Next time you're looking to add someone to your team for a key project, you might want to consider a key attribute that might seem totally irrelevant at first:  physical fitness.

You may have heard in the past that science has shown exercise is good for the brain, but a new study takes it a bit further, finding that fitness is linked to superior brain structure and functioning in young adults. 

In other words, fit people's brains seem to actually work better than the less in shape. 

Maybe it's time to rethink that treadmill desk

The study used a database of over 1,200 brain scans and volunteers with an average age of 30 years old who performed some additional tests. To measure fitness, the volunteers were asked to walk fast for two minutes and were also given cognitive tests to gauge qualities including memory, sharpness, judgment, and reasoning.

Analysis of the results showed that the better walkers were associated with higher cognitive performance and with more healthy white matter on their brain scans, which is known to boost speed and quality of the brain's nerve connections. 

"It surprised us to see that even in a young population cognitive performance decreases as fitness levels drops," explained research team leader Dr. Jonathan Repple from the University Hospital in Muenster, Germany. "This leads us to believe that a basic level of fitness seems to be a preventable risk factor for brain health."

The hidden pro tip here is that, rather than measuring team members on their cognitive skills with complicated tests, perhaps you could just see who walks fastest to figure out who your top thinkers are. 

The new study, which is published in the journal Scientific Reports, also improved on previous similar work by controlling for possible hidden causes like body weight, blood chemistry, age and education status.

"The great strength of this work is the size of the database," Repple said. "Normally when you are dealing with MRI work, a sample of 30 is pretty good, but the existence of this large MRI database allowed us to eliminate possibly misleading factors, and strengthened the analysis considerably."

He adds that the connection between fitness and brain function leads to the obvious question of whether improving fitness directly leads to improvements in brain health.

"Finding this out is our next step. There are some trials which point in that direction, but if we can prove this using such a large database, this would be very significant."

Notify school teachers everywhere: "Thinking caps" should also come with running shoes.