Washington: Brisk walking for just 30 minutes daily is enough to half the risk of premature death of men from all causes, according to new research.

The US-government-sponsored analysis — the largest such study ever — found that a regimen of brisk walking 30 minutes a day at least four to six days a week was enough to halve the risk of premature death from all causes.

“As you increase your ability to exercise — increase your fitness — you are decreasing in a step-wise fashion the risk of death,” said study author Peter Kokkinos, director of the exercise testing and research lab in the cardiology department of the Veterans Affairs Medical Center in Washington, D.C.

That conclusion applies more or less equally to white and black men, regardless of their prior history of cardiovascular disease. According to Kokkinos, that may be because the veterans in the study all received the same level of care, regardless of income.

This evened the playing field, he said, giving him “great confidence” in the results, which will be published in the Feb. 5 issue ofCirculationand were released online Jan. 22.

In the study, Kokkinos and his team reviewed information gathered by the VA from 15,660 black and white male patients treated either in Palo Alto, Calif., or in Washington, D.C.

The men ranged in age from 47 to 71 and had been referred to a VA medical facility for a clinically prescribed treadmill exercise test sometime between 1983 and 2006. All participants were asked to run until fatigued, at which point the researchers recorded the total amount of energy expended and oxygen consumed.

By tracking fatalities through June 2007, Kokkinos and his colleagues found that for both black and white men it was their fitness level, rather than their age, blood pressure or body-mass index, that was most strongly linked to their future risk for death.

The study proved that it takes relatively little exercise to achieve health benefits.