CrossFit is a strength and conditioning program that combines a number of activities, including weightlifting, sprinting, powerlifting, rowing, gymnastics, plyometrics, and medicine ball training. The sport was originally designed to train police officers, special military forces, martial artists, and specialty athletes, but it has since been expanded to include men, women, and children of all ages and skill backgrounds. Program sponsors claim that CrossFit aims to be “broad, general, and inclusive.” They claim that the skills needed in specialty activities, such as police work and professional football, are different in degree, not in kind, from those needed by the ordinary person in his or her daily life. The name CrossFit is a registered trademark of CrossFit, Inc., incorporated in the state of California.


The stated purpose of CrossFit is to “increase work capacity across broad time and modal domains.” The program attempts to help participants achieve the maximum possible level of achievement in every physical aspect of their lives. This reflects the belief of founder Greg Glassman that the best measure of a person's overall health is not any one medical measurement, such as blood pressure), or combination of them, but one's overall fitness. Training for a healthy life demands that a person push his or her body to achieve the highest degree of physical fitness possible.


CrossFit was founded in the 1980s by former high school gymnast Greg Glassman and his then wife, Lauren. After graduating from high school in 1974, Glassman took a job as a physical trainer at the Pasadena, California, YMCA, where he worked with professional athletes, emergency responders, and other specialized athletes, as well as with the general public. He was somewhat surprised to find that many of his supposedly well-trained clients were lacking in some skills that might be essential in their lines of work. Over time, he developed a series of workouts that became the basis of CrossFit. These exercises combined traditional body building exercises, such as curls and raises, with high intensity aerobic exercises, such as sprinting. Glassman was convinced that this combination of exercises provided the key to helping an individual reach his or her maximum physical fitness.

Glassman built his first formal CrossFit gym in his garage in Santa Cruz, California, in 1995. The same year, he was hired to train members of the Santa Cruz police department in his new approach to physical fitness. CrossFit grew exponentially, from 18 affiliated gyms in 2005 to more than 2,000 affiliated facilities in 2011. By 2017, the number of facilities had increased to more than 13,000. A turning point in the company's growth was the establishment of its first Internet site in 2001. Individuals who would otherwise never have heard of CrossFit learned about the program on the Web and found out about the exercises promoted by the program. CrossFit not only operates its programs through its affiliate members, but additionally, the company encourages individuals to construct their own home gym that contains all the equipment needed to participate in the program.


Women train at Ross Valley CrossFit in San Anselmo, California, March 2014. CrossFit is a program that combines weightlifting, sprinting, powerlifting, rowing, gymnastics, and other such activities for a full-body workout.

Women train at Ross Valley CrossFit in San Anselmo, California, March 2014. CrossFit is a program that combines weightlifting, sprinting, powerlifting, rowing, gymnastics, and other such activities for a full-body workout.
(Justin Sullivan/Getty Images)

CrossFit exercises can be performed in two different contexts: at affiliated facilities, where training is conducted under the supervision of a trained and licensed instructor, or in the privacy of one's own home. The company recommends that home training be guided by the skill level of an individual prior to participation in the program. Thus, some people will be able to begin immediately on exercises recommended by CrossFit, whereas others will have to learn those same exercises at a slower pace over a period of time.

The core of the CrossFit program is the Workout of the Day (WOD), a set of exercises recommended by the company at its affiliate facilities and on its website for each day of the year. Every day, the WOD consists of a different set of exercises calling on the three major areas of exercise. These exercises include activities such as back squat, ball slam, bench press, cleans, deadlifts, dumbbell moves, hand stands, jump-rope skills, kettle bell exercises, medicine ball work, presses, pull-ups, push-ups, rope climbing, rowing sprinting, and wall balls. One or more days a week are designated as rest days on which no exercises are to be performed. A typical WOD might be the following:

Because the skill emphasis (e.g., strength, speed, endurance) differs each day, the next day's WOD might look very different from the previous one.


No official count of the number of CrossFit participants is available but the program is in use at more than 13,000 facilities worldwide. It is also part of training programs operated by a number of law enforcement agencies, fire departments, and military agencies. CrossFit has a special program for children and young adults ranging in age from 4 to 17. The program is divided into age groups that include Buttercups (ages 4–6), Puppies (ages 5–8), Pack Members (ages 9–11), The Porch (ages 10–12), and Big Dawgs (ages 13–17).


