What is rucking? Understanding the fitness trend taking the internet by storm.

It’s not unusual for fitness equipment, trends, and workouts to mimic everyday movements or activities. The stair climber machine at many gyms, for instance, is not much different than the flight of stairs we take on our way into the office. The treadmill provides the same opportunity that walking across the parking lot offers; and swimming or rowing a boat works many of the same muscles that weightlifters target with dumbbells and barbells.

Rucking falls into that a similar category of fitness because a version of it is something that many of us are doing every day – often without realizing. Examples include trekking across a college campus with a backpack full of textbooks; slinging a bag of groceries over a shoulder as we carry them from the store to our car; or strapping our baby or small child to our back before going for a family walk or hike.

Here’s what rucking is, how it got started, and how you can safely participate in the practice.

What is rucking?

Originating as a military training exercise that required soldiers to march long distances carrying rucksacks (heavy backpacks) over rugged terrain to help them build endurance and strength, rucking is not much different today.

Named for the rucksacks that the soldiers wear, rucking is also sometimes called tabbing or yomping and consists of weighing down a backpack or strapping on a weight belt as one goes about a hike, walk, or run. In this way, “rucking combines cardiovascular exercise with strength training,” says Austin “Ozzie” Gontang, a licensed psychotherapist and the director of the San Diego Marathon Clinic.

He explains that one’s backpack (or fanny pack!) can be weighed down with just anything heavy: a hefty rock, canned goods, a couple of bricks, or a few thick books. Even a dumbbell or two does the trick. “Sometimes people buy weight plates that fit into designer rucksacks,” he adds.

Along with using weights, “when rucking, you can also increase your workout by the locations and terrain you choose,” says Gontang. For instance, walking or hiking uphill or traversing across rocks up staircases can improve results.

Such simplicity and flexibility are among the top reasons so many people – including famed restaurateur Guy Fieri – are drawn to the increasingly popular fitness trend. In fact, Fieri reportedly lost 30 pounds by rucking frequently.

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What are the benefits of rucking?

Indeed, weight loss and healthy weight management are a top health benefit of rucking. “An average person burns about 125 calories on a 30-minute walk, but throw on a rucksack, and, depending on your weight and speed, you can burn about 325 calories on the same walk,” says Dr. Michael Fredericson, director of the physical medicine and rehabilitation division of Stanford University. “Rucking can burn two to three as many calories as just walking.”

Gontang says that rucking is also a terrific way to build endurance and enhance your cardiovascular and respiratory fitness. “Rucking puts your body into the ideal fitness zone – around 60-70% of your max heart rate,” echoes Fredericson, “And research shows that carrying heavy loads over complex terrain increases heart and respiratory rates, indicating elevated cardiorespiratory demands.”

He points to a Journal of Strength and Conditioning Research study that shows that rucking can also strengthen the same muscles impacted by squats, push-ups, and sit-ups. Along with building lean muscle mass this way, “core and whole-body vibration exercises combined with rucking can improve trunk stability and reduce muscle sensitivity – potentially decreasing the risk of low back pain and other musculoskeletal injuries,” says Fredericson.

Rucking may even improve thinking and concentration as a 2024 study found that cognitive function increased in participants who went on a ruck march.

Is rucking safe?

Despite so many benefits, Gontang says there are some risks to be aware of when rucking. For instance, carrying too much weight or an unbalanced load can put stress on your shoulders, spine, knees, and other joints. “This can lead to lower body, lower back, shoulder, or neck pain,” echoes Fredericson.

When rucking, it’s also possible to strain muscles or tendons, to increase your risk of heel pain or conditions such as plantar fasciitis, or to fall and become injured.

Gontang cautions that such injuries are often caused through “improper form or carrying excessive weight.” He says that failing to ensure your rucksack or backpack rests snugly against your straight back or not wearing proper footwear can also cause issues. “Think of your shoes as your foundation –  they need to support you through every step,” he advises.

“Posture is everything,” he adds. “Keep your body upright by thinking tall and steady and avoid bending at the waist or collapsing your chest – your head should be up with your eyes on the horizon.”

Fredericson recommends increasing the amount of weight in the backpack and distance traveled gradually after starting with a light load. “Always listening to your body and warm up before each session,” he adds. “Consult a healthcare professional if you have any pre-existing conditions and make sure to always have enough water and let someone know your route when rucking in unfamiliar areas.”

This article originally appeared on USA TODAY: What is rucking?