fitness center in andover, diana kiesel, has tried it all. from running to free weights. >> my favorite workout, anything that involves my full body. if i can move my whole body i love it. reporter: she's intrigued by the idea that her genes could reveal which exercises truly work for her. so diana agreed to try out dnafit. the company says their genetic testing profiles help people understand how dna affects their response to exercise and nutrition. you start with this kit, you sign a consent form, take a saliva sample, pop the swab back in the packaging and s it isn't cheap. the basic fitness profile is around $190, plus shipping. >> it's how you use the information. reporter: dr. lee kaplan is the director of mass general hospital's weight center. he says these tests can be valuable, but it depends on how they are interpreted. >> if a genetic test convinces you not to exercise because you're not going to get as much value out of it as your neighbor, that would be a results in 10 business days, though diana's kit took more than a month to p