I am always shocked by what happens when I skip out on my workouts for even just a few days. Returning to my exercise routine after a long weekend is hard, let alone a week vacation. The first few days back at it are always harsh; the workout seems harder than ever to finish, and I’m left with tired and sore muscles afterwards.

This leads me always to question, how fast do you lose muscle? How quickly do you really lose the strength you have build up by exercising? And how long does it take to get it back? Results from a new study provide some pretty shocking answers.

Two weeks of an immobile muscle leads to significant muscle loss

A study from Denmark published in the Journal of Rehabilitation Medicine took seventeen men about 23 years old and fifteen men about 68 years old, and immobilized one of their legs for two weeks.

Afterwards, the men did six weeks of endurance retraining on a bicycle. The results showed that only two weeks of not using one leg led to about a 28% loss of muscle strength in the young men, and a 23% loss in the older men. Both young and old men also lost significant leg lean mass. The findings show that in even a short time of not using a muscle, you can lose a significant amount of your muscle strength and mass. [1]

And what’s worse? It takes even longer to regain that lost muscle. After the two-week immobilization period, the men worked out on a bike three to four times per week for six weeks. Even after six weeks, muscle strength did not recover to the level it was at before the immobilization. This means it took at least three times the amount of time to regain muscle strength than it did to lose it.[1]

The study also showed that the younger you are, the more muscle you lose in a short period of time. Additionally, the more muscle you have in the first place (and the more fit you are), the more muscle mass you will likely lose with inactivity.[1]

Don’t let yourself become inactive

While the study used the immobilization of one leg, which simulates what would happen with an injury, the results show us how important it is to use our muscles regularly, and to not let ourselves go through long periods of inactivity. The more days you go without using certain muscles, the more you’ll lose your strength.

So do your best to maintain a regular exercise program. While rest days are a must, and getting out to do something fun and changing your routine is also important, don’t let too many days go by without using your body. Not only will this help you to stay healthier, but it will also make your workouts easier in the long run too; you won’t have to play catch up rebuilding your muscle if you don’t let yourself lose it in the first place. For tips on how to make exercise a regular part of your routine, read more here. Go here for other strategies to help motivate yourself to exercise.

For help recovering after an intense workout, try out these Best Muscle Recovery Supplements.

Share your experience

Have you ever experienced a quick loss of muscle due to inactivity? How hard was it to regain it? Share your experience in the comments section below.

[1] J Rehabil Med. 2015 Apr 21. [Epub ahead of print]