Hi Clarissa. I believe in order to qualify to take the CSCS exam you must have a degree in some sort of medical field and/or an undergrad or grad degree in exercise science or a related field (like exercise physiology). I only know because I just finished a master's in Exercise Science and I'm looking forward to taking that exam. Of course if you don't have those degrees, you can always take their personal training exam (their certifications along with ACSM are considered to be among the best).
HTH
Carolyn