#59 - The Three Levers: Andy Blow on sweat, sodium, and smarter hydration

Andy is solving the “guesswork problem” in endurance performance: athletes lose wildly different amounts of fluid and sodium, so generic hydration advice leads to dehydration, cramping, GI distress, or even hyponatremia—and performance falls apart in the heat and over long durations. In today’s conversation Andy Blow explores why hydration and fueling are never one-size-fits-all—and how understanding your sweat losses can transform performance in long or hot training and racing. He and Dr. Wells break down sweat physiology, heat adaptation, and why you can “do everything right” yet still struggle if your sodium and fluid strategy doesn’t match your body. Andy also shares practical guardrails for drinking, electrolyte replacement, and carbohydrate intake, plus the simple “three levers” framework that helps athletes execute better under stress.You will learn why humans sweat (and why it’s a performance superpower), and how sweat is linked to blood plasma and electrolyte loss. You will learn the real-world range of sweat sodium losses (and why that range matters more the longer/hotter the event). You will learn how heat acclimation changes sweating, blood volume, and tolerance over ~2 weeks. You will learn practical hydration guidance (short sessions vs long sessions) and how to avoid overdrinking/underd rinking traps. You will learn the emerging best practices for endurance fueling—from ~30g/hr up to 90–120g/hr for high-output athletes who can tolerate it.You will discover that your “hydration problem” is often a sodium + fluid mismatch—and that getting those two numbers closer to your personal losses can be “night and day” for performance in the heat. Andy helps listeners solve the challenge of finishing long/hot sessions strong—without bonking, cramping, or having the day ruined by avoidable hydration and fueling mistakes.