Ate too much over the holiday? Book your vacation here

There are a number of jogging and walking tours available in the British capital.Jae Hong/The Associated Press

My laptop is currently balanced on a Christmas pudding-shaped paunch that would make a portly hobbit proud. But I'm not a hobbit (despite the hairy feet) and, rather than a calorie-burning dragon quest, I'm mulling a move to a nearby side table for some chocolate-covered almonds.

We all face a crossroads in January: either buy pants with elasticized waists or tackle our seasonally skewed fitness fall-off. But raising your heart rate doesn't have to mean fun-free military discipline. Here are some belt-slackening vacation strategies that promise pleasure as well as sweat-triggering workouts.

For those who haven't mastered running and map-reading in unison, several cities offer guided jogging options where you can see the sights, burn off some eggnog and get the lay of the land with fleet-footed locals.

Consider Paris Running Tours (parisrunningtour.com). Their Right Bank option is especially recommended for La Ville-Lumière first-timers – it weaves past leading landmarks from the Eiffel Tower to the Musée d'Orsay. Jogs last from one hour, cost from around $125 a person and rates include brag-worthy photos of you en route.

There are similar operators in London (cityjoggingtours.co.uk), Barcelona (runningtoursbarcelona.com) and Cape Town (runcapetown.co.za). For guided gallops in other destinations, peruse gorunningtours.com.

But if you really want to tighten those buns – or at least forget how many buns you've eaten recently – consider tackling a marathon in another country.

For a country so heavily marbled with obesity, the United States is packed with 42-kilometre races open to all-comers. The website marathonguide.com lists hundreds of runs and you can click through to register for most of them. If you're keen to work off those chocolate Turtles ASAP, there are tan-promising January or February races in Orlando, Fla., Phoenix and Sedona, Ariz.

For a more sedate pace, you can add hearty, self-navigated strolls to any trip. If you fancy company, I recommend the great-value London Walks (walks.com) plus San Francisco's Mission Trail Mural Walk (precitaeyes.org).

But if you want to crank it up with a hike or two, escape the snowy north – only after a some snowshoeing and cross-country skiing at home – and head south. It's summer down there, so you'll perspire as if you're a well-done roast potato.

Great Walks of Tasmania (greatwalkstasmania.com) hosts breathtaking guided tours in Australia's southern-most region. New Zealand is also striped with accompanied treks – I enjoyed a smashing Maori cultural hike with Whirinaki Rainforest Experiences (whirinaki.com) – and it's ideal for self-directed wanders. If you can wait, Lonely Planet's new Hiking & Tramping in New Zealand guidebook comes out in April.

If you'd rather ride a bike, your steely calves are also spoilt for choice. Peruse the Trek Travel website (trektravel.com) for tours in North America and beyond. Or look around the G Adventures site (gadventures.com) for enticing two-wheeled trundles in Cuba, Ecuador, northern Spain and the rest of the world.

If you're still pushing your turkey tummy around in a wheelbarrow by July though, try a Bulgan Trail bike tour with Bike Mongolia (bikemongolia.com). Straining through remote mountain passes, your mince pies will be a distant memory.

But if that doesn't work – or Valentine's Day chocolates push you off the wagon – take drastic action with a boot-camp vacation, typically including strict diet and exercise regimes.

Try Portugal's Algarve Luxury Boot Camp (algarveluxurybootcamp.com) or England's all-female GI Jane Boot Camp (gijanebootcamp.co.uk). There's also Mountain Trek (mountaintrek.com). With wellness resorts in B.C. and Mexico, they additionally organize fitness-focused overseas hiking vacations: the next one is to Japan in spring 2014.

Alternatively, you can start your New Year fitness drive more gently. I'm planning to restore my whippet-thin pre-Christmas frame by adopting a brisk pace to the candy bowl across the room. I may even do it twice.

OUR READERS WRITE

A great holiday would be climbing Mount Kinabalu in Borneo, highest mountain in Southeast Asia. It’s easy hiking, just long enough and has a spectacular view as a reward at the end. Kathy Ko
Why not hike the Camino de Santiago? You can walk all or part of it and stay at hotels or albergues. It’s an incredible way to discover Spain. Geoff Gibbons
Slickrock.com is a company that runs small group trips on an island in Belize. They have the best sports equipment for a super active holiday. You can sea kayak to a snorkelling spot, tie up your kayak and go snorkel, then return and go surf kayaking, then do some stand up paddle boarding and then go for a windsurf. Sue Kingston
Try fat-biking in winter through fresh powder. A lot of fun and it burns more calories too! @smallandhungry
Adam’s Peak, Sri Lanka for a spiritual and calorie burning sunrise climb. Or Rancho La Puerta, Tecate Baja: amazing wellness spa and its closer to home! @AlixScott2
Washington, DC: jog at the National Mall or Rock Creek Park, hike great falls or bike the Mt. Vernon trail to Old Town. @DCRepatriate
Pilgrimage in Santiago de Compostela? You can walk, run, or bike the way. There’s a certificate for completing it. It’s a great town to visit afterwards, too. @Chiqee
Santa Cruz for bike riding. We went last April and enjoyed the trails. I know others who ride year round in this area. @drcolinwilson
Laos or Morocco for biking, Argentina for hiking. All are great for winter travel and are not inundated with tourists. @bikehiketravel
How about a health spa, fitness boot camp and weight loss retreat? Recommend Mountain Trek in the Kootenay Rockies. @rcolthorp21
Austin, Texas is a great biking city. Recommend Lady Bird Lake hike-and-bike, but wait until the South by Southwest festival in March for your visit. @travel_smith
New Zeland is all cyclable from north to south. @Giapo
Being new to Vancouver, I learned it is easy to stick to keeping fit when you can train in picturesque settings – obviously the seawall, the Grouse Grind etc. @angelamjoyce
Cumberland [on Vancouver Island] for mountain biking and the Sunshine Coast for road biking. The Kootenays are good for mountain biking, too. There are lots of good places in Oregon as well, including Bend, Hood River and Black Rock. Portland is also good for cycling in general. @mtnbikinggirl
Road biking: nothing beats the Malahat [on Vancouver Island]! Also, mountain biking in Queenstown. Book ahead for bike rentals in Spain – I got to Madrid to find nothing left! @SaraMacAleese
Peru’s Machu Picchu; Costa Rica; or Arizona/Nevada. In Canada, snow shoe/ski resorts. There’s also cost efficient treks of Mont Blanc or if not budget conscious, how about the Great Wall of China? @tweetsbycc
Would have to suggest a hidden little gem in Ontario – Peterborough & the Kawarthas – for hiking, biking and paddling. @fionad03
Banks-Vernonia State Trail: 21 miles of paved, abandoned railroad bed. It’s a great ride! @Allison_George