Rhabdomyolysis, or rhabdo for short ... and group settings, like CrossFit, spin classes, or Navy SEAL training. “With the group mentality, there's a lot of peer pressure to exercise harder ...

Rhabdo is also more common in people with sickle cell trait, a genetic blood disorder. Doctors and researchers point to the popularity of intense workouts like HIIT or CrossFit, year-round sports ...