Each of us has missed workouts. There is nothing wrong in this. Intense load increases the stress level; that is why a good training program always involves a few days of rest. The only problem is that three days imperceptibly flow into six days, which are then prolonged to 10 days of workout escapism. At this time, there appears a reasonable question: how long does it take to lose the acquired physical shape?
Physical shape is lost in several ways, including muscle strength and heart endurance. The speed of the process depends on the duration of our rest and the level of physical fitness.
If you are a regular fitness goer
It is much easier to regain the original shape after a long break, if you have had regular workouts 4-6 times a week for a long time. For example, if you have been training several times a week throughout the year (you can be classified as an athlete), your muscle memory will allow you to quickly return to its former shape.
Loss of muscle strength
Much still depends on what caused the break. If a person is virtually without any movement (for instance, due to illness), muscle strength starts to get lost after 2 or 3 weeks. If a person leads an active lifestyle and maintains a light physical activity (even at the level of everyday situations), it will take 3-5 weeks before the person significantly loses strength.
For doubting people, we may add that these things are scientifically proven. Medicine & Science in Sports & Exercise journal has published several studies which involved track-and-field athletes, rowers and weightlifters as the object of study.
As a matter of fact, in all the three main groups of sportsmen, muscle fibers have not changed even after a month’s break in training. But at the same time, specialized muscles needed for a particular sport began to lose shape after two weeks of inactivity.
For example, the track-and-field athletes lost a significant amount of slow-twitch muscle fibers during the break. But the weightlifters lost some hard-won fast-twitch muscle fibers.
To sum up, it turns out that our body tries to maintain its overall muscle strength as long as it can. However, special skills required for specific exercises disappear much faster. We can say that the human body strives for universality.
Loss of endurance
Unfortunately, we are losing endurance noticeably faster than muscle strength. A study revealed that four-week abstinence from training results in a 20 percent reduction in the amount of oxygen that an athlete can absorb per unit of time (VO2 max).
There are other studies with similar results. For example, it was found that after 12 days of rest VO2max decreases by 7%, whereas the concentration of enzymes in the blood that are responsible for the endurance level is reduced by 50%.
It is worth mentioning that although endurance is lost much faster than muscle strength, it is easier to recover.
If you have just started to train
If you have just started to exercise, try to avoid prolonged rest. You do not have the habit of exercising, so your brain will look for any reason to skip workouts. As soon as you yield to this temptation, it will be difficult to bring yourself back on track.
Loss of muscle strength
It is interesting to know that beginners find it much easier to maintain physical strength after longer breaks than those who have been engaged in them for a long time.
A group of young men, who had not been engaged in anything before, were asked to make a three-week break in the middle of a 15-week training program. When the men completed the program (after the break), they had about the same level of muscle strength as those who did not have the break. Another study showed that the people, who had a four-month training program and a six-month period of rest, managed to keep 50% of the acquired muscle strength after that.
Beginners quickly lose concentric strength (when the muscles contract, overcoming resistance, such as while lifting barbells), but they lose eccentric strength slower (it occurs while resisting an external force, such as holding a barbell with the biceps effort).
Observing the 13 guys who had just started training showed that they retained the eccentric strength for three months after completing a three-month training program, but they almost completely lost the dynamic (concentric) strength.
Loss of endurance
The cardiovascular system is more sensitive to prolonged breaks in training. One of the best studies on this topic found that the level of VO2max, acquired after two months of hard training, had been completely lost after just a four-week break.
In addition to the fitness level that determines how fast you regain the previous physical shape, there are other factors that also play a role.
Firstly, one should take into consideration a person’s age. If you compare the people who are 20-30 years old and those who are 65-72 years old, the older group will lose muscle strength twice faster.
Secondly, the reason why a person is having rest matters. Here are the results of an interesting study. The volunteers, who were not involved in sports, were injected hormones that led the person into a state of stress, such as that caused by an injury or illness. During the following 28 days, these people lost 28% of their muscle strength, which is much more than the average level.