Heidelberg, Germany - In the third study to be published in as many weeks, German researchers are again extolling the virtues of physical activity for reducing the risk of coronary heart disease and stressing that it is never too late to start exercising [1].

Dr Dietrich Rothenbacher (University of Heidelberg, Germany) and colleagues report their findings from a small case-control study published online July 17, 2006 in Heart. Rothenbacher told heartwire that although there have been many studies on exercise and heart disease, this is unusual in that it examines the lifetime pattern of physical activity.

In an accompanying editorial [2], Dr S Goya Wannamethee (Royal Free and University College Medical School, London, UK) says the new study is timely because the subject of whether it is ever too late to start exercising "has been a key topic of research and discussion in recent years."

Rothenbacher et al assessed the physical activity patterns of 312 patients aged 40 to 68 years with stable, angiographically confirmed coronary heart disease and compared them with those of 479 controls—volunteers who were occasional blood donors and were matched with the patient group for age and sex.

Adulthood was divided into two life spans—early (20-39 years) and later (40-49 years for those aged under 50 at recruitment, and 50 years and older for the remainder). Around half of those with heart disease and seven out of 10 of the healthy volunteers said that they had been moderately or very physically active in younger and older adulthood. But around one in 10 of those with confirmed disease and around one in 20 of the healthy volunteers confessed to having enjoyed a lifetime of physical inactivity.

Compared with those who reported having been rarely or a little physically active in both life spans, participants who changed their exercise pattern to a somewhat or very active lifestyle cut their risk of CHD by more than 50%. When this category was broken up, it became evident that risk reduction was mainly driven by those who changed their physical activity from rare or a little before age 40 to very active in later adulthood—these subjects cut their CHD risk by 90%.

"We found a strong and inverse relationship between a more-intense physical activity pattern in adulthood and CHD morbidity," say the researchers.

"These results suggest that keeping up a physically active lifestyle in adulthood may be beneficial for preventing CHD in later life. Furthermore, these data provide evidence that changing from a sedentary to an active physical activity pattern, even if initiated at an older age, may result in a strong reduction of CHD risk."

Rothenbacher says doctors should stress to their patients that "they do not need to go to expensive gyms or do anything fancy. It's a simple issue—if there are an escalator and stairs, just take the stairs. Just keep active."

In the editorial, Wannamethee highlights some of the study's limitations, such as recall bias, but concludes, "Nevertheless, the findings are consistent with other prospective studies showing that taking up physical activity in later life is beneficial."

Despite the widely acknowledged benefits of physical activity, the majority of people take little or no exercise, she notes. Only about a third of men and a fifth of women in England manage the recommended 30 minutes of moderate physical activity on most days of the week, and figures are similar for the US. And these proportions fall to just 17% and 12%, respectively among those aged 65 and above, she says.

Given that physical activity also reduces the risk of diabetes and stroke and may prevent or reverse disability, it should be positively encouraged, she concludes.