This document discusses how beliefs can be self-fulfilling prophecies that impact our health, fitness goals, and aging process. It provides examples of how the belief "I can't get fit" leads to lack of exercise, weight gain, and proving the negative belief true. In contrast, the belief "I believe I can get fit easily" leads to motivation, exercise adherence, weight loss and achieving fitness goals by proving the positive belief. The document also discusses how inherited expectations and negative influences from others can impact how long our bodies last, with some estimates being 115-130 years without those factors.