According to exercise guidelines, you should get at least 150 minutes of exercise per week — and running is generally considered one of the healthiest ways to achieve that. However, there is evidence that excessive running can cause damage to the heart. In a few extreme cases, runners have died of heart attacks during events.
One study found that people who jog live longer than people who run at high speeds, while some studies have even found that excessive running is just as bad as no exercise at all.
So what gives? How much running is too much, and how hard is too hard? Let’s look at what the research has to say.
The Dangers of Excessive Running
First things first: yes, it is possible to run too much. It’s just a question of how much running that takes. Too much exercise can lead to overtraining — a state of chronic stress and fatigue that occurs when you overtax your body, exceeding its ability to recover from strenuous exercise.
When you become overtrained, you stop making progress. Your strength goes down, your mile time goes up. You get slower, weaker, tired. Your mood worsens, and you get sick more often.
Despite the name, overtraining is not purely caused by training too much, or too hard.
Rather, overtraining results from a combination of many factors: too much training, too much life stress, lack of sleep, under-eating, illness and nutrient deficiencies.
It also depends on training status — the more experienced you are at running, the more of it your body can take. Novice runners might only run 10 miles in a week, spread over several days. Elite runners, on the other hand, will typically run twice a day when preparing for a race — between 100 and 130 miles per week. And that’s in addition to cross-training activities such as swimming and weightlifting.
Do Runners Live Longer?
That still leaves the question of how running affects your lifespan. Will excessive running cause you to die young?
It is true that too much running can be bad for your heart (some research suggests that regular marathon running increases the risks of an abnormal heartbeat, damage to heart tissue and hardening of the arteries), and even runners can still develop heart disease. Runners occasionally even suffer heart attacks during races, but this is extremely rare, happening only a few times a year worldwide.
The Latest Research on Excessive Running
But the studies that call into question the healthiness of running all have one major flaw: they’re purely correlational, and can’t demonstrate causation. It may well be that many people who run a lot are doing so precisely because they’re unhealthy or overweight to begin with and trying to get healthier.
The fact remains that the overwhelming majority of studies have found that running is associated with a longer lifespan.
Even elite runners, who run over 100 miles most weeks, consistently live longer than average — however, they may not live longer than people who only run recreationally.
But while cardiologists involved in the studies say that competitive runners shouldn’t curtail their running, they do say there’s no need for moderate runners to extend their jogs in the hopes it will improve heart health.
“It appears that most people can get maximum health benefits with relatively low amounts of exercise, and that’s comforting,” exercise researcher Dr. Carl Lavie, medical director of Cardiac Rehabilitation and Prevention at the John Ochsner Heart and Vascular Institute in New Orleans, told the Boston Globe. “You don’t need to push it longer and harder if you’re trying to make yourself as healthy as you can be.”
Running is also associated with greater health benefits than resistance training, i.e. weightlifting. However, since resistance training has its own unique benefits, like increased bone density, the healthiest course of action is to combine both — lift weights a few days a week, and run or jog a few miles several times per week.
How to Avoid Dangers of Running
Running doesn’t need to be avoided, but moderation is key.
Let yourself have at least one rest day a week when you don’t run, and don’t force yourself to keep going past the point of exhaustion.
If you start to feel fatigued, sore and in a bad mood for several days in a row, or if you find that your progress stops or even reverses, you may be overtraining. In that case, the best thing to do is take two or three days off. If you find the extra time off improves your running, that’s a sure sign that you need to take things a little easier.
Remember, also, that not training too much is only half the solution — the other half is sleeping eight hours a night, minimizing stress and eating plenty of healthy food.
Ultimately, it’s about listening to your body — you should be running, but more isn’t always better.