completing a cross fit workout is impressive for anyone. for steph hammerman the feat is more than impressive. it once was inconceivable. i was born three months premature. i lost a lot of oxygen and a bunch of blood through that process. reporter: steph has cerebral palsy. that develops after trauma to the brain during or after birth. now, people with the condition are often unsteady on their feet. they have impaired motor function. muscle coordination problems. and all of this could make cross fit training dangerous. but for steph, it s just another obstacle to overcome. all of my other brothers and sisters are completely able-bodied. growing up in that world, there was no there was no other way to live. reporter: she was always active. the inevitable freshman 15 in college made her really want to get in shape. i found a gym. i walked in. i said i want to become stronger. i hear cross-fit is awesome. would i be able to do this? reporter: within an hour she was hitting t
together. so the signals have to go to the brain and come back, now, look at the electric cord, you have the wires, but there s an insulator around it. if there s any erosion in that, then we ve still got it the message has to go through the nerves and if there s any attack, by your immune system on something called mialin, the since lainsulator. there s tremor and coordination problems and visual problem. bowel issues and that s called ms, multiple sclerosis, an attack on your central nervous system, it s auto immune and no cure for it, see it in women between the ages after 20 and 40 and you can see the erosion. kelly: exactly. and so the message is not going to get through and a leak of the information that we need and that s what all the movement and coordination is out of whack.