A quote from America’s 3rd President:
A strong body makes the mind strong. As to the species of exercise, I advise the gun. While this gives a moderate exercise to the body, it gives boldness, enterprize, and independance to the mind. Games played with the ball and others of that nature, are too violent for the body and stamp no character on the mind. Let your gun therefore be the constant companion of your walks.
I’m assuming he was referring to soccer in the penultimate line.