MUNICH, Germany (Reuters) - Good news for Bridget Jones and the millions who share the fictional diarist's angst and guilt for failing to jog their way to health and happiness.

A German scientist is now prescribing aimless sloth as the antidote to professional stress and the secret to a long life.

``People who would rather laze in a hammock instead of running a marathon or who take a midday nap instead of playing squash have a better chance of living into old age,'' Professor Peter Axt, co-author of the newly published study ``On the Joy of Laziness'' (Vom Glueck der Faulheit), said on Wednesday.

Axt, who teaches at a college in Fulda, emphasized that moderate exercise like walking -- at least if taken at leisure and not snatched hectically from the working day -- and avoiding overeating were nonetheless healthy. But overdoing it was not.

``Research shows that people who run long distances into their 50s are using up energy they need for other purposes,'' said Axt, a health researcher whose previous publications include ``Just Stay Young'' and ``Eat Yourself Slim.''

``They suffer memory loss. They risk premature senility.''

Committing heresy in a country where many consider waking after sun-up a sin, he also slammed early rising -- getting up too soon leaves people stressed for the whole the day, he said.

And keeping down stress was vital to good health, especially at work, added Axt, who writes with his physician daughter.

His prescription?

``Waste half your free time. Just enjoy lazing around.''