CrossFit

CrossFit, Inc. is a fitness company founded by Greg Glassman in 2000. CrossFit's exercise program is practiced by members of approximately 7,000 affiliated gyms, most of which are located in the United States, and by individuals who complete daily workouts posted on the company's (or an affiliated gym's) website.

Programming and Usage
CrossFit is a strength and conditioning program with the aim of improving, among other things, muscular strength, cardio-respiratory endurance, and flexibility. It advocates a perpetually changing mix of aerobic exercise, gymnastics (body weight exercises), and Olympic weight lifting. CrossFit Inc. describes its strength and conditioning program as “constantly varied functional movements executed at high intensity across broad modal and time domains," with the stated goal of improving fitness, which it defines as "work capacity across broad time and modal domains." Hour-long classes at affiliated gyms, or "boxes", typically include a warm-up, a skill development segment, the high-intensity "workout of the day" (or WOD), and a period of individual or group stretching. Some boxes also often have a strength focused movement(s) prior to the WOD. Performance on each WOD is often scored and/or ranked to encourage competition and to track individual progress. Some affiliates offer additional classes, such as Olympic weightlifting, which are not centered around a WOD.

CrossFit programming is decentralized but its general methodology is used by thousands of private affiliated gyms, fire departments, law enforcement agencies, and military organizations including the Royal Danish Life Guards,   as well as by some U.S. and Canadian high school physical education teachers, high school and college sports teams, and the Miami Marlins.

Business model and CrossFit culture
CrossFit, Inc. licenses the CrossFit name to gyms for an annual fee and certifies trainers. Besides the standard two-day "Level 1 Trainer Course", specialty seminars include gymnastics, Olympic weightlifting, powerlifting, strongman, running and endurance, rowing, kettlebells, mobility and recovery, CrossFit Kids, CrossFit Football (developed by former NFL player John Welbourn), self-defense and striking. Other specialized adaptations include programs for pregnant women, seniors, and military special operations candidates. Affiliates develop their own programming, pricing, and instructional methods. Many athletes and trainers see themselves as part of a contrarian, insurgent movement that questions conventional fitness wisdom; besides performing prescribed workouts, they follow CrossFit's nutrition recommendations (adopting a paleo and/or zone diet ), and favor minimalist footwear.

CrossFit makes use of a virtual community Internet model. The company says this de-centralized approach shares some common features with open source software projects and allows best practices to emerge from a variety of approaches, a contention that is disputed by some competitors and former affiliates.

History and contributors
Greg Glassman founded CrossFit, Inc. in 2000. The first affiliated gym was CrossFit North in Seattle, Washington; there were 13 by 2005 and more than 7,200 today. Coaches associated with CrossFit include Louie Simmons, Bob Harper and Mike Burgener.

Glassman retains complete control over the company after a divorce resulted in his estranged wife, Lauren, attempting to sell her share in the company. Glassman was able to obtain a $16 million loan from Summit Partners to buy out her share.

Common CrossFit equipment
CrossFit gyms utilize equipment from multiple disciplines.

Weightlifting

 * Bumper Plate - rubber bumper plates manufactured to withstand extreme stress.
 * Barbell - standardized to either 20 kg or 15 kg.

Conditioning

 * Medicine Ball
 * Plyo Box
 * Kettlebell
 * Jump Ropes

Body weight

 * Resistance Bands
 * Gymnastic Rings

Common CrossFit movements
The following is a list of movements/exercises common in CrossFit workouts, with brief descriptions.

Body Weight Exercises

 * Air squat: Athlete moves from the standing position to a squatting position with the hips below the knees, and back to standing. One-legged air squats are referred to as pistols.


 * Back extension: Using a GHD machine, the athlete moves from an L-shaped position with the head directly below the pelvis to an extended horizontal position by rolling the back and bringing the head up last.


 * Box jump: From a standing position on the floor, the athlete jumps and lands with both feet on top of a box, and fully extends before returning to the floor. Typical box heights in inches are 15", 20", 24", and 30".


 * Burpee: Beginning in a standing position, the athlete drops to the floor with the feet extending backward, contacts the floor with the chest, and then pulls the legs forward, landing in a squatting position before standing up, ending the movement with a small jump.


 * Handstand push-up: Beginning in a handstand, with the arms straight and (usually) the heels gently resting against a wall, the athlete bends the arms until the head touches the ground, and then pushes back up into a handstand position.


 * Hip Extension: Using a GHD machine, the athlete moves from an L-shaped position with the head directly below the pelvis to an extended horizontal position by keeping the spine straight and rotating at the hip.


 * Jump rope: The most common variation in CrossFit is the "double under" in which the jump rope makes two revolutions for each jump.


