If you're bored with your usual workout routine, shake it up with one of these fast-growing alternatives! You don't have to be a gymnast or circus performer to get started. These exercise methods attract people of all ages, abilities, and backgrounds.

Yoga

Football players do it; grandmothers do it. From the brisk pace of power yoga to the lengthy poses of Iyengar yoga, there's a style for you. The pace and content of classes can vary widely from instructor to instructor; however, no matter the class, you're sure to improve flexibility, balance, and strength, all while gaining a clearer head and discovering muscles you didn't know you had.

Pilates

The secret of Pilates lies in the simultaneous flexing and stretching of muscles, which promotes a lean, deceptively strong physique. Mat Pilates, the most common form and where movements are done mostly on the mat, requires little or no equipment. But mat movements represent only about 25 percent of the Pilates regimen. Other types of Pilates might be done using resistance bands or special spring-loaded machines and one-on-one instruction, which doesn't come cheap. Many gyms feature mat classes with qualified instructors.

Tai Chi

The "moving meditation" of tai chi can help people who suffer from arthritis and diabetes, and yields a host of other health benefits: increased strength, coordination, and range of motion. The lowest impact of the exercises listed here, tai chi stresses fluidity and balance through repetition of forms—smooth, flowing movements that work all of the major muscle groups and joints, and sometimes is done outdoors. Classes often begin and end with a brief meditation.

Boot Camp

Sometimes you just need guidance from others to get through a workout, and old-school exercises are easier to stomach when 30 other people are enduring them alongside you as a guy in camouflage pants barks orders. Expect 45 to 60 minutes of jumping jacks, push-ups, lunges, marching in place, and crunches—without much sympathy. Actually, some classes aren't so hard core and allow you to work at your own pace! Try sitting in on a class before you start. Many gyms offer some version of this class.

Roller Derby

If you're not afraid of a few bumps and bruises, lace up your skates and hit the track. In roller derby, two five-person (often all-female) teams skate in formation and try to prevent their opponent's designated scorer from passing their own teammates. Clubs and leagues have sprouted up around the United States.