NEW YORK — Travelers have no interest in lugging their luggage anymore.

They don't have to, according to experts.

A combination of consumer demand, design modifications and innovative materials has allowed manufacturers to produce smaller, lighter and ergonomically friendly products, says Alan Krantzler, vice president of Tumi luggage brand's product management.

"The No. 1 trend in the industry right now is about lightweight," he says.

The driving factors, he says: an aging population who find it difficult to pull around burdensome, easily tipped bags; airline fees, including charges often for any checked bag at all; and the desire for business-leisure crossover items.

"People want a carryon that could be a weekend bag, a gym bag and be able to put a computer in it," says Krantzler, who also oversees merchandising. "People are looking to spend money smartly. They don't want to give up quality but want value."

Options include hard-shell plastic or soft foam-frame bags — Tumi Light bags, for example, are made from the same EVA foam as flip-flops.

"What affects weight is more the components of the bag, the fabrics, how it's made," says Krantzler, "it's not really about the shape."

Polycarbonate plastic is a much lighter version of those practically indestructible suitcases of a few generations ago.

"The fashion, lightweight, hard-side bag is a big thing in Europe," says Macy's home fashion director Stephen Cardino.

It has potential to catch on in the U.S., Cardino says, but Americans also do seem to like their softer bags, knowing they can always shove in that extra sweater.

"People don't buy luggage sets anymore. It's more like furniture shopping, a piece from here and a piece from there."

Jeff Herold, founder of the Train Reaction luggage system, says that for his bags he found a light but strong nylon fabric known as Invista. While the suitcases themselves are light, he wants you to stuff them full. It helps with the nontraditional weight distribution that puts the bulk up against the telescoping handles.

Tumi's Krantzler says he favors a four-wheel suitcase, which is "driven" more like a grocery cart than dragged,. "There's a lot less stress on the wrist — the bag can be upright all the time. The wheels spin independently."

As a frequent flier, Krantzler also likes the flatter messenger-style bags for his laptop — a style that often seems to satisfy TSA screeners without taking the computer out of the bag.