 * Knees-to-elbows: Hanging from a bar, starting in an extended position, the athlete raises the knees until they make contact with the elbows.


 * L-sit: With the body supported on gymnastics rings or parallettes, the athlete holds the feet at or above the level of the hips with the legs straight. This is typically held for a set amount of time.


 * Lunge: Athlete takes a large step forward, bends the forward knee until the back knee makes contact with the ground, and rises.


 * Muscle-up: Hanging from gymnastics rings or a bar, the athlete pulls up and over the rings or bar, ending with the arms straight and the hands below the hips. Variations include strict muscle-ups and kipping muscle-ups, in which momentum is created to complete the movement.


 * Pull-up: Starting from a hanging position with straight arms, the athlete pulls up until the chin is over the bar. Variations include: strict, in which no swinging is allowed; kipping, in which momentum is used to help complete the movement; weighted, in which extra weight is hung from the athlete; chest-to-bar, in which the ending point of the movement is higher, and the chest makes contact with the bar; jumping, in which the legs are used to help propel the athlete upwards; assisted, in which an elastic band allows the movement to be completed with less than full body weight.


 * Push-up: Starting in a plank position with the arms straight, the athlete lowers until the chest makes contact with the ground, keeping the body straight throughout, and making sure the elbows track straight back instead of out, then pushes back up into the plank position.  Variations include weighted push-ups and ring push-ups, in which the hands are supported just above the ground by gymnastics rings.


 * Ring dip: Starting with the body supported on the rings with straight vertical arms, the athlete bends the arms, lowering the body until the shoulder drops below the elbow, and then straightens the arms. To scale this movement, an athlete may do assisted dips using an elastic band or holding positions of the dip to increase stability and strength.


 * Rope climb: Starting from the ground, the athlete climbs a rope and touches a point at a designated height, often 15 feet.  Variations include no feet, and L-sit, in which the feet are held above the level of the hips during the climb.


 * Sit-up: Athlete moves from a supine position, with the shoulders on the ground, to a sitting position with the shoulders over the hips.  The feet are sometimes anchored.  An "ab-mat" is sometimes placed under the lower back.


 * Toes-to-bar: Hanging from a bar in an extended position, the athlete brings the feet upward until they make contact with the bar.

Distance movements

 * Rowing: Many workouts include rowing on rowing machines for distances of 500 meters to 2000 meters, or rowing "for calories".


 * Running: Typical distances range from 100 meters to 1 mile.  Shuttle runs back and forth between marks 10 meters apart are also common.


 * Swimming: Some affiliate gyms include aquatic distance exercises within workouts.

Movements with weights

 * Clean: Barbell is (or dumbbells are) lifted from the ground to a "rack position" in front of the athlete's neck.  Athlete ends in a standing position. In a squat clean the athlete receives the bar in a squatting position and stands to finish the lift. In a power clean, the athlete receives the bar in any position that is above a parallel squat.


 * Deadlift: Barbell is lifted from the ground, making sure to drive with the legs and glutes, until the athlete reaches an upright standing position.


 * Kettlebell swing: A kettlebell is swung from between the legs to eye level (Russian) or overhead (American). The kettlebell swing can be used both as an aerobic and anaerobic exercise.


 * Press: Barbell is moved from the "rack position" to the overhead position.  In a strict press (also called a shoulder press), or military press (in which the feet are together), the lower body remains stationary.  In a push press, the bar is "jumped" off the body using a "dip and drive" motion.  A push jerk is like a push press, but with a re-bend of the knees to allow the athlete to drop under the bar and receive it with straight arms.  A split jerk is like a push jerk, but one leg goes forward and the other backward when the athlete drops under the bar.


 * Snatch: Barbell is raised from the floor to the overhead position in one motion.  In a squat snatch the athlete receives the bar in a squatting position and stands to finish the lift.  In a power snatch, the athlete receives the bar in a partial squat.


 * Squat: Barbell is supported on upper back (back squat), in the rack position (front squat), or in the overhead position (overhead squat).  From a standing position with a wider-than-shoulder-width stance, the athlete bends the knees until the hips are below the knees, and then stands, keeping the heels on the floor.


 * Sumo deadlift high pull: With a wide stance, a barbell or kettlebell is lifted from the ground to a position just under the chin.


 * Thruster: A combination of a front squat and a push press: starting with the barbell in the rack position, the athlete squats (hips below knees) and then stands, driving the barbell overhead.


 * Tire flip: A large tire, lying on its side, is flipped over by lifting one edge.


 * Wallball: Holding a medicine ball below the chin while facing a wall at arm's length, the athlete squats (hips below knees) and stands, throwing the medicine ball in order to make contact with an overhead target on the wall.

