• According to research, taking a couple weeks off from running may decrease your heart and lung power.
  • However, to ensure your time off from running doesn’t turn into complete deconditioning, make sure you cross-train.
  • Depending on your injury or reason for not running, most likely some kind of non-impact exercise will work, from swimming and biking to yoga and even housework.

Between school, work, or family obligations, life can sometimes get in the way of our training without us even realizing it. Other times, you may want to step away from logging your miles because you feel an injury coming on and don’t want it to develop into something more serious.

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We can probably all relate to these scenarios in one way or another. But just how much of a difference does it make if you take a couple weeks off from running? Potentially quite a bit, suggests a new study in the European Journal of Sport Science.

Researchers looked at the effects of two weeks of detraining on heart and lung function and muscular fitness in 15 endurance-trained male athletes between the ages of 19 and 26.

They found that the weeks off resulted in a significant decrease in VO2 max (the measurement of the maximum oxygen delivery and utilization for cardiovascular exercise), exercise time to exhaustion, knee extensor strength, as well as maximal stroke volume (the max volume of blood pumped from the left ventricle of the heart per beat). However, they didn’t lose knee flexor strength or muscle endurance, and they seemed to maintain their lean muscle mass, researchers concluded.

One caveat to keep in mind is that this was a small study that used a similar sample group as well—only well-trained young men.

In terms of real-world applicability—if you take some time away from running, you’re likely to see some detraining effects but, fortunately, they probably won’t be so dramatic, according to Carol Mack, D.P.T., C.S.C.S., even if you’re sidelined because of injury.

“Two weeks in the grand scheme of things will not make or break your overall health,” she told Runner’s World. “It’s still possible to reach your goals even if you were training for a race and have to take a week or two off.”

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The trick in ensuring your time off from running doesn’t turn into deconditioning is by cross-training, she added. Unless you’re on strict bedrest, there is almost always an activity you can do to incorporate a little fitness into each day. Depending on your injury or reason for not running, you can engage in some kind of non-impact exercise, such as swimming, biking, yoga, and even housework.

“If your break is due to a non-injury cause, like a busy work schedule or bad weather, it’s important to find some way to get your heart rate up on the days you would have been running, even if it’s only for 15 minutes,” Mack said.


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Also important to note is that you need to come back into training gradually after those couple weeks off. Mack noted that reconditioning will depend on a few factors, such as the amount of fitness someone had prior to their break, the length of time of the break, and if they were able to do any cross-training in the meantime.

“After a two-week break, reconditioning would take around a week, but this could be longer or shorter depending on these factors,” she said.

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Elizabeth Millard

Elizabeth Millard is a freelance writer focusing on health, wellness, fitness, and food.