Professor Peter Axt recommends avoiding strenuous activity like aerobics or working out in a gym.
People who prefer to 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.
says this scientist.
They are also less likely to suffer from professional stress.
He co-wrote On the Joy of Laziness with his daughter, who is also a doctor.
In the book he advises people to waste half your time.
Just enjoy lazing around.
Those who get up early in the morning usually feel stressed for the rest of the day,so his advice is to take it easy.
However, Professor Axt streses that liziness is only one of the keys to a longer life.
In fact, the subtitle of his book is How best to use your energies.
He argues that if you are too fat, you need more energy to maintain body functions, and is in favour of moderate exercise like meditative jogging or brisk walks to relax body and spirit at the same time.