IVAN HILTON SCIENCE BUILDING INFORMATION

 

photo of Dick Greene

Dick Greene

Chicago – Walking can increase the supply of blood to the brain, according to a New Mexico Highlands study presented at the American Physiological Society annual meeting at Experimental Biology 2017 in Chicago.

Highlands biology and physics professor Earnest Greene presented his findings in a poster session April 24 in Chicago.

“The dynamic effects of walking, running, and cycling – natural whole body movement as in work or physical exercise activities – on human brain blood flow were simply unknown,” Green said. “It was assumed that they were, as in rest, closely controlled and generally held constant.”

Greene and his team of Highlands undergraduate and graduate students worked with researchers from the University of New Mexico School of Medicine, the University of Colorado School of Medicine and the University of Copenhagen School of Medicine. The team used ultrasound to measure internal carotid artery blood velocity waves and arterial diameters to calculate blood flow to both sides of the brain of 12 healthy young adults during standing upright rest and steady walking. The researchers found that while there is lighter foot impact associated with walking compared with running, walking still produces larger pressure waves in the body that significantly increase blood flow to the brain. While the effects of walking on blood flow to the brain were less dramatic than those caused by running, they were greater than the effects seen during cycling, which involves no foot impact at all.

“Blood flow is not constant and varies significantly with various forms of exercise and movement,” Greene said. “As expected by simple hydraulics, the reversed and reflected pressure waveforms that are created by the foot impacts dramatically modify the central blood pressures that drive blood to the brain. The flow simply follows the pressure waveforms that are created by the interaction of the heart rate and stride rates.

“Some suggest this gives a ‘walker’s or runner’s high,’” said Greene, who is currently a Jefferson Fellow at the National Academies of Sciences, Engineering, and Medicine.

Greene, who earned his doctorate from Colorado State University – Fort Collins, is a native New Mexican and the first person in his ranching family to go to college. During the course of his career, Greene helped introduce echocardiography, the use of ultrasound waves to study the heart, in New Zealand and China and started the first bioengineering program at the University of Brazil, Rio de Janeiro. He served on the editorial board of the Journal of Ultrasound in Medicine, chaired several research and review committees, and has 100 published manuscripts in peer-reviewed journals and two published books.