In short, yes it can be, for a few reasons…but not as dangerous as you might be led to believe.
In the wrong situations, with the wrong coaches, and a person with the wrong attitude, CrossFit can absolutely be very dangerous.
1) During a CrossFit workout, you’re generally told to complete a number of strength training or endurance exercises as fast as possible, or complete as many repetitions as possible in a certain amount of time. For that reason, it’s REALLY easy to sacrifice form in exchange for finishing the workout quicker. If you don’t have somebody spotting you or telling you to keep your form correct, then you’re in trouble.
When it comes to strength training, improper form (especially at high speeds with heavy weights) is the FASTEST way to get seriously injured. If a CrossFit gym is run by inexperienced and unproven coaches – which definitely happens – then things like this happen and they happen frequently.
2) CrossFit attracts a certain type of person…namely folks who push themselves so hard they actually do bodily harm. Ask any CrossFitter if they’ve met “Pukey the Clown” and they’ll probably tell you yes. Due to the nature of competition, the motivating atmosphere, and people’s desire to do well, many people in CrossFit often push themselves beyond their personal limitations (which can be a good thing)…but oftentimes they push themselves beyond that.
I totally get it. In my first CrossFit experience three years ago, I almost made myself puke because I wanted so badly to do well (even though I finished with a time that would make most regular CrossFitters probably laugh at me). Last year, I did another CrossFit workout that I hadn’t properly prepared for and cranked out 100 pull ups quickly…and I ended up walking around with T-rex arms for a WEEK because I physically could not straighten them. Not kidding.
3) In some extreme cases with a VERY small portion of CrossFitters, an incredibly serious medical condition called rhabdomyolysis can take place. When people push themselves too hard, too much, too fast, their muscle fiber break down and are released into the bloodstream, poisoning the kidneys. At CrossFit, they refer to this as “Uncle Rahbdo,” though it’s not something funny or enjoyable. You can read all about the condition and issues it can cause here. This typically occurs with (primarily male) ex-athletes who have not exercised for a while and come back trying to prove something and go at a higher intensity than their body can handle.
So…like with any activity, you can have people that like to push themselves too far, too hard, too fast, and too often. Unfortunately, due to the nature of CrossFit (where this behavior is encouraged and endorsed), you can end up in some serious danger if you don’t know when to stop or have a coach that will tell you when to stop.
Personally, I find these issues to be more with individual people than with the CrossFit system as a whole, but it is the nature of CrossFit that attracts these people and encourages them to behave dangerously. I’ll let you make your own decision here.