Based on military training exercises, boot camp fitness routines burn calories, build muscle and challenge the body with an intense aerobic workout. What’s more, its built-in camaraderie can stimulate people bored by sweating solo because it gives them the chance to exercise with friends—or make new ones, suggests fitness expert Pete McCall, an exercise physiologist with the American Council on Exercise (ACE).

But not all boot camp fitness programs are equal. Some focus on strength, others on cardio. Intensity also varies, and if you haven’t gotten much exercise lately you should try a beginner-oriented program. “Be honest about your skills and abilities and work at the appropriate fitness level,” McCall says. “It’s better to avoid a drill or do a modified version of an exercise in order to avoid an injury.”

McCall also suggests you take time to investigate a boot camp program before buying a membership. Specifically, look at its exercise plan and the instructor’s qualifications, and check online for testimonials. Also, ask for a free trial.

Remember, there’s nothing better than personal experience to tell if a plan is right for you!