Traditionally speaking, athletes were on mainly their physical attributes in order to gain an advantage and improve performance. This can lead to ignoring mental health, stability and improving the mind. The brain has a very specific job and when it cannot do it's job to it's best ability neither can the rest of the human body. If you lose one arm, you're still considered alive, same for a leg and an eye, but when you lose the capacity to use your mind or brain, you can be considered dead even while breathing. This is should be a clear enough argument for your most important organ and it's importance. Let's look at some benefits of meditation.
Meditation actually helps to improve the usage of the brain, in fact according to www.askthescientist.com meditation has been shown to possibly thicken the-prefrontal cortex, which is the area of the brain responsible for decision making and focus.
According to PsychCentral meditation can strengthen memory, improve attention and focus. It can lower blood pressure, improve heart rate and eve assist and controlling and managing pain.