You know how exercise increases the formation of new cells, crucial for learning and remembering? Well, an experiment suggests that exercise can make new cells that carry newly-acquired knowledge overwhelm old ones, hence affecting long-term memory, writes Gretchen Reynolds for NYT’s blog. That experiment, however, was conducted on mice. But another experiment on rats showed an unaffected long-term memory after exercising. Maybe certain types of long-term memory are affected by the birth of new cells after exercise than others, says Ashok Shetty, professor of molecular and cellular medicine at Texas A&M University. “But for now, he believes that the available evidence suggests that, unless you are a mouse, working out is going to be “quite beneficial” for your brain,” writes Reynolds.