Frequent fliers with long layovers can now do workouts at airport gyms--something that could be especially appealing to travelers getting on or off cramped planes. This is due to wellness trends, as well as trends about major US airports becoming destinations in their own right.

This is shown in the soon-to-open Roam Fitness Gym at the Baltimore Washington International Airport. Aside from gym equipment, there will be an attendant who will monitors guests' flights and notify them if there is a delay. There is even free luggage storage, options to rent workout attire and showers. Fees will range from $40 to $175 a month.

"A lot of people coming from the West Coast taking red-eye flights are going straight to their business meeting but they land at 6:30 in the morning. They can't check into their hotel yet... so it just gives them the opportunity to clean up before they head to that meeting," said ROAM Fitness CEO Cynthia Sandall, reports ABC News.

The GoodLife Fitness' gym at Toronto airport which opened in 2014 had a 33 percent increase from when it started. The concept of gym in airports was initially planned for international travelers and others with long layovers, but survey showed that many other travelers wanted to do a workout before or after landing.

The concept may not work everywhere, however. The American College of Sports Medicine task force on healthy air travel, says the gyms' successful operation may depend on the location. He thinks they may be best suited for hubs with long layovers. 20 more such gym airports are planned to be built by year 2020, possibly at O'Hare, Minneapolis, Portland, Seattle.

Wellness trends like Yoga rooms and walking tracks have also been successful in airports, according to USA Today. In fact, 2 Yoga rooms in San Francisco airport have been opened. Restaurant serving healthier food options are also in vogue, like The Plant Cafe, where everything is made with local and organic ingredients. New vending machines offering gluten-free, organic and sugar-free snacks are offered at Napa Farms Market, Joe & the Juice.

Other amenities planned as major airports are planned to become venues in their own right include more fine dining restaurants, shopping stores and movie theaters.