The Scientific Reason Boot Camp Workouts Are So Good For You

Boot camp-style workouts have been around for decades. But now they come in many shapes and flavors—from bridal boot camps designed to tone people up for their nuptials to “prison-style workouts” taught by people who were formerly incarcerated.

Yet most boot camps share a few important things in common. They combine a series of calisthenics, like pushups, lunges and squats, with running, jumps and other high-intensity aerobic movements that are modeled loosely on military methods for whipping new recruits into shape. Most use forms of body-weight training, but some incorporate equipment—whether real-world items like tires or park benches, or traditional gym gear like kettlebells.

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The exercises that comprise boot camps “are designed to work the upper and lower body and core, so it’s a comprehensive workout,” says Dr. Edward Laskowski, a professor and co-director of Mayo Clinic Sports Medicine who is currently conducting research on boot camp workouts. “They’re similar to CrossFit workouts but with less equipment,” adds John Porcari, a professor of exercise and sport science and program director of the clinical exercise physiology program at the University of Wisconsin, La Crosse.

What makes boot camp workouts so unique is that they emphasize total-body functional training, Porcari says. While traditional gym workouts using weights and machines may improve strength, he says that functional training better prepares the body for real-world activities like climbing stairs and lifting groceries. “You’re learning to carry your body around, not a bunch of weights, which I think is a great thing,” he says.

These workouts also burn calories and improve fitness. One of Porcari’s studies found that the average boot-camper expended about 10 calories per minute during the training—not quite as much as someone would burn running at a fast pace, but about as much as one would while cycling or swimming.

Another benefit of boot camp workouts: Most mix periods of very vigorous activity with short rest breaks, and so are considered forms of high-intensity interval training (HIIT), Porcari says. HIIT workouts maximize fitness gains in the shortest period of time. Porcari’s study found that during bootcamp workouts, people’s average heart rate hit 77% of maximum, which is within the range needed to improve physical fitness, according to the American College of Sports Medicine. But their heart rates ranged as high as 91% of max—well above the 80% level needed to qualify as HIIT.

It’s important to note that all of these numbers are variable. While some boot camp workouts emphasize cardio and aerobic fitness, others focus on strength training or weight loss. Some are indoors and use rowing machines and other equipment, while some take place in empty parking lots, woods and parks, relying only on a person’s body weight for resistance. But nearly all boot camp workouts incorporate the elements and provide the benefits listed above. And like other group fitness classes, the camaraderie people experience during boot camp workouts can keep people engaged and motivated, Laskowski says.

Neither age nor weight are disqualifiers when it comes to boot camp workouts. “If you stay within yourself and have a good instructor who can modify the training to your ability, I think anyone can do them,” Porcari says.

But he also warns that some programs don’t put much emphasis on proper form or supervision. “I’ve seen some with 30 or 40 participants and just one instructor,” he says. With so little oversight and one-on-one coaching, a person’s form may break down and injuries may occur.

Laskowski adds that people with joint problems or those who haven’t exercised in a while may want to build up a foundation of strength and physical fitness before attempting an intense boot camp program.

But if you’re in shape and confident that a class is within your training abilities, boot camp workouts are a fun, effective way to train your entire body.