CrossFit uses Olympic weightlifting, kettlebells, gymnastics rings, pull-up bars, and many calisthenics exercises. CrossFit athletes run, row, climb ropes, jump up on boxes, flip giant tires, and carry odd objects. They can also bounce medicine balls against the floor or a target on a wall.

CrossFit workouts often call on athletes to move large loads long distances quickly. Many CrossFit gyms use scoring and ranking systems, transforming workouts into sport. ^[2]CrossFit responds to criticism that its program is too intense by citing an essential element of its methodology: workouts should always be individually scaled and varied.

CrossFit seeks to unify health and fitness. It defines health as sustained fitness. CrossFit’s prescription for achieving this fitness is constantly varied high intensity functional movements. CrossFit says fitness can be graphed in three dimensions, with duration of effort on the x-axis, power on the y-axis, and age on the z-axis. At each duration, power capacity is averaged across a variety of modal domains (skills and drills). CrossFit says it increases work capacity and speed in these domains by provoking neurologic and hormonal adaptations across all metabolic pathways. CrossFit says it is building a technology of human performance through careful definition of terms, constant experimentation and precise measurement by using a force, distance and time approach, rather than a molecular one. CrossFit views such measures as lactate threshold and vo2 max as correlates or components of fitness, but says measuring actual performance in specific workouts is of far greater interest to athletes and coaches. [5] CrossFit was introduced to the academic exercise physiology community at a meeting of the American Society of Exercise Physiologists in April, 2009. ^[3]

On diet, CrossFit advocates eating meat and vegetables, nuts and seeds, some fruit, little starch and no sugar at levels that support exercise but not body fat. Many CrossFitters follow the Zone Diet or the Paleolithic diet.^[4]

CrossFit adaptations include programs tailored for children, pregnant women, seniors, football players, military special forces candidates, and endurance athletes including triathletes, runners, swimmers and rowers. Most CrossFit gyms also offer "On Ramp" or "Elements of CrossFit" introductory classes for beginners. Some Crossfit athletes perform the "Workout of the Day" posted at the CrossFit website and never visit a CrossFit gym. Others formulate their own workouts based on CrossFit's principles. In 2007, the United States Marine Corps began a shift in its physical training program. The emphasis is moving away from aerobic training and toward more combat-oriented "functional fitness training" by incorporating CrossFit principles. Many U.S. and Canadian police and fire departments, U.S. Army Special Forces and the Canadian Forces now base some of their physical training on CrossFit principles.^[5] Official CrossFit affiliates operate at the United States Military Academy at West Point, at more than 40 U.S. military bases worldwide and at the Royal Danish Life Guards headquarters in Copenhagen, Denmark. CrossFit is also being adopted by a growing number of U.S. and Canadian high school physical education teachers and by teams at both the high school and college level.^[6]

CrossFit Inc.'s affiliate model rejects franchising and requires few start up expenditures. CrossFit Inc. headquarters certifies CrossFit trainers, approves applications for gyms to become affiliates, licenses use of the CrossFit brand to affiliates and publishes "The CrossFit Journal." But Crossfit Inc. headquarters does not share in revenue from membership fees charged by affiliates. Affiliates pay CrossFit Inc. headquarters only an annual affiliation fee of $500 - $2,000. Affiliates retain all the revenue from membership fees they establish themselves. Affiliates may also develop their own programming and instructional methods. Monthly membership fees for clients at CrossFit affiliates generally range from $85 to $300, with $150 a fee often charged. Many affiliates feature small group classes that allow for individual coaching. Classes often include a warm up, a skill development segment, and a high-intensity timed workout that lasts 10 to 20 minutes. CrossFit Inc. headquarters says this de-centralized model, which shares some common features with open source software projects, allows best practices to emerge from a diversity of collaboative approaches. The workouts posted on the main CrossFit website are just one expression of the CrossFit concept, says CrossFit headquarters. ^[7] The privately-held company was described as "hugely profitable" in a 2009 CrossFit Journal article that estimated annual revenue from certification seminars at $6.41 million and indicated that annual affiliation fees may amount to $1.85 million. No figures were provided for subscription, merchandise or sponsorship revenue.^[8]