficulty with my left hand and I never do any regular exercise except walking. I could go up and down a steep flight of steps to my balcony without support or shaking in the knees. I never lay down except during experiments.
"I used to pass the few spare hours that were at my disposal writing long letters and busying myself actively; on the evening of the last day I was dancing in the laboratory and laughing. In the afternoon the elite of the medical and scientific men of Harvard University and the medical colleges came to see me. I stood up for nearly two hours and for the whole time."
Telling of his discussion with the reporters at the end of his experimental fast he says: "I explained to them the impressions of my fast, compared them with those of my precedent fasts and answered many questions with my spirits up and without feeling the least exhaustion. Those that feel any lack of strength during a fast are to be classed in the same category with those who feel hungry. They are nervous, and very impressionable people, and their sufferings are only the baneful effect of their too vivid imagination.
"If you suggest to yourself that you are strong and that you can walk two miles on the thirtieth day of your fast, believe me, you can do it without great difficulty, but if you fix in your weak mind that you are going to faint and worry and persist to worry about it, be sure that not a very long time will elapse before you faint really, a victim of your wrong auto-suggestion."
What may, at first, seem paradoxical is the fact that when a patient becomes very weak in fasting, if he persists in the fast, the weakness ceases and he grows stronger. Indeed I have seen patients who were one day so weak they could hardly raise their heads from the pillow and, next day, still fasting, were so strong they wanted to get out and do things. Great weakness, bordering on prostration may be seen in certain crises, especially in vomiting, so long as the crisis lasts. As soon as the crisis has ended, strength returns with a rush.