CrossFit Games
The "CrossFit Games" have been held every summer since 2007. Participation and sponsorship have grown rapidly; the prize money awarded to each first-place male and female increased from $500 at the inaugural Games to $250,000 in 2011-2013. Winning the 2013 Reebok CrossFit Games now nets $275,000. Athletes at the Games compete in workouts they learn about only hours beforehand, sometimes including surprise elements that are not part of the typical CrossFit regimen; past examples include a rough-water swim and a softball throw. The Games are styled as a venue for determining the "Fittest on Earth," where competitors should be "ready for anything."

In 2011, the Games adopted an online format for the sectional event, facilitating participation by athletes worldwide. During the "CrossFit Open", a new workout is released each week. Athletes have several days to complete the workout and submit their scores online, with either a video or validation by a CrossFit affiliate. The top CrossFit Open performers in each region advance to the regional events, held over the following two months. As of 2013 there are 17 regional divisions, including 12 in North America (North West, Canada West, Canada East, North Central, Central East, North East, Mid Atlantic, South East, South Central, South West, Southern California, and Northern California), and five in the rest of the world (Europe, Asia, Africa, Latin America, and Australia). The top athletes (up to 3 of each gender) from each region are eligible to compete in the CrossFit Games.

The Games include divisions for individuals of each gender, and for a number of Masters age groups: 40-44 (new in 2013), 45-49, 50-54, 55-59, and 60+, as well as for co-ed teams comprising 3 men and 3 women. Masters competitors qualify for the Games based on performance in the CrossFit Open—there are no Masters regional events.

Ties are broken by the best individual event by the competitor, followed by second best, etc. until the tie is broken. This was needed to declare Craig Howard the winner in the Men's 50-54 division in 2013.

CrossFit communities organize local, regional and even international events, workouts and competitions.

CrossfitKids
Begun in 2004, CrossFitKids is a program for kids that is entirely CrossFit. It is designed with the development needs of children in mind, including cognitive, motor and neurological skills. It is a strength and conditioning program to help kids become lifetime athletes. Classes are fun and deliver measurable physical results. Workouts are varied and focus on functional movement. Kids will be seen running, jumping, pushing items, pulling items, throwing, climbing, and lifting themselves and weights. The purpose is to create a well-rounded athlete. All workouts focus on increasing physical competence in 10 fitness domains: Cardiovascular and Respiratory Endurance, Stamina, Strength, Flexibility, Power, Speed, Coordination, Agility, Balance, and Accuracy. There are currently over 2000 CrossFit Kids Trainers who are running programs in gyms, schools and community spaces. The CrossFitKids.com websites offers workouts, videos and articles of interest for anyone curious about the CrossFitKids philosophy or programming.

Criticism
According to Dr. Stuart McGill, a professor of spine biomechanics at the University of Waterloo, the risk of injury from some CrossFit exercises outweighs their benefits when they are performed with poor form in timed workouts. He added there are similar risks in other high intensity exercise programs but noted that CrossFit's online community enables athletes to follow the program without proper guidance, increasing the risk of improper form or technique.

Makimba Mimms, who suffered injuries while performing a CrossFit workout on December 11, 2005, at Manassas World Gym in Manassas, VA under the supervision of an uncertified trainer, claimed that CrossFit poses an elevated risk of rhabdomyolysis. He successfully sued his trainers and was awarded $300,000 in damages.

Articles on many websites criticize CrossFit for its lack of periodization, lack of quality-control accreditation standards for trainers or affiliates, and illogical or random exercise sequences.

Some publications have raised concerns that CrossFit promotes a potentially dangerous atmosphere that encourages people, particularly newcomers to CrossFit, to train past their limits, resulting in injury.

CrossFit efforts to address rhabdomyolysis
Crossfit Level 1 trainers are certified through the American National Standards Institute. Since May 2005, CrossFit has published several articles about rhabdomyolysis   in their online CrossFit Journal (which is not peer-reviewed). Three of the articles are included in the CrossFit Manual provided to all prospective trainers. In a further attempt to raise awareness of the problem, CrossFit, Inc. also used to sell "Uncle Rhabdo" t-shirts (featuring a cartoon clown dying in a humorous fashion—hooked up to a dialysis machine, with his kidneys and intestines falling on the floor).

As a point of comparison, Wilford Hall Ambulatory Surgical Center ran a medical review of USAF basic trainees with a population of 198,399 and witnessed 44 cases of exertional rhabdomyolysis. These training facilities are located in San Antonio, Texas, at Lackland AFB where temperatures in the summer months routinely exceed 100 degrees Fahrenheit; coupled with the rigors of exercise designed to push recruits to the limit. As of 2005, when Greg Glassman wrote his article on the status of rhabdomyolysis within Crossfit, there were only 5 occurrences.