A new study says older adults who are physically fit have better spatial memory than those who are less healthy.
Spatial memory is the part of memory responsible for recording information about one's environment and its spatial orientation.
For example, a person's spatial memory is required in order to navigate around a familiar city.
Hippocampus is a brain structure located inside the medial temporal lobe of the cerebral cortex, and plays a major role in short term memory and spatial navigation.
Researchers from the University of Illinois and the University of Pittsburgh have found that fitness increases hippocampus size and improves spatial memory in humans.
Hippocampus size in physically fit adults account for about 40 percent of their advantage in spatial memory.
Previous studies have shown that the hippocampus shrinks with age, a process that coincides with small but significant cognitive declines. However, the rate at which this occurs, however, differs among individuals.
In the new study, the researchers measured the cardiorespiratory fitness of 165 adults (109 of them female) between 59 and 81 years of age.
Then, with the help of magnetic resonance imaging, they conducted a volumetric analysis of the subjects' left and right hippocampi. The participants' spatial reasoning was also tested.
They found a significant association between an individual's fitness and his or her performance on certain spatial memory tests.
"The higher fit people have a bigger hippocampus, and the people that have more tissue in the hippocampus have a better spatial memory," said U. of I. psychology professor Art Kramer, who led the study with Pittsburgh psychology professor Kirk Erickson.
"Even ignoring the hippocampus data, we see there is this significant and substantial relationship between how fit you are and how good your memory is, or at least a certain kind of memory, a certain kind of memory that we need all the time," Kramer said.
This is really a clinically significant finding because it supports the notion that your lifestyle choices and behaviors may influence brain shrinkage in old age," Erickson said.
"Basically, if you stay fit, you retain key regions of your brain involved in learning and memory," he added.
The study appears in the journal Hippocampus.