Long gone are the days of vacationers lounging languidly by the pool. As of late, a week of vacation is a great time to get into shape — or at least jump-start a lagging fitness regimen. “No pain, no gain” is now a rule that applies to getting away from it all.

If you’re seeking a challenge, Bikini Boot Camp at the Amansala Resort could be the answer. Situated on the pristine beaches of Tulum, Mexico, this program has won over celebrities, reportedly including actresses Sienna Miller and Maggie Gyllenhaal. “People are definitely interested in a holiday with a purpose,” the owner of the resort, Melissa Perlman, said. And the purpose of this resort, about 80 miles south of Cancun, is to make you look better in your bikini by the end of your stay. To reach that goal, the resort offers a wide range of outdoor activities, such as kayaking and snorkeling as well as beachside exercise classes, including yoga, Pilates, and meditation. While losing fat is the goal, it’s not all hard work. Visitors will have ample time to take writing workshops and cooking courses and, of course, to sunbathe. (six-day packages, $1,945 for a shared room, $2,661 for a private room, cost includes meals, activities, and ground transportation, airfare not included, +52-984-1000-805, amansala.com)

For those energized by the prospect of exploring a far-off land, fitness goals don’t need to be left behind. Escape to Shape, a boutique traveling spa, offers health-centric getaways that span the globe. The company sets up shop in one destination for between five weeks and two months, stopping in four locations a year. Now stationed in Marrakech, Morocco, Escape to Shape will travel to Taormina, Sicily, this fall. Regardless of location, guests spend four hours a day taking exercise classes. Vinyasa yoga, Pilates, circuit training, and hiking are among the fitness options. Vacationers stay in villas or houses — trip organizers arrange the accommodations — rather than hotels, often eat produce grown in a backyard garden, and take group field trips to noteworthy sites. In Marrakech, visitors, who stay in a restored Kasbah overlooking the Atlas Mountains, can take cooking, pottery, and belly dancing electives. In Taormina, guests will live on a property that is home to a lemon orchard; fishing and hikes up Mount Etna are already on the itinerary. (Seven-night packages, $3,000, includes meals, airfare, and ground transportation, 601-818-8137, escapetoshape.com)

If a healthy escape closer to home is desired, the New Age Health Spa, situated about 120 miles north of New York City in Neversink, N.Y., is an option. New Age offers a week-long, all-inclusive vacation that offers three spa treatments. Guests can participate in a range of exercise classes, cabaret dance and kickboxing among them. There’s cerebral instruction on holistic healing, nutrition, and psychology. Leisure-time activities include dancing and flying kites. The Catskill Mountains provide the backdrop for water aerobics and early-morning climbs. Hikers can attempt to scale the Alpine Tower, a five-story wooden structure, which visitors can climb while they are tethered by safety ropes. (Seven-day packages from $2,722 for single occupancy, from $2,109 for double occupancy, includes meals, activities, and treatments, 800-682-4348, newagehealthspa.com)

However, fitness doesn’t need to be a top priority when booking a trip. If you hanker to get away from it all, though not to complete seclusion, many hotels in major cities offer clever ways to combine sightseeing with fitness. At the Andaz Hotel in London, for example, a stay includes a guided 5-kilometer run that is also a tour of the Thames River and circles the Tower of London. It is a unique way to see the historic city, especially when you add the requisite weighted kettle bells. Visitors are likely to want to head to the pub or Harrods afterward. (From $220 a night, includes guided run, +44 0207-961-1234, London. liverpoolstreet.andaz.com)