I remember the first time I saw the slogan "charge for 5 minutes and talk for 2 hours", I immediately thought of those children who were alive and kicking all day. They are almost tireless in playing. They will be noisy in scenic spots or playgrounds until all the electricity is consumed. Then, in their parents’ arms or in the back seat of the car, they are still drinking or talking one second and falling asleep the next.
Next, it may often take only an hour to rest, and they can "resurrect with blood" and continue to play wildly. The reason why the baby is so tired is also a great reason.
However, although we all know this feature of children, do you know the reasons behind it? Why is there so much energy in their small bodies?
Comparable to triathletes.
At present, the most famous research on the amazing potential of children in anti-fatigue is an experiment done by researchers at the University of clermont-ferrand: they recruited three groups of volunteers, each with 12 people, who were national male athletes engaged in triathlon, cycling or long-distance running; 12 boys with an average age of 10 and a half; And 12 ordinary adult men who rarely engage in strenuous exercise participated in the study.
These three groups of volunteers were asked by the researchers to do two sets of 7-second cycling sprints, and then pedal their bicycles as soon as possible for 30 seconds.
After exercise, the researchers compared the energy production of different groups of volunteers, including aerobic exercise and anaerobic exercise. Among them, anaerobic exercise does not consume oxygen, but will produce a lot of lactic acid, which will cause muscle fatigue.
After that, the researchers compared the recovery rate of heart rate, blood oxygen level and lactate clearance rate of different groups of volunteers after exercise. Finally, the researchers found that children are not easily exhausted by cycling, which is equivalent to the fatigue of professional athletes.
In fact, in all tests, children’s physiological function performance is better than that of untrained adults, and their physical strength recovery speed is faster than that of professional athletes.
Muscle structure has advantages.
Although the experimental results are surprising, this advantage of children’s undeveloped body is not accidental, it is the result of children’s special body structure.
Don’t treat children as miniature adults, they are all "Little Superman" — — As far as muscle composition is concerned, children’s muscles are composed of 70% red muscle fibers and 30% white muscle fibers, while in adults’ bodies, red and white muscles account for 50% respectively.
This particularity of muscle structure means two completely different energy production mechanisms. White muscle fibers are mainly supplied with energy through anaerobic, that is, creatine phosphate (a high-energy molecule) and sugar (glucose) are directly supplied with energy, which can make muscles release strong explosive force in a short time. In contrast, red muscle fibers are powered by aerobic respiration.
Red muscle contains a large number of "small factory" mitochondria, which can use more oxygen and make the production more efficient. Therefore, although it is inferior to white muscle in explosive power and strength, red muscle has stronger endurance.
If an adult still has a lot of red muscle fibers, it is mostly inherited or the result of high-intensity training. But children do not benefit from training, but are born to be comparable to endurance athletes.
Small body shape is more divided
Children’s infinite energy not only comes from their unique muscle structure, but also benefits from their small body shape, which makes them have an extremely fast oxygen supply speed before their height soars in adolescence, and can deliver oxygen to all motor muscles in a short time to provide energy in time.
"It’s like the difference between a mouse and an elephant. Mice are small in size and have high oxygen demand, mainly relying on aerobic energy supply system; Elephants that are huge and bulky rely on anaerobic energy supply systems. " Sebastian Ratel, the leader of the research project, said, "In small animals, it takes much shorter time to transport oxygen."
As for the recovery speed, the experiment shows that the recovery rate of heart rate in children’s group is 85%, that of athletes is 60%, and that of untrained adults is only 40%.
Researchers attribute this outstanding performance of children to a more effective acetylcholine inhibition mechanism — — This neurotransmitter can slow down the beating speed of the heart through the parasympathetic nervous system (controlling the autonomous operation of the body).
Children also have outstanding performance in removing metabolic waste from the body. You know, metabolic waste is the culprit that disturbs muscle contraction. The research team tested the content of lactic acid in the blood of the tester — — Lactic acid is a metabolite produced by muscle fatigue. The test results show that compared with endurance athletes, children’s lactic acid disappears faster, and ordinary adults are far behind in this respect.
"Lightning speed" is the wonder of researchers for children’s physical recovery ability. They analyzed that this may be because children are smaller and their muscles are closer to the oxygen-rich blood pumped by the heart, so they can use oxygen more effectively. Children’s extra energy comes from slow muscle fibers, which contract slowly, protecting children from being injured by excessive exercise.
No need to exercise deliberately.
Although the metabolic ability is not limited by body shape, children’s legs are not strong enough, coordination is insufficient, and the toughness repair ability of tendon system is weak, which leads to low body efficiency and limited mechanical movement ability. It is true that children’s quick recovery makes people feel never tired, but it is not the case when they exercise for a long time.
After children enter adolescence, their bodies gradually turn to rely on anaerobic system, which, like their adult parents, makes them tired easily and slows down their recovery. Therefore, before puberty comes, it is best to focus on cultivating their sports skills and action effectiveness through coordinated exercise and motor function exercise, so as to improve sports efficiency, rather than focusing on improving aerobic metabolism, because children’s aerobic metabolism efficiency is already very high.
Therefore, there is no need to deliberately do aerobic exercise in childhood. On the contrary, from adolescence, it is necessary to continuously improve the motor function and efficiency of the body. Since children’s bodies grow rapidly and have a brand-new body cognition after entering adolescence, it is necessary to focus on improving aerobic metabolism at this time to maintain the body’s rapid recovery ability, delay the onset of fatigue, and prevent diabetes, obesity, insulin resistance and cardiovascular diseases.
Mentality and sleep also help.
In addition to the characteristics of physiological function, children’s mentality is a model of "living in the present". They devote themselves wholeheartedly to the present activities, crying if they want to, smile happily, naive and carefree, while we adults bear all kinds of pressures and worries of life every day, and have a lot of depressed negative emotions, which is also a great consumption of physical vitality and energy.
Needless to say, children can generally get much more abundant sleep recovery time than adults. According to the statistics of national data, the average sleep time of children under 5 years old is 10 ~ 12 hours, which is beyond our adults’ reach. (brown squirrel)