Just a few minutes of exercise every day could help improve fitness and health of women who are inactive and overweight, US scientists say.

Conducting tests on overweight and obese women, many of whom had high blood pressure, researchers at Louisiana State University, Baton Rouge found that even ten minutes of exercise a day improved their fitness and toned them up enough to lower their overall risk of early death.

The study in the Journal of the American Medical Association is the first to reinforce with concrete medical data that exercise does not have to be an all-or-nothing venture, and lead researcher Timothy Church says the information should be used to encourage sedentary adults to find the time for some activity each week.

While everyone knows that exercise is good for you, 20 percent of US adults admit they do no exercise at all and most do not get as much as is recommended, reported health portal News Medical.

The US Centers for Disease Control and Prevention and National Institutes of Health recommend at least half an hour of moderate exercise to reduce the risk of heart disease, stroke and cancer.

The Institute of Medicine, which advises the US government, says people need to get themselves slightly out of breath for close to an hour every day.