Journal Articles


Exercises and points to increase the effectiveness of the 16-hour fast

Exercises and points to increase the effectiveness of the 16-hour fast

One of the easiest ways to rejuvenate on a daily basis is to fast for 16 hours and exercise. While either one alone is effective for rejuvenation, the combination of the two is even more effective. The combination is the key. So why is it important to combine the 16-hour fast with exercise for the most powerful effect? If you are going to challenge 16-hour fasting and exercise at the same time with the aim of rejuvenation, you want to do it based on scientific evidence and precautions, and extract the maximum effect efficiently. In this issue, Why is the combination of 16-hour fasting and exercise the most powerful? What kind of exercise is recommended during the 16-hour fast? What are the key points and cautions to maximize the rejuvenation effect? I have summarized these three points.


1. Why is the combination of 16-hour fasting x exercise so effective?

Three key factors that make the combination of 16-hour fasting and exercise effective

These are the three main reasons why 16-hour fasting x exercise is so effective in rejuvenating the body!

1) Because it accelerates cell cleaning and recycling and improves metabolism.
2) Because it makes it easier to maintain muscle and lose fat.
3) Because it breaks down waste in the brain and improves cognitive function.

Let us now discuss these three in detail.

2. 16-hour fasting x exercise accelerates cellular cleaning and recycling! Metabolism is increased!

Originally, one of the effects of the 16-hour fast was to promote cellular cleaning and recycling. In addition to this, by incorporating exercise, the effect is accelerated. As a result, it also leads to an increase in metabolism. So, how does it work? Let us unravel the reasons.

2-1. Autophagy is more active when combined with exercise

Autophagy is a cleaning process that cleanses the cells of bad proteins and pathogens that are harmful to the body. Through this action, cells are recycled and renewed while being cleaned from the inside out.

16 hours fasting x exercise activates more autophagy

Autophagy, which is activated by cell starvation, has actually been shown to be even more active when exercised at the same time.
Although autophagy is an action that occurs in cells throughout the body, it has recently been found to be more active in muscle cells, especially those that are exercised. Depending on the nature and duration of the exercise, exercise stimulates cellular metabolism by breaking down muscle cells. This makes sense, then, that with autophagy already activated by fasting, the addition of exercise would make autophagy more active.

2-2. Adding exercise makes it easier to maintain muscle and lose fat.

It is important and essential to keep the cells hungry for long periods of time to rejuvenate them, and unfortunately, the 16-hour fasting increases energy expenditure from the body's natural fat by not feeding the cells and triggers autophagy, which also causes cellular recycling to occur, Unfortunately, muscles are also more susceptible than ever to degradation due to starvation during the 16-hour fast.
The greater the stimulus and damage from exercise, the more muscle is broken down, but at the same time, the body's recovery process is equally active in terms of synthesis.
In other words, "moderate exercise with little damage" during the 16-hour fast, a perfect time for muscle breakdown, is effective for muscle maintenance because it activates not only muscle breakdown, but also muscle synthesis.

16-hour fasting x exercise to keep muscles in place and fat loss easier.

2-3. Removing debris from the brain & improving cognitive function by adding exercise

When you hear the words "blood glucose" and "insulin," you may have a strong image that they are related to obesity, but in fact, they are also greatly related to cognitive function.

16 hours of fasting x exercise to remove debris from the brain & improve cognitive function

Insulin not only lowers blood glucose levels, but also serves as a "brain cleaner" to remove debris from the brain.
This is most clearly demonstrated by the fact that complications of diabetes caused by poor insulin function include Alzheimer's disease and memory impairment. When insulin does not work properly, not only does blood sugar levels become high, but the brain becomes increasingly clogged with debris, which leads to brain dysfunction, dementia, and other problems. Therefore, since exercise is important to maintain both insulin and brain function, programs have been developed to prevent and improve dementia by stimulating the brain through aerobic exercise and games such as calculations.
Thus, it is recognized that exercise is effective in normalizing blood glucose levels and improving insulin function, and in fact, 16-hour fasting is one of the most effective ways to improve blood glucose levels.

In order to maximize the effects of the 16-hour fast, the preferred diet should be based on "Magowa Yasashi" (beans, sesame, wakame, vegetables, fish, shiitake mushrooms, and potatoes) and should be about eight portions of food.


Even if it is difficult to eat "Magowa Gentle" foods and you have to eat a heavy meal, if you can stop at the eighth portion, you can at least prevent excessive insulin secretion caused by too much carbohydrate intake.
If you can also incorporate exercise into your diet, you can improve insulin function and make it even better.

