But as nutritional nabobs explore the inner recesses of such research, keep in mind the caveat that emanated from Brain Research in August 1997: the journal confessed "the molecular bases for how exercise affects the structure and function of the brain are largely unknown."

"These are small studies," says Bennington, Vermont, Memory Clinic neuropsychologist Paul Solomon, PhD, of the drips of data that connect exercise to brain activity. "They are scientific, but they don't meet clinical standards for outcome measures…. [Nonetheless] it's certainly possible that exercise improves cognitive function."

Let us begin as a for instance with the University of California (UC) at Irvine's Institute for Brain Aging and Dementia and their study of so-called brain-derived neurotrophic factor (BDNF). The alphabetical BDNF actually renders brain cells healthier and helps them fight off injury associated with hypoglycemia, head trauma, stroke - and other disturbances large and small.

"Exercise increases BDNF levels in the brain," says UC Irvine researcher Nicole Berchtold, PhD, "especially in the cortex and the hippocampus, two brain areas that are critical for learning and memory, and higher cognitive function."

"I can think of many mechanisms," says neurologist Dr. John Absher, "that could potentially account for improved cognitive performance as a result of exercise."

A Matter Of Motor Skills
One of the aforementioned "small studies" can be found in the December 1998 issue of the journal Perceptual and Motor Skills. Researchers took a close look at the impact of exercise on accuracy, attention spans, and response times among ten women and eight men. Women and men both showed better results after exercise, according to the researchers, "suggesting that exercise improved performance especially under conditions of focused attention."

As for the direct sports connection, research in the Journal of Sports Sciences published in October 1997 reported upon exercise and decision-making among soccer players, establishing that "performance during exercise was significantly better than at rest," and that "exercise induces not only an improvement in a simple task, like speed of visual search, but also an overall increase in speed of information processing."

Endurance athletes were also tested for "cognitive performance after strenuous physical exercise" in research published in 1996 in the journal Perceptual and Motor Skills. Fifteen such athletes, between the ages of 18 and 42, pumped a bicycle at 75 percent of their measured maximum: they were tested both before and after the workout, and the study found they improved in cognitive tasks across the board after exercise. The more complicated the task, the better the endurance athletes did after exercise.

Another study, in the Australian and New Zealand Journal of Public Health in 1997, looked at 186 older women over a 12-month period of group exercise: those who exercised "showed significant improvements in reaction time, strength, memory span, and measures of well-being" compared to those in a sedentary control group.

As for younger women, a 1997 study by the President's Council on Physical Fitness showed that athletic girls "do better academically, report higher standardized test scores, have lower drop-out rates, and are more likely to go on to college than their non-athletic counterparts."

"Exercise is generally good for people," says the psychologist Solomon. "If it's good for your brain, that's an added benefit."