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If the Sunday Times crossword gives you a severe inferiority complex (or panic attack), try giving it the old college try after a 20-minute jog. Aerobic exercise does a body good, but ongoing research suggests that it's a boon for the mind as well, reports The New York Times.

It's been 10 years since the Salk Institute in California found that exercise stimulates the production of new brain cells, but the real questions are: What kind of exercise should we be doing and how much and how hard do we have to go?

According to a preliminary study published in the American College of Sports Medicine, aerobic exercise has a larger impact on reaction time, accuracy and memory compared to resistance training. In fact, resistance training seems to have no effect on cognition at all.

In the study, 21 students from the University of Illinois completed a memorization task before, immediately after and then 30 minutes after either sitting quietly, running on a treadmill or lifting weights. Researchers found that students' responses were more accurate and markedly quicker post-run.

"It's now been shown a dozen times that [aerobic exercise is] good for cognitive health and function," says Charles H. Hillman, co-author of the study and associate professor of kinesiology at the University of Illinois at Urbana-Champaign. The new piece of the puzzle, however, was strength training. "The mechanisms underlying these two types of [exercise] obviously differ as far as memory," he says, but is quick to note that strength training shouldn't be written off.

"There are a lot of benefits to strength training. [It improves] muscle strength, bone density, body composition and plays a part in the ability to perform aerobic exercise," Hillman says.

So how much aerobic exercise do you need to do before tackling that behemoth of a crossword? Hillman notes another study he co-authored in the journal Neuroscience, which found that only 20 minutes of walking at a moderate level (about 60 percent of maximum capacity) on a treadmill helped kids ages 9 to 10 perform better on academic achievement tests.

"You don't have to get out and run full-blown," says Hillman. A moderately-intense walk can provide you with a brain boost. And hey, it may be enough to give even the Sunday crossword a run for its money.

If you're not a running fan, That's Fit has plenty of aerobic alternatives to try. Leg warmers, Richard Simmons and leotards, oh my! Retro aerobics class, anyone?