Holiday flights don’t have to flatten your energy or your immune system. Dr. Robert Lufkin breaks down what actually happens to your body at altitude—lower oxygen, desert-dry cabins, stalled circulation—and shares a clear plan to stay sharp before, during, and after you fly. Instead of white-knuckling through recycled air and jet lag, you’ll learn how to turn the cabin into a controllable environment and land clear, not crushed. We start with the physiology: why pressurization strains mitoch...