Investigators found that diabetic men who were physically fit were less likely than their less-fit peers to die of any cause over about 15 years. What's more, men who were heavy yet fit had death risks similar to those of fit normal-weight men.

"This is a testament to the power of being physically active," said lead study author Dr. Timothy S. Church, medical director of the Cooper Institute in Dallas. "Essentially, fitness totally negated the effects of being overweight," he told Reuters Health.

Church and his colleagues report the findings in the January issue of the journal Diabetes Care.

The study involved nearly 2,200 men who were followed for an average of just under 15 years. All had undergone a range of health assessments, including treadmill tests to gauge their fitness levels, upon entry.

Church's team found that, with all health factors considered, greater fitness meant a lower risk of death over the years, regardless of weight. The biggest difference in risk was seen among obese men, where those who were only moderately fit had a much lower risk of death than those who were the most out of shape.

This is significant, according to Church, because it doesn't take a grueling exercise regimen to achieve such a level of fitness. Thirty minutes of walking five times a week should do it, he noted.

Excess weight and obesity are major factors in type 2 diabetes, and weight loss can often help control the disease and its complications, which include heart disease and stroke. The new findings do not minimize the importance of weight control in managing diabetes, according to Church and his colleagues.

However, Church said they do point to the power of physical fitness even in the absence of weight loss.

And, looking at the findings from a different perspective, thinness did not protect study participants from the ill effects of being out of shape. Among normal men, those who were the least fit were nearly seven times more likely to die than the most fit.

Doctors, Church said, should talk to all patients about getting and staying physically active.

Exactly why fitness cut death risk in this study is not fully clear, but better cardiovascular health almost certainly factored in, according to Church. However, the Cooper Institute researchers have also found that fitness is related to a lower risk of cancer death.

Source: Yahoo News: Reuters Health: Diabetes Care, January 2004.