acclimatization

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First report with membership list of the Acclimatisation Society of Great Britain (1861), a private society that called for the naturalization of non-resident species to enrich biodiversity

Under an acclimation or acclimatization refers to the individual physiological adaptation of an organism within its genetic instructions to changing environmental factors , which adjustment is even reversible (reversible).

Climate changeover

Animals

Adaptation to another climatic zone , in particular to unfamiliar temperature, humidity or UV index , means acclimatization to the climate (where the term "acclimatization" comes from). Regular physical training can help in preparation. The most important measures on site are appropriate clothing and reduced physical stress. On site, extended stays in temperature-controlled rooms support the conversion phase of the first one to two weeks. Special climatic zones require very different precautions: Regular drinking is important in arid climates and requires attention to fluid intake that goes beyond the need to drink, while in polar climates, attention must be paid to clothing that is well insulated. Switching from a temperate zone to a humid tropical climate zone is particularly difficult.

Acclimatization to higher temperatures occurs physiologically through lower pulse, reduced rectal temperature, the feeling of overexertion, increased plasma volume and increased perspiration as well as increased incorporation of proteins in cell membranes , including heat shock proteins . Increased pigment formation is an acclimatization effort to a higher UV index. Nevertheless, dermatologists and cancer specialists recommend constant protection with sunscreen.

The problem of climate change does not only affect mobile people. Just sessile life forms are faced with the challenge of climate change by Akklimatisationen (and possibly also by evolutionary adjustments to compensate), about corals when they are exposed to higher water temperatures. Fish are also exposed to changes in temperature and have developed corresponding adaptation mechanisms.

But pets that are exported to distant areas alive also need to acclimate. After moving from the temperate climate of Central Europe to the semi-arid tropical climate of northeast Brazil, cows at temperatures above 30 ° C were sprayed with water every hour for 10 minutes and fed twice a day. Under these conditions, their climate change took about a year and a half.

plants

Plants also have mechanisms of climate adaptation, especially seasonal adaptation; after all, they have to cope unconditionally with the conditions at their location.

Acclimatization to altitude in lung breathers

At high altitudes, not only is the amount of oxygen available in the earth's atmosphere lower, but also the oxygen partial pressure ( pO 2 ) and the air pressure . Among these three physicochemical parameters, the reduced oxygen partial pressure has been assigned the sole importance for physiological altitude problems since the beginning of the 20th century. A lower oxygen partial pressure results in a lower oxygen saturation ( sO 2 ) of the blood.

The early changes in unusual altitude are expressed in:

Without acclimatization, the condition can develop into altitude sickness . As a countermeasure in the event of slight complaints, it may be necessary to take a break or a (temporary) descent. In the case of serious complaints, a rapid permanent descent is necessary.

A well-trained body, for example through regular jogging, is a good prerequisite for altitude acclimatization . To prepare for greater heights, altitude training at a moderate altitude can be useful. A special training program can be completed at higher altitudes to increase performance at higher altitudes. However, the effectiveness of training at higher altitudes primarily comes from acclimatization during the training period.

Due to the different ability to hypoxic respiratory drive , an adjustment is individual. The adjustment process, which takes place in different stages, is not yet fully understood. First, the respiratory and cardiac output increases to counteract the reduced O 2 partial pressure. As a result, a respiratory alkalosis develops , which the trained body can usually compensate for. The alveolo-vascular reflex improves the oxygen exchange between the alveoli and pulmonary capillaries. The hemoglobin binding curve shifts to the right in the blood , weakened by the respiratory alkalosis. If the oxygen deficiency persists, after a few days at an unusual altitude, increased erythropoietin is released into the plasma. The so intensified erythropoiesis (blood formation) leads to the production of more erythrocytes . Due to the higher number of red blood cells, the oxygen uptake and transport capacity of the blood is effectively improved. The hematocrit rises sharply, which impairs the flow properties of the blood and increases the risk of thrombosis . At the same time, other adjustments are made, such as an increase in testosterone levels .

Due to the lowering of the critical oxygen partial pