The document discusses 5 mysterious reasons why exercise is important: 1) It protects memory and thinking skills as we age, 2) It speeds up recovery from injury or surgery, 3) It has positive effects on menopausal symptoms in women, 4) It prevents mental health problems, and 5) It increases self-esteem. The author encourages the reader to dig deep and identify their personal reasons for wanting to lose weight or maintain a healthy weight through exercise to ensure long-term success and commitment.