“…In the course of a long peace, the people relax into sloth and indolence…”-Manners of the Germanic Tribes by Cornelius Tacitus (end of 1st Century CE)
Perhaps the secret to health is recognizing the reciprocal duty and bonds between oneself and ones countrymen–and endeavoring to maintain the health reserves you could potentially need to pull your weight in an emergency.
Consider the lyrics of the Norwegian National Anthem:
“And, as warrior sires have made her
Wealth and fame increase,
At the call we too will aid her
Armed to guard her peace.”
–And the Norwegians take this seriously as evidenced by the popularity of the Biathlon. Here is a video that shows just how much of an athlete one must be to do well at this sport.