Find a spot where you can reach down and touch your toes. Stretch and stand on your tiptoes and reach for the sky. If you're trapped in your seat, adjust your posture, regularly shifting weight to different parts of your body. If your feet don't touch the floor, build yourself a foot rest with a piece of luggage or stack of blankets. And use one of those U-shaped, neck support pillows if you like to sleep while flying.
Luggage can be a killer.
Even carrying a ten-pound bag, keep in mind the average laptop weighs eight pounds, from a ticket counter to a departure gate can put major stress on your spine. Feldman says use a luggage cart or luggage with wheels. When you pick up checked baggage from a carousel, don't grab and twist as most people do. Get in front of the bag at a slight angle, pick it up and immediately set it down. There are hotel beds out there waiting to hand you a sleepless night.