One-bag, carry-on, light travel tips, techniques, and gear

An orthopedic and sports medicine specialist says choose carefully if you’ve got a big load to lug:

Design is more important than you think. If you’re hauling a heavy load, look for a bag that carries most of the weight near your spine, or the center of your body, which means less stress, (Dr. Robert) Pedowitz says. His top recommendation is a dual-strap bag.
Messenger bags are OK if you carry most of the weight on your butt as opposed to one side. Large purses and bags that you carry on one shoulder or by hand are the worst offenders, Pedowitz says. “They can strain your hand, wrist, elbow and shoulder,” he says.

I believe the magic number for normal- and small-framed people is around 15 pounds. Exceed that weight for long (on your shoulder) and you’re in for some real discomfort unless you have wheels or a real backpack with with a good suspension system. The story referenced above mentions college students who struggle with 20-pound laptop and messenger bags. Portable computers are indeed the chief offender these days; they always add 4-12 pounds. If you must travel with one you’ll be hard pressed to to keep your total carried weight much below 20 pounds.