Your mitochondria built every heartbeat, every thought, every breath you have ever taken. They are the master variable of aging and they respond, every day, to how you move, eat, sleep, and meet the light. Get them right, and the rest of the body follows. Get them wrong, and no supplement stack will save you. In Power Up, Andrew Kain takes you inside the organelles that decide how gracefully you age. You'll meet Gerald, the retired postal worker whose mitochondrial fatigue had no name until it did. You'll learn what your body is trying to tell you long before a blood test catches up. And you'll leave with a four-foundation daily practice movement, light, food, sleep grounded in the biology your mitochondria evolved to respond to. No supplements to buy. No subscription. No guru. Just the mechanisms, and what to do with them. ANDREW KAIN, MS, DC · Book Two of the F(x) Longevity Series