Planning to run your first marathon (perhaps here in Minnesota) this year? It may help you turn back the clock on your aging cardiovascular system.
According to a new study, training for and completing a first marathon is associated with reductions in blood pressure and stiffness of the aortic artery (the large artery that carries blood away from the heart) that are significant enough to be equivalent to a four-year drop in age.
The greatest benefits were seen among older, slower, runners — particularly men — with higher blood pressure readings before they started training for the race.
And the training wasn’t particularly lengthy or onerous. None of the people in the study trained longer than six months, and during that period most ran only three times a week.
“Our study shows it is possible to reverse the consequences of aging on our blood vessels with real-world exercise in just six months,” said Dr. Charlotte Manisty, the study’s senior author and a cardiologist at University College London, in a released statement.
The study was published Monday in the Journal of the American College of Cardiology.
All novice marathoners
For the study, Manisty and her co-authors recruited 138 first-time marathon runners who had “won” a place in the 2016 or 2017 London Marathon through the event’s random ballot selection process, which occurs six months prior to the race. The participants were almost equally divided between men and women and ranged in age from 21 to 69, with an average age of 37. None had cardiovascular disease or a history of any other significant medical condition.
In addition, none of the participants was running more than two hours a week when they found out they were eligible to run the London Marathon.
The researchers took various health-related measurements of the participants at that time — before the participants started training for the marathon. Among the things measured were blood pressure and aortic stiffness (which was done by magnetic resonance imaging). The researchers then used the relationship between each participant’s age and the stiffness of their aorta to determine their “biological aortic age.”
As background information in the study points out, stiffening of the aorta and other arteries is associated with advancing age and is believed to be detrimental to health even in the absence of atherosclerosis (a buildup of plaque within the arteries). It’s been linked not only to cardiovascular diseases, such as heart disease and stroke, but also to kidney disease and dementia.
Blood-pressure-lowering drugs can help modify arterial stiffening, but — as the study also points out — heart attacks, strokes and other cardiovascular “events” are more likely to occur in people who have not been diagnosed with high blood pressure (and who are thus not taking medication for it) than in those who have.
That’s where regular aerobic exercise comes into the picture. Some studies have suggested that taking up aerobic exercise for even short periods of time can help improve both blood pressure and arterial stiffness.
Those studies involved people whose exercise was closely supervised, however. The current study was designed to observe what happens when individuals up their exercise levels on their own, in a “real-world” situation.
Although they could follow whatever training schedule they wanted, the study’s participants were given a “Beginner’s Training Plan” recommended by the organizers of the London Marathon. That plan’s schedule focuses on three runs a week, which increase in difficulty during the 17 weeks leading up to the marathon.
The schedule was sufficient to get the participants to the marathon’s finishing line — within 5.4 hours for the women and within 5.4 hours for the men, on average. Both of those completion times are about half an hour slower than average for the London Marathon, Manisty and her colleagues point out. Those times are also consistent with a training schedule of six to 13 miles a week, which is within the recommendations of the current U.S. physical activity guidelines.
One to three weeks after completing the marathon, the participants were brought back to the lab to have their health reassessed. The researchers waited at least a week to do the reassessments to make sure they weren’t just capturing the short-term effects of running the race.
The second round of data revealed that the participants’ systolic blood pressure had dropped by an average of 4 mmHg, and their diastolic pressure had fallen by an average of 3 mmHg — amounts comparable to what occurs when people take first-line medications to reduce high blood pressure, the researchers say.
The study also found that the distensibility of the participants’ aortic artery — the ability of the artery to be more elastic when blood pressure rises — increased by an average of 9 percent.
“These changes are equivalent to approximately a 4-year reduction in vascular age,” the researchers write.
The greatest cardiovascular improvements were found among the participants who began training with higher blood pressure than the others — most notably, the older, slower, male runners.
Interestingly, the study found no association between beneficial changes to the arteries and the participants’ weight or body fat. That finding suggests, say the researchers, that increased aerobic exercise has a direct impact on the structure of the vessels’ walls.
Adding to the evidence
This was an observational study, which means it can’t prove that aerobic exercise — specifically, running — leads to lower blood pressure and more flexible aortic arteries. Training for the marathon could have encouraged the study’s participants to adopt other healthy behaviors that led to the results.
In addition, the study involved only healthy adults. The findings may not apply to people with high blood pressure, whose arterial walls tend to be stiffer and perhaps less modifiable.
Still, this study is just the latest in a growing body of research showing how regular exercise can help slow down biological aging.
“Examining the consequences of first-time marathon training helps to understand the benefits from real-world exercise behavior that people enjoy and may continue if motivated and free from injury,” write Manisty and her colleagues. “A goal-orientated exercise training recommendation (“sign-up for a marathon” or “run a fun-run”) can be a good motivator to keep active and may increase the likelihood of sustaining benefits.”
“This study emphasizes the importance of lifestyle to modify the aging process,” they add, “particularly as it appears ‘never too late’ to gain the benefit.”
FMI: You’ll find an abstract of the study on the website for the Journal of the American College of Cardiology, but the full paper is behind a paywall.