Pavel Tsatsouline revisits the cost of adaptation:
According to Prof. Bayevsky, at any given moment, between 50 to 80% of all people are in the so-called donozoological state, or between health and illness. According to Academician Nikolay Amosov, these people are only “statically healthy” — until the environment disrupts their fragile status quo. Although they may be feeling fine, even a mild infection is potentially dangerous to them. Not the infection itself, but the complications from the strain it puts on the supply systems. You might know someone who died of a cardiac arrest while struggling with some other malady.
Say, Bob’s tissues need a gallon of blood a minute at rest and his heart can pump out 1,3 gallons per minute max, which is average — this is called the maximal cardiac output. Everything is fine and dandy — until the man goes to South America and catches typhoid fever. His energy requirements skyrocket, fighting a disease is not unlike performing hard labor. Typhoid fever doubles one’s oxygen consumption. The heart now has to pump two gallons of blood per minute. Except… its limit is only a gallon and a half. Bingo. The traveler returns home in the jet’s cargo bay in a body bag. The man died from failure of systems that were not even stricken by the disease. Had Bob cared to work on increasing their functional reserves, he would have survived.
Academician Amosov coined the term “the quantity of health”, or the sum of the reserve powers of the main functional systems. These reserve powers are measured with the health reserve coefficient, the ratio of the system’s maximal ability to the everyday demands on it.
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Obviously, to improve your quantity of health, you need to increase the reserves of your functional systems, cardiovascular, pulmonary, muscular, etc. There are over a hundred measurable health parameters. Individual adaptation has been defined as gradual development of resistance to a particular environmental stimulus that enables the organism to function in conditions earlier incompatible with life and meet challenges that previously could not be met (1). In other words, adaptation is about survival.
The path to health seems simple: train hard, increase your “quantity of health”, and live happily ever after. If Bob built up to the point of being able to swim non-stop for an hour a day, surely he would have built enough heart capacity to survive typhoid fever! Certainly — while making himself more vulnerable to other stressors…
A number of Soviet and Russian textbooks, from the 1970s until today, cite a study of young rodents undergoing an intense swimming regimen — one hour a day for ten weeks (2). Their heart mass increased — while the mass of their kidneys and adrenal glands went noticeably down, and so did the number of the liver cells. In other words, while the training increased the functional capacity of the heart, it simultaneously reduced the capacity of several inner organs! If later the “athletes” from the study encountered significant physical loads, they would be better prepared to handle them and survive compared to their untrained peers. If, on the other hand, the challenge were directed at the liver or kidneys (through a change of food, an increase of sodium intake, etc.), the hard training rats would be at a disadvantage compared to their lazy brothers and sisters…
This phenomenon is called “the cost of adaptation” (3). The cost can be exacted from the systems of the body directly loaded by the stressor — or from other system(s) not directly involved in dealing with the stressor (4).
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If you choose health, do not reach for Olympic medals, avoid narrow specialization, and train in moderation. Because high adaptation cost is experienced especially by specialist athletes and people who perform hard physical labor (6).
Soviet research teaches us that sport training and physical culture lead to a significant decrease in diseases overall and injuries (7). Renown Soviet scientist Prof. Zimkin concluded, “It has been determined from animal experiments and observation of human subjects that muscular activity increases the organism’s non-specific resistance to many unfavorable stressors people are subjected to in modern conditions, e.g. hypoxia, some poisons, radioactive materials, infections, overheating, overcooling, etc. A significant decrease in illnesses has been observed in people training for sport or practicing physical culture.” He went on to add that “rational” training is what is needed to deliver such resilience (8). Moderate physical loads stimulate the immune system (9).
(Hat tip to Mangan.)