Thirteen days later, Eagleton conceded what Democrats and journalists had been whispering about for days: that he had been hospitalized three times in the 1960s for depression and stress, and that he had undergone electric shock therapy.

NPR: The Eagleton Fiasco of 1972

That's caused by the adrenaline and stress hormones that the body releases in response to the shock of the cold temperature, but experts say that these rushes are not as healthy as people think.

CNN: Are polar bear plunges good for you?

All big banks today must receive approval from the Federal Reserve before increasing their dividend or stock buyback program, as well as pass regular stress tests that probe whether the financial institution could withstand a large shock.

FORBES: Move up http://i.forbesimg.com t Move down

Even if our basic theory is that economy is elastic in response to nominal stress and plastic in response to real stress, a sudden change in rigidity combined with a large nominal shock could cause a very large plastic deformation in the economy.

FORBES: NGDP in the Long Run and Economic Plasticity

Some pros and coaches say modern, deadened strings increase the stress on a player's arm if strung too tightly, bringing more shock through the strings, up the racket and into the body.

WSJ: Roger Federer: With Tennis Rackets, He Strings Them Loose