It turns out turning 40 years old is a big deal because it means the part of your brain that is in charge of motion starts to decline.

What does it mean? Well, it means you will start to throw a ball slower, run slower and it can also affect how you swerve a steering wheel. This all comes from new research from the University of California, Los Angeles. Researchers say that by middle age, even if you are healthy, people lose some of the insulation in the motor-control part of the brain.

So, study author Dr. George Bartzokis says the discovery shows why "it's hard to be a world-class athlete after 40."

But, maybe there is hope. A completely different study finds eating blueberries can help improve brain function. Who knows if the magic fruit can help with motor-control skills... The full story on blueberries can be found here.