3 hours of exercise a week helps artery health

According to a recent article in the Journal of the American College of Cardiology, reported by ReutersHealth, as little as three hours per week of exercise helped overweight teens have better arterty health and greatly reduce a condition known to lead to hardened arteries later in life:
Green's team focused on flow-mediated dilation, which measures how well the endothelium, the lining of the blood vessel, acts to keep blood moving by widening the vessel. . . .

For 8 weeks, participants completed three 1-hour sessions of aerobic activity and weight training.

At the start of the study, obese adolescents had impaired endothelial function compared with their lean peers. But blood vessel function had improved significantly by the end of the exercise program. . . .

"We believe, on the basis of this and other studies we have performed, that exercise has a direct and beneficial effect on artery health, as well as the indirect but beneficial effect exercise possibly has through decreasing blood lipid levels, blood sugar and blood pressure," Green said.
Although the teens had better artery health and several other healthy developments, their overall weight did not change. "But they did experience healthy changes in their body composition, including increased muscle mass. They also experienced a decrease in fat around the abdomen. This type of fat is strongly associated with an increased risk of cardiovascular disease."

This is a strong indication that the value of exercise goes beyond simple weight reduction, and whether or not exercise leads to weight reduction, it is still valuable and leads to better health.