3. Aerobic exercise is recommended during the 16-hour fast.

Recommended exercise during the 16-hour fast is light aerobic exercise such as yoga, walking, light jogging or weight training.

Aerobic exercise is recommended for exercise during the 16-hour fast.

There are two major rejuvenation benefits of so-called aerobic exercise such as walking and jogging. One is the development of telomeres and the other is an increase in neural stem cells in the brain.
Telomeres shorten due to various factors such as aging and stress, but the longer the telomeres are, the longer the life span and the younger the apparent age.
The number of neural stem cells in the brain declines with age, resulting in increased forgetfulness and memory loss, but it has been shown that even exercise in adulthood can increase their number anew.

3-1. Simply taking a walk while having a pleasant conversation is effective enough.

Aerobic exercise is recommended to be combined with the 16-hour fast, but it has been shown to improve cognitive function more by moving the body while saying words, rather than just exercising silently.

Effective at an intensity that is enjoyable and conversational

Finding a family member or friend with whom you can enjoy talking and exercising together can also have a positive impact on your mental health. If you are going to go to the trouble, you may as well enjoy exercising, not only for its rejuvenating effects, but also for its mental enrichment.


HIIT stands for High Intensity Interval Training. HIIT may seem physically and mentally challenging for those who do not usually have the opportunity to be physically active.


However, HIIT is especially recommended for the Corona Disaster because it can be done indoors without the need to go to a gym or prepare training equipment, as long as it is done properly and in the correct way.
It also stimulates the sirtuin gene and stimulates the secretion of growth hormone, even though the workout takes less than 30 minutes at most.

Activation of the sirtuin gene further stimulates autophagy, which prevents the production of aged cells. In addition, secretion of growth hormone, also known as "rejuvenation hormone," helps various metabolism of the body, leading to the maintenance of a healthy body line and skin elasticity and luster.

Those who are confident in their physical strength, those who cannot spend long periods of time exercising but would like to work on it in their spare time, and those who want further rejuvenation effects are encouraged to give it a try.

4. Muscle training is not suitable during a 16-hour fast.

The exercise to be combined during the 16-hour fast is not just any physical activity.
Some may say, "Let's combine muscle training to make up for body contours," but that is not recommended.
If more muscles are destroyed by muscle training, it could activate autophagy and be effective in rejuvenating the body. You might think so, but we do not recommend combining a 16-hour fast with hard muscle training. The reason for this is the significant disadvantages when looking at the body's recovery.

4-1. It takes time for the body to recover during a 16-hour fast.

Autophagy, which provides various benefits, is triggered by fasting and calorie restriction, but strictly speaking, it is necessary to detect a lack of amino acids (protein). Therefore, when fasting for 16 hours, it is necessary to eat less protein such as meat and fish, and more plant foods such as vegetable salads and tofu.
Therefore, in addition to the quality of nutrients, the supply time is insufficient for muscles damaged by hard training to recover. During fasting, the muscles cannot be nourished for a long period of time, and there are concerns about prolonged muscle soreness and poor physical condition. By nature, training is for the purpose of building a healthier, stronger, and tougher body. However, hard muscle training during a 16-hour fast is likely to cause the results of training to be wasted due to lack of nutrition.

Hard muscle training during a 16-hour fast wastes the results of your training due to nutritional deficiencies.

When focusing on muscle synthesis, or recovery, rather than muscle breakdown, it is important to consume animal protein rich in essential amino acids and to avoid cell starvation due to hunger.
In other words, activation of autophagy and muscle synthesis/recovery are completely opposite processes, and it is impossible to seek the effects of both at the same time.
Even if you are a regular muscle trainer or an athlete who trains hard, if you want to challenge yourself by combining 16-hour fasting and exercise, try to do exercises that cause as little muscle damage as possible. One of the best options is HIIT, which I mentioned earlier, because it offers a variety of great benefits while causing little muscle damage.

5. 3 points to keep in mind when exercising during the 16-hour fast.


Exercise during the 16-hour fast is within the 8 hours available for eating!


The effects of hypoglycemia can be mild, with a strong feeling of hunger, or severe, with cold sweats, weakness to the point of immobility, and dizziness.
The 16-hour fast is a longer fast than that. It is not recommended to do strenuous exercise during the fasting period, when energy is easily depleted.
Exercise during the 16-hour fast should be done "within the 8-hour period when you can eat, and 2 hours after eating, when you have enough energy in your body.

