CAT | Studies
Every year about 720,000 Americans have a heart attack; for more than 200,000 of them, it’s not their first.i Heart disease is still the number one killer in the United States, but we are making strides toward improving nationwide heart health by increasing awareness about healthy lifestyle choices such as eating well and staying active. When it comes to exercise, however, a new study found that overdoing it may have the opposite effect.
Researchers at the Lawrence Berkeley National Laboratory in California recently completed a decade-long study in which they analyzed the effects of increased physical activity on nearly 2,400 heart attack survivors. While increased exercise was shown to reduce the risk of dying from a heart attack by up to 65 percent, excessive exercise—running more than 30 miles a week or walking beyond 46 miles weekly—more than doubled the risk of having another attack.
Although only a small portion of the study participants were excessive exercisers (6%), study author and staff scientist Paul Williams cautions against overdoing it when it comes to physical activity post-heart attack. “More isn’t always better,” said Williams, recommending heart attack survivors stick to the Physical Activity Guidelines for Americans developed by the U.S. Department of Health and Human Services: 150 minutes of moderate-intensity exercise or 75 minutes of vigorous-intensity exercise weekly.
A new report from the Environmental Protection Agency brings good news for public health. According to the EPA, in just over two decades the organization has taken great strides toward its goal of significantly reducing toxic air pollution as required under the 1990 updates to the Clean Air Act.
Even as the economy has grown, there has been a reduction in the emissions of six common pollutants (including benzene, mercury and lead) by an average of 72 percent nationwide—and Americans today breathe less pollution and face lower risks of premature death and other serious health effects.i Environmental damage from air pollution is also significantly lower; many plants and factories are cleaner; and countless new vehicles feature improved emission control technologies. (The EPA also hopes to reduce motor vehicle air toxin emissions by 80 percent by the year 2030.)
“It shows that we’ve made considerable gains in improving air quality across the country,” said EPA Administrator Gina McCarthy in a recent article, though the organization says there is still much more work to be done. Among the major challenges are limiting climate change, reducing health and environmental risks from toxic air pollutants, and protecting the fragile ozone layer against degradation.
In working toward improving air quality and public health, the EPA says it also plans to increase public awareness about air pollution—in part by requiring companies that produce large amounts of emissions to report to EPA officials, who will then make sure the public has access to the information.