After two years of staying close to home you may have taken a vacation this summer. Maybe you had an active summer and maintained your fitness. More likely, you took relaxing on your vacation a bit too seriously and fell out of your normal exercise routine.
Athletes have long known that even a short break from training results in significant decreases in fitness and performance. You may have noticed this yourself after taking time off. Research shows that taking time off from exercise can also have a negative impact on your health.
Let’s explore how and why this happens, and what you can do to prevent it.
When you start an exercise program your body adapts in ways that improve your strength and endurance.
Your aerobic fitness and endurance are enhanced by both cardiac and muscle adaptations. Your heart actually gets larger and stronger to pump more blood to your muscles. Within the muscles there is an increase in the number of capillaries, the small blood vessels that deliver blood to the muscle, and mitochondria, the part of the cell that produces ATP, the energy used by your muscles. Together, these adaptations allow the muscle to produce more ATP without fatigue, allowing you to exercise a higher intensity for a longer time without fatigue.
If you do resistance training (and you should!), you get stronger and your muscles get bigger, called hypertrophy. Lifting weights causes microscopic damage in the muscle, which leads to inflammation and soreness. This sounds bad, but your muscles respond by rebuilding stronger, allowing you to generate more force and causing the muscle to grow in size.
These adaptations are also a major reason that exercise makes you healthier, too. Your blood pressure, blood glucose, and blood cholesterol are all improved because of how your heart, blood vessels, and muscles respond to exercise. Additionally, exercise results in changes to certain hormones and how your body stores and uses or stores glucose and fat. The end result is that exercise has far-reaching beneficial effects on your health that simply can’t be matched by any other intervention, including medications.
When you stop exercising for a period of time you start to lose these adaptations. This causes both your fitness and health to decline. And it happens quickly, in as little as two weeks!
Research shows that regularly active adults who suddenly limit their usual activity for two weeks experience significantly impaired blood glucose control, increased fat storage, and lower fitness. It is important to note that in both studies these changes do not fully return to baseline after resuming normal activity for an additional two weeks. This means that the benefits of exercise are lost quickly and took a longer time to return to normal.
This is also true for aerobic fitness and muscular strength. Research done on athletes who stop training, perhaps due to an injury, shows that fitness declines rapidly with the first two weeks. Worse, it can take many more weeks to regain those fitness losses. You may not be a competitive athlete, but the same principle applies to you when you take time off from exercise.
Make it your goal to maintain some level of activity, even when you are on vacation. Time off can mean doing less, but it doesn’t have to mean doing nothing. Even a little exercise can help you maintain your fitness, keep you healthy, and make it easier when you return to the gym.