Founded in 2000, it reached it's peak in the last 5 or 6 years having over 10,000 "boxes" open. It is practiced with everyone from stay at home moms to professional athletes and military personnel. It is a hot topic for many, mostly people being completely with it or completely against it. I personally, am in the middle. I love the fact that it gets people motivated to get in better shape, doing weight lifting exercises as well as olympic lifts. I like that it is a cross training format that incorporates almost all the movement types there are; lifting weights, plyometrics, calisthenics, running, biking, swimming, rowing, kettlebell, gymnastics and high intensity interval training. It keeps members coming back with so much variety, competition and comradery.
Like all training, if done wrong, could be dangerous or even deadly. Crossfit has gotten a bad rep for the many injuries that have happened to their participants. MD Scott Miller describes Rhabdomyolysis, "when muscle is damaged, a protein called myoglobin is released into the bloodstream. It is then filtered out of the body by the kidneys. Myoglobin breaks down into substances that can damage kidney cells." Uncle Rhabdo, as some opponents of crossfit call it; while still very rare, can happen and has happened to crossfit participants and collegiate football players more often than just about all other forms of exercise practiced by the masses. It's generally caused by going above and beyond what your body is capable of, doing many many(as in like 100's) of reps which causes an extreme breakdown of muscle tissue down into your circulatory system, which can't be filtered by the kidneys. It may lead many ugly physical symptoms and conditions including kidney failure.
Like all instructed exercise, CrossFit is all based on the trainer(s). NO WHERE in this country, except Washington D.C., does it legally require people to be certified for personal training. Getting certified to teach CrossFit only requires 14 hours of education and $1,000 bucks. Anyone with some cash and a free weekend can train people in the most dangerous weightlifting movements performed; snatches, clean & jerk, hang cleans, power cleans and Deadlifts. The WTF homepage has all the NCCA accredited organizations and CrossFit isn't one of them.
Don't get me wrong, some people already have an educational background, going well beyond one weekend of learning. There are many professionals in the field that have taken CrossFit up for themselves and coach others, even people I graduated with. The people I graduated with also know the importance of safety. Repetition schemes can make or break a person's programing and training. For example, the "Fran" workout goes for 2 exercises in each set, barbell thrusters(95 lbs) and pull-ups. First set is 21 reps each, then 15 reps each, finishing with 5 reps each. This workout is what many CrossFitters consider to be a benchmark of fitness. This workout doesn't count for the strength and endurance of the person working out, meaning if someone's thruster max is 120, there is no reason they should be doing 80% of their 1RM(rep max) for 21 reps. When you do any sort of lifting that is either A) technical or B) heavy(comparatively) then the reps should be much lower than 21 or 15. This workout could be a better workout/test if it including individualized weights, like half of body weight or 50% rep max and not so many reps with a technical lift like the barbell thruster. When doing more technical lifts, muscles begin to fatigue, especially in beginners. When muscles fatigue, form breaks down. Which results in A) muscles other than the targeted ones get recruited to pick up the slack and B) chances of injury increase dramatically.
I always say train for what you want to do or accomplish. When it comes to CrossFit it's no different, people like Rich Froning train year-round to compete in the CrossFit Games. The thing is, they don't train by doing WOD(Workout Of the Day) twice a day, they train systematic progression programmed the way most successful athletes train. When training you are activating hormonal pathways, two of which are mTOR and AMPk. Past research shows mTOR being activated much more during strength training, and AMPk activated more during cardiovascular training. Although recent research by Lundberg TR1, Fernandez-Gonzalo R, Tesch PA shows aerobic exercise paired with resistance exercise with a 15 minute rest between; giving all the benefits of each with the exception of concentric torque being increased after resistance exercise alone.
CrossFit has a very diverse amount of exercise types with a great emphasis on compound movements like power/olympic lifting, which can make a fantastic way to exercise. Like all exercise; the training is only as good as the instructor and programming.
