Fitness in Teen Years May Guard Against This
Swedish study found link between aerobic fitness at 18 and lowered heart attack risk in middle age
National health registers provided information on heart attacks the men suffered later in life. Doctors used this medical data to track men for an average 34 years following their military physical exam.
The researchers found that men with the lowest aerobic fitness had a more than twofold increased risk of later heart attack compared with men who were most fit.
The study authors also looked into the joint effect of obesity and fitness, and found that across all weight groups the risk of a later heart attack increased significantly when comparing the least fit with the most fit.
However, the fittest obese men ran a 71 percent increased risk of heart attack when compared to men who were unfit but lean. They also had more than four times the heart attack risk faced by the fittest lean men.
"This study helps to address the 'fitness versus fatness' question by indicating that both are important, but they are independently important," Daniels said. "Good fitness can't completely counterbalance the health effects of excess weight. Obviously, the best is to be normal weight and fit, which is what we should be aiming at for the majority of our population."
Muscle strength, which also was tested during induction, did not appear to provide the same heart health benefits as aerobic fitness.
Genetics likely plays a large part in the aerobic fitness of teens and, by extension, their protection against heart attack, Nordstrom said. Another study that focused on twins within this same set of patients found that 78 percent of the variation in their aerobic fitness could be chalked up to genetics.
But it could also be that men who are in good shape in their teens have adopted the sort of lifestyle that will keep them healthy later in life, said Dr. Mark Urman, a member of the American College of Cardiology's Prevention of Cardiovascular Disease Committee.
"If you're fit as a teenager, you're going to be more likely to stay in shape over the course of your life," Urman said. "The better shape you're in, the less apt you are to have cardiovascular problems."