Dr. Jones discusses the role of exercise in weight loss and weight maintenance. He explains that in the short term, exercise is not necessary for weight loss, as it can be achieved through diet alone. However, for long-term weight maintenance, exercise, specifically resistance training, is crucial. Dr. Jones emphasizes the importance of building muscle mass, as it increases metabolism and insulin sensitivity, leading to better weight management. He also discusses the pillars of lasting weight loss, which include nutrition, fasting, resistance training, optimizing supplements, stress management, and sleep. Dr. Jones addresses the balance between prolonged fasting and maintaining muscle mass, highlighting the importance of proper calorie intake and protein consumption. Finally, he defends Dr. Fung's stance on exercise and calories, acknowledging him as a pioneer in the field of obesity and hormonal basis of weight gain. In this conversation, Dr. Jones and Jonathan discuss the role of insulin in weight loss and the importance of resistance training. They explain that while short-term weight loss is primarily about calories, long-term weight loss is influenced by hormones, specifically insulin. They discuss the impact of insulin on metabolic rate and hunger levels, as well as the weight loss plateau that many people experience. They also provide advice on getting started with resistance training, whether at a gym or at home, and emphasize the importance of maintaining muscle mass for overall health and longevity.