The main aspect of preparing for CrossFit activities is assessing one's current level of physical preparedness. Some individuals have strong backgrounds in the type of exercises included in the WOD and can begin those workouts without further preparation. Other individuals must begin with simpler exercises to prepare for the WOD on a regular basis.


The personal equipment needed for CrossFit is relatively simple, consisting of items such as weightlifting shoes, a lifting belt, lifting straps, knee wraps, wrist wraps, elbow wraps, gloves, and items needed for specialized activities, such as devices used to hold a bar while performing an exercise. The range of equipment needed to perform the WOD, however, is long and expensive. A partial list of equipment includes items such as:

Lifting a barbell or other object from the floor to the shoulders in one motion.
Small parallel bars similar in shape, but smaller in size, than parallel bars used in gymnastics.
Any exercise designed to improve muscle power by repeated and rapid stretching, followed by contraction, such as jump training.
A medical condition resulting from the rapid breakdown of muscle tissue associated with vigorous exercise.
Workout of the Day (WOD)—
A set of exercises recommended by CrossFit for participants to complete each day. The WOD is posted on the company's website daily.

Fitness clubs generally have all or most of this equipment, so anyone can take part in CrossFit exercises at these facilities. The organizers of CrossFit have attempted to simplify this list to make it possible for individuals to build their own home gym.

Training and conditioning

Because CrossFit is a training and conditioning program, no special preparation is needed to participate in the activity. People with little or no background in exercises used in the WOD will need to become familiar and more skilled in the basic training exercises at a slower rate than those who already have background in the skills.


CrossFit exercises place severe stress on all body systems, raising the health risks associated with the program. These risks range from shoulder separations to sprained wrists or ankles, to bruises, concussion from falls, and an increased risk of cardiac events. CrossFit officials acknowledge the risks associated with the program and state that individuals concerned about those risks should not participate in the program.

An example of the risk associated with some CrossFit exercises is rhabdomyolysis, a condition resulting from the rapid breakdown of muscle tissue associated with vigorous exercise. Muscle fiber components (myoglobin) produced during breakdown enter the bloodstream and may cause damage to the kidneys. A U.S. sailor who experienced rhabdomyolysis after a CrossFit workout successfully sued the company for US$300,000 for his injuries. Although the risk of rhabdomyolysis has been an ongoing concern for CrossFit, a 2013 paper revealed no cases of this condition. Instead, the highest risk injuries involved the spine or shoulders.

The injury rate established in a 2013 research paper was calculated to be 3.1 injuries per every 1,000 of CrossFit trainings undertaken. Health risks associated with CrossFit exercises are of sufficient concern that the company established its own health insurance unit, CrossFit Risk Retention Group, a self-insurance agency to deal with injuries associated with the conditioning program.


During the first decade of the twenty-first century, CrossFit was one of the most successful conditioning and training programs in the world. Relatively little formal research had been done on the CrossFit program. One important exception is a 2010 study conducted by the U.S. Army of 14 military athletes who participated in a CrossFit program for 8 weeks. The study found that all participants made significant improvement in their ability to work at various exercises, participants who were weakest at the outset of training made the greatest improvement, and participants made gains in virtually every measure of fitness. By 2014, however, researchers had begun questioning the risks involved in CrossFit training. Several studies published in 2017 identified males and those with previous injuries as at the greatest risk for injuries during training, but indicated that injury rates were comparable to those of participants in Olympic weightlifting, distance running, and many team sports.



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American College of Sports Medicine (ACSM), 401 W. Michigan St., Indianapolis, IN, 46202-3233, (317) 6379200, Fax: (317) 634-7817, .

American Council on Exercise, 4851 Paramount Dr., San Diego, CA, 92123, (858) 576-6500, (888) 825-3636, ext. 782, Fax: (858) 576-6564, .

CrossFit, Inc., 1250 Connecticut Ave. NW, Washington, DC, 20036, (202) 449-8533, customerservice@crossfit. com, .

David E. Newton, AB, MA, EdD

  This information is not a tool for self-diagnosis or a substitute for professional care.