What's your advice on exercising during a 72 hour fast?

For a 72-hour fast, keep exercise cautious and prioritize hydration. The fat-burning approach described is not a blanket recommendation for prolonged fasting, and fasted training can affect how much energy you have for exercise. 1

• 20–60 minutes of high-intensity exercise, then moderate cardio: This sequence was described as a way to deplete glycogen and shift toward more fat oxidation when exercising fasted; the speaker also qualified it with “if” it is safe for you. 2
• Caffeine: It may feel more potent when fasted, and caffeine before exercise can support alertness or performance, though individual responses vary. 3
• Water and electrolytes: Drink water, and consider electrolytes such as LMNT during exercise; the discussion emphasizes that hydration and electrolytes matter for physical performance. 4