The effects of statins on exercise benefits.
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The effects of statins on exercise benefits.

Doctors say statins, the most widely prescribed type of cholesterol-lowering drugs, have prevented millions of heart attacks and saved countless lives. But a new study published in the 'Journal of the American College of Cardiology' found that these meds, including Lipitor, may also counteract the benefits of exercise, the other tried-and-true way to boost cardiac health.

Researchers started a small group of overweight, sedentary adults at risk of developing high cholesterol or blood pressure on a 12-week aerobic program. They also put half of the patients on simvastatin, sold commercially as Zocor. By the study's end, the exercise-only group's VO2 Max, a measure of aerobic fitness, had increased 10 percent, while the group also taking simvastatin had only seen a 1.5 percent improvement. The statin users' muscle function also decreased 4.5 percent while the first group's shot up 13 percent.

"Our research suggests that statins block exercise's ability to increase mitochondria, which are the powerhouses of the cell and where oxygen is consumed and converted to energy so that muscles can contract," explains senior study author John Thyfault, professor of nutrition and exercise physiology at the University of Missouri. "Typically, exercise increases mitochondrial content in muscle, which allows for improved fitness."

And improving fitness is clutch, says Thyfault. "For disease and mortality risk, the literature is increasingly clear that fitness is the most important measure, not cholesterol or other single risk factors," he says.

If that's the case, then these findings seem to create a conundrum. Should someone on statins not bother exercising? Should a person with disease risk factors or a family history of health ailments skip the statins and hit the treadmill instead?

According to Thyfault, the answers aren't cut and dry. Statins may have blunted the patients' mitochondrial production and aerobic capacity, but that doesn't mean they blackballed all benefits of exercise. The group experiencing decreased aerobic rewards for their workouts was still burning calories.

"I would not take these results to mean that everyone should stop exercising if taking statins," says Dr. Christine Lawless, co-chair of the American College of Cardiology's Council on Sports and Exercise Cardiology. "Just because statins hindered mitochondria production, we can't say exercise's benefits were totally negated. The positive effects on the heart and longevity could still be there, as well as how much better people can feel after exercising."

Lawless points out that this research focused on just a small group of people and that the medical community considers statins to be extraordinarily safe. Lawless actually believes statins are under-prescribed, given the amount of evidence showing they're helpful.

Still, Thyfault feels people shouldn't be overly eager to take statins like Torvast, Crestor, and Lipostat: "I would suggest that people be cautious if their cholesterol is not high or even borderline."