Miami ? Olga Leon could be the poster child for a decade-long nationwide study on pre-diabetic patients. At 74, she pumps iron at Don Shula’s Athletic Club in Miami Lakes, Fla.

She strides the treadmill, lifts weights, does aerobics and Pilates.

She eats six eggs for breakfast — whites only, of course — and drinks a shake of cucumbers and water. Ten years ago, Leon was overweight and pre-diabetic with a system that was developing glucose intolerance. Her luckiest day, she says, was when she got into a national study, run in part by the University of Miami, to see if strict diet and exercise could keep her and more than 3,000 subjects like her from getting full diabetes.

It worked.

Today, Leon, weighs in at 133 pounds, 35 pounds lighter than when she started, has great cholesterol numbers and not one trace of diabetes.

The national study — which appears online today in the peer-reviewed journal, The Lancet — concluded people who stuck to the prescribed diet and exercise for 10 years cut their diabetes risk by 34 percent.