By Martine Louis
Reporter Staff

A reformed smoker, a heart attack survivor and a former NFL linebacker; these are just a few members of team NOVA who are preparing for the 34th annual NOVA Marathon Challenge. The show, which airs Oct. 30 at 8 p.m. on PBS, allows viewers to watch 13 men and women&emdash;some athletic, some with no physical background, and some completely unhealthy&emdash;fight to achieve their dream of running the 26.2 miles to the finish line.

As the race approaches, viewers get to know team member and Dorchester resident, Dr. Xenia Johnson. A ballet, jazz and tap dancer since the age of five, Johnson says she has been sedentary for the last few years.

"I have always dreamed of running a marathon," said the 40-year old pediatric psychiatrist. "What especially drew me to this challenge was the science study and the benefit of watching how my life would change."

The "science study" is conducted by NOVA researchers, looking into the physiology of running and how the body adapts to the demands of long distance locomotion.

Unlike a number of her teammates, Xenia is relatively healthy, but her family has a history of hypertension and diabetes - something she says she never paid attention to until the marathon.

"I was not watching my diet or making healthy decisions, basically putting myself at risk of repeating family mistakes," said Johnson. "I wanted to do something about that. Avoiding illness was one of my biggest motivations."

Xenia, who moved from South Carolina nine years ago, said one of her challenges was to overcome her aversion to the winter season.

"Before NOVA, I had spent my winters hibernating, but this has been an experience about overcoming obstacles. Once I got over my fears I was able to broaden my Boston experience. I got to know my community and became more aware of its character and personality."

Johnson said she thought it was more about physical improvements at the beginning of their nine-month training process, but soon learned it was more of an emotional and mental journey.

"I have become a more goal orientated person and for that, training was great," said Johnson. "When I first started, my body was in very poor condition and I worried that any small thing would cause me a set back. My advice for those who feel they can't make it is to remember that there are no victories without obstacles. Obstacles are not final, they are part of the process of success."

From medical school to her residency, Johnson said this marathon has been the hardest thing she has ever done. She believes the best way a person can achieve their major goal is to break it down into smaller goals.

"I could never have completed 26 miles if I didn't first complete mile number one," said Johnson. "I was taking it grass blade by grass blade and that's the way you have to approach life&emdash;step by step."