It's worth considering prescribing physical activity just as drugs are prescribed, a journal commentary says. (Ben Stansall/AFP/Getty)

Doctors should emphasize the value of physical activity for lowering cholesterol, say researchers who studied how well exercise works compared to standard drug treatments.

Researchers in Washington, D.C., checked the medical records of 10,043 veterans in the U.S. with high levels of harmful cholesterol.

Mortality risk was 18.5 per cent in people taking statins compared with 27.7 per cent in those not taking the medications, Peter Kokkinos from the Veterans Affairs Medical Center and his co-authors concluded in this week’s issue of The Lancet.

The researchers looked at the subjects' aerobic exercise capacity using a treadmill test in units called METs, where one MET is the energy expended at rest. The U.S. Centers for Disease Control and Prevention lists walking for pleasure as moderate intensity of 3.0 to 6.0 MET.

For each 1.0 MET increase in exercise capacity, the mortality rate fell by 17 per cent for those taking statins compared with 11 per cent in those not taking the medications, the researchers said.

Combining treatment with statins and an exercise capacity of more than 5.0 MET, such as playing competitive sports, lowers mortality risk substantially more than either approach alone, they noted.

For patients who can't be prescribed statins, achieving a moderate fitness level of 7.1 to 9.0 MET "offers moderate protection against premature mortality,” the study’s authors concluded.

With greater exercise capacity, the protection is at least as much if not greater than for those in the moderate fitness range who took statins.

"Physical activity, which improves fitness, is an efficacious and cost-effective means to prevent premature mortality and therefore should be promoted by health-care providers."

Those taking statins tended to be older and had a higher body-mass index and lower exercise capacity than those not taking the drugs.

Pedro Hallal of the Federal University of Pelotas in Rio Grande do Sul in Brazil and I-Min Lee of Harvard Medical School in Boston called it striking that patients not prescribed statins but were highly fit had a lower risk of premature mortality than those taking statins but were unfit.

"If clear and equivalent health benefits can be achieved through being physically active or fit, prescription of physical activity should be placed on a par with drug prescription," they wrote in a journal commentary accompanying the study.

"We are not advocating against treatment with drugs of proven efficacy, but emphasizing the importance of another type of treatment, which is complementary, cheap, and has few side-effects when used according to the guidelines."

There was no funding for the study.