Sitting for hours on long-haul flights can be rough on the body and the brain. Yet for travelers, the standard airplane layout of narrow, forward-facing seats in tightly packed cabins doesn't offer much in the way of movement.
So what if you could squeeze in a workout — or maybe even a spin or yoga class — at an in-flight gym?
That's the idea behind Transpose, a project of Airbus' Silicon Valley outpost known as A³. It has partnered with Reebok and Peloton to display (through May 19) a prototype 'flying gym' module — complete with stationary bikes, yoga mats, resistance stations and other workout equipment — at Mineta San Jose International Airport.
"For most people, the future of flight will still be on large commercial aircraft," Transpose project executive Jason Chua told CNBC.
"We're trying to allow for new types of in-flight experiences with a modular cabin architecture that allows for customized spaces that can be loaded and unloaded onto aircraft very rapidly," he added.
Beyond gyms, Transpose cabin modules can be stand-ins for spas, napping pods, gaming centers, dining areas, yoga studios, or even, as one traveler suggested, a karaoke lounge. Chua suggested that each creative design would offer new ways for airlines to generate revenue, and for brands to engage with flyers beyond standard in-flight branding.
More ways to carve out the cabin
While quick-change cabin modules may be a new idea, Transpose isn't the first to suggest using cabin space for activities that promote wellness. Back in 2002, Scandinavian Airlines (SAS) actively promoted basic stretching and exercise opportunities: On some of its long-distance aircraft, SAS attached a metal bar high on a wall in an unused space near the galley.
More recently, designers at Seattle-based Teague joined with Nike to envision a Boeing 787 Dreamliner with an interior luxuriously fitted with amenities for professional and elite college athletes. The offerings included extra-long lie-flat seats, a nutrition zone, biometric monitoring and analyzing systems, and a recovery room with massage table.
Last summer, Russian plane maker Sukhoi showed off a concept design for SportJet, a private jet for sports teams that is outfitted with special equipment and lighting. The mock-up included a variety of in-seat diagnostic devices that will test athletes before, during and after the flight, "to diagnose the physiological and psychological parameters of the athlete's functionality."
Although in-flight gyms, yoga studios and other high-flying cabin concepts for commercial airplanes are intriguing, "A lot of these concepts don't really account for the business model of air travel," said Devin Liddell, a principal brand strategist at Teague.
"They don't answer the question of how can the airline make money with that, and will someone actually pay for it," he added.
An entire cabin on a commercial plane outfitted with elliptical machines probably isn't reasonable — or realistic, said Liddell.
"But maybe you could have some seats that are mainly for takeoff and landing, and then allow passengers to move about the airplane in a different way," he said. "Or explore having whole cabins built around passengers with like-minded interests. People may pay more for that."
To help, many airlines offer instructions and encouragement for in-seat exercises on the in-flight entertainment system, in the in-flight magazines or on seat-back cards. Some, like Lufthansa, have recruited sports stars to demonstrate the moves in short videos.
Another, extremely low-tech approach comes from a Shanghai-based budget carrier, Spring Airlines, which has instructed its flight attendants to encourage passengers to perform in-flight exercises, said Raymond Kollau of AirlineTrends.com.
"Flight attendants announce over the PA that they will be demonstrating in-flight exercises — such as waving hands in the air, massaging temples, or stretching arms — and they recommend everyone do those actions as well," said Kollau. "And many passengers actually join in."
—Harriet Baskas is the author of seven books, including "Hidden Treasures: What Museums Can't or Won't Show You," and the Stuck at the Airport blog. Follow her on Twitter at @hbaskas. Follow Road Warrior at @CNBCtravel.