Deborah B. Sternlight '98 has come a long way from her early childhood days when she would listen with fascination as her father read her journals and encyclopedia articles about how the human body works.

Through research for her biology senior thesis, the 21-year-old scholar and athlete unraveled a question that has remained unanswered for the last 17,000 years-what limits human running speed?

She has received close to a half-dozen messages and inquiries every day since her research was first publicized in late April. She answers some, and forwards others to her adviser Peter Weyand, a research associate in biology. The pace, she says, has been "just insane."

"When I return to my room, e-mail and my answering machine are the last things I get to these days," she says. "What this whole media frenzy has shown us is what incredibly wide interest exists in this particular question of what limits human running speed."

Like those of many novel scientific discoveries, the concepts and model behind Sternlight's research were rather simple.

In order to be able to break down the complex motion of running into its component parts, Sternlight used a treadmill with a force plate embedded under the tread. The signal from the force plate was sent to a computer to measure and study the different variables that influence running speed.

Her 33 subjects included star athletes from Northeastern University as well as novice runners. She also requested tapes of the 1996 Summer Olympics from NBC to obtain the same data on Olympic record-breakers.

Many scientists currently believe that top running speed in humans is limited by muscular power, but Sternlight's research indicates otherwise-her findings focus on mechanical factors such as force, contact time and swing time.

Her thesis readers believe that her results may revolutionize how scientists approach running and speed, she says.

"It isolates the variables we need to focus on and raises many questions on the use and importance of many different muscles in determining running speed," she says. Sternlight and her adviser are currently working on publishing these findings in a major scientific journal.

Although Sternlight says her research experience was very rewarding, she is just as excited about sharing her passion for science with others.

For the last four years she participated in Experimentors, a public service program dedicated to teaching Cambridge elementary and middle school students about science. The program carries unofficial but crucial mentoring responsibilities.

Sternlight says personal interactions with many of her students helped her understand the impact she could have on them.

"I realized that the most minimal effort on your part can often make the greatest difference in other people's lives," she says.

Sternlight's other passion, sports, has also captivated her energy and attention for much of her life. Sternlight played for the varsity volleyball team during her first year and rowed novice crew during her junior year.

"Sports are really a great way to push yourself not only to find your physical limit but also to work together with other people, to push yourself to reach new levels," she says, noting that her brother, a professional basketball player in Israel, has been an inspiration to her.

Although she hopes to combine her interests in science and sports in the future, Sternlight says she wants to focus on a career in science and incorporate her athletic interests through that.

Next year, Sternlight will work for a health care consulting firm in Cambridge, and she hopes to attend medical school a few years down the road. She eventually wants to focus on fields such as medical physiology, physical therapy and prosthetics.

Sternlight says Harvard was invaluable in helping her pursue her passions and combine her interests. During her first year she started out as a physics major, then she also joined the classics department for a semester before finally switching to biology.

"I was trying on many different hats," she says. "But biology really fulfilled a lot of my interests."