Do you ever wonder what happens to your body after not exercising for 4 weeks?
Have you ever missed a day of training? How about a week of training? How about 4-weeks? If you have ever missed more than a week of exercise, this blog is for you. There are several changes that occur to the body when we don’t exercise. If you haven’t exercised in a while, we often think about how much weight we gained but is that really the big problem? Here are 5 biological changes that occur if you stop exercising.
Goodbye Muscle
According to a 2013 study, muscle loss in trained athletes can occur between 2-4 weeks. Now for those individuals who have not trained consistently for years, muscle loss can occur after 1-week of not training. The reason why retaining muscle is important is because it helps regulate your metabolism, it maintains glucose homeostasis, and even has its hand in immune system signaling. So without muscle, you limit your bodies ability to burn fat, you decrease your insulin sensitivity (trend towards pre-diabetes), and tend to get sick more often.
Reduced VO2 Max
The maximum amount of oxygen your body can use is one of the biggest variables that we see change with regular exercise. Unfortunately, it can also be something that can decrease quickly when we stop moving. A reduction in VO2 max results in a decrease in endurance and limits recovery. You know, like when you are taking the stairs and feel gassed out? Research has found that there is a 10% reduction in VO2 max within the first 4-weeks of when you stop exercising.
Reduced mobility
The body is always in a constant state of flux and adapts to the tension (or lack thereof) that is placed upon it. For example, if you sit most of the day, the glutes and low back will become strained. This will cause the muscles that surround your spine to tighten up to stabilize the back. Shoulders will start to round forward and the head and neck will start to take on more weight than it can handle. Loss of mobility can be seen and felt within 2 weeks. Range of motion and control of our joints decrease the longer we go without movement. The reason is the body will become stiff due to lack of neurological signaling. Less signaling means less blood flow. Less blood flow can lock up tissues and joints.
Mitochondria
Mitochondria is the power house of your cells. Mitochondrial function is important because it must produce energy (ATP) every second of the day as it cannot be stored. This function is so important that mitochondria can take up as much as 25% of a cells volume. Interestingly enough, because the brain uses 70% of the ATP, there is a strong correlation with mitochondrial dysfunction and neurodegeneration.
Now mitochondria can become down-regulated if, you guessed it, we don’t ask it to produce energy. Meaning, mitochondria can actually shrink and produce less ATP when we stop exercising. This begins to occur in less than a week of little movement.
Strength
Did you know that you can start to lose muscle strength within 48 hours? Skeletal muscle is highly adaptable and can respond to tension placed upon them. While strength can start to decrease within 48 hours, much of the longterm loss won’t fully occur until about 10 weeks of not exercising. So there is still time to get back on track even after you missed a few weeks. Just don’t expect to be 100%!
Although we suggest trying to avoid long breaks in activity, we know that this can be unavoidable. Life happens and we get sick, we get behind at work, or the kids need help in school. All of this can impact your overall fitness and health. However, if you find yourself it this situation, don’t freak out! Although our bodies start to slow down after a few weeks, it can rebound fairly quickly once you get back on track! Consistency is key and reducing the amount of missed days will help restore all of what you lost. Most people need 3-4 days of training per week but don’t neglect anything less than that. Even one day a week of training will help get the ball rolling again!