5-2.[Meals] Pay attention to the amount of protein and sugar content.

Those who are bodybuilding and diet-conscious and are aware of their protein intake should be even more careful about overconsumption of protein and excessive restriction of carbohydrates.

Watch the amount of protein and sugar during the 16-hour fast.

Protein intake should be mainly vegetable-based and in palm-sized portions. Do not overeat.
While it is important to consume amino acids during training and to supplement your diet with plenty of animal protein such as meat and fish to help your body recover after exercise, it is best to refrain from doing so only during the 16-hour fast.
This is because too much protein and animal fat can make it difficult for cells to feel hunger and for autophagy to occur.
If you normally exercise and eat a high-protein diet, you may be concerned about protein deficiency, but remember that a "temporary nutritional deficiency" can have many rejuvenating effects. During the 16-hour fast only, try to eat less meat and fish and more plant-based foods.
If the activation of autophagy is your first priority, you will also benefit more from amino acids such as BCAAs and EAAs if you refrain from taking them only during the 16-hour fast.


Also, be careful about the amount of sugar in your diet.
In the past few years, many people may have adopted a "sugar restriction" policy, for example, cutting out white rice from their daily diet or eating only side dishes at night, in order to lose weight and improve their health. In fact, too much carbohydrate intake or excess carbohydrate that is not used in any situation can lead to the formation of an aging-causing substance called "AGE," which is bound to protein. Therefore, there is an opinion that "carbohydrate restriction is good for anti-aging.
However, if you fast for 16 hours and restrict carbohydrates at the same time, not only will you consume too much protein, but you may also run out of energy and suffer from severe hypoglycemia.
It is not recommended to fast for 16 hours and restrict carbohydrates at the same time.
Even if you eat late at night after a workout, do not skip white rice. The idea is to consume a good amount of carbohydrate, which is the body's energy depleter, but a moderate amount of protein, which is the body's building block, to promote cellular recycling.

Simultaneous challenge of 16-hour fasting and carbohydrate restriction is not legal.

However, eating such as shoveling down a large bowl of white rice in one sitting is problematic. Eating white rice all at once can cause a spike in blood glucose levels, resulting in a large amount of sugar that the body cannot use.
Considering the body's energy needs during the 16-hour fast, it is necessary to eat one bowl of rice three times a day. If you feel that one bowl of rice is not enough, you can add vegetables or soup to increase your satisfaction.

5-3. [16-hour fasting x duration of exercise] Ratio of 2:1 for the period of implementation and the period of rest.

In order to maintain a healthy body and mind and derive the rejuvenating effects of 16-hour fasting and exercise, it is best to have both a period of time to perform the program and a period of time to take a break, so that you can work on it without mental stress.

What is the duration of 16 hours fasting x exercise?

The best ratio between the period of implementation and the period of rest is 2:1, which is divided into a "reset/maintenance period" in which the body is "daringly destroyed and rebuilt" by 16-hour fasting and exercise, and a "period of body building with sufficient amounts of nutrition and rest. The "reset/maintenance period" is divided into "a period of building up the body by giving it sufficient nutrition and rest.
Specifically, the standard is 2 days of exercise followed by 1 day of rest, so it is recommended to do 4 days of exercise followed by 2 days of rest, or 2 weeks of exercise followed by 1 week of rest, and so on.
It is not recommended to do both 16-hour fasting and exercise for a long period of time because you want to rejuvenate faster.
There are many reasons why combining 16-hour fasting and exercise can be more effective in rejuvenating you. However, there is a possibility that by continuing the fast for a long period of time, the body may lack the necessary nutrients and autophagy may only lead to the breakdown of cells and not to their repair.

Nutrition and bodybuilding are important for rejuvenating effects.

There is a limit to the amount of energy the liver and muscles can store and the body's ability to repair itself. The source of youthful skin, body, and mind are all derived from adequate amounts of protein, vitamins, and minerals from the food we eat.
In order to maintain youthfulness, it is just as important, if not more important, to "nourish and build" the body as it is to "deprive the body of nutrients and destroy it.


In this article, we have summarized the recommended exercises and points to keep in mind during the 16-hour fast.
We hope you have found that all of these are the most powerful rejuvenation methods that can be implemented right now, without the need for special supplements or tools. We hope you will take up the challenge to keep your body and mind healthy and youthful for many years to come.

▶︎ related article "Dieting and Rejuvenation! How to Do the 16-Hour Fasting" ◀︎

Category List

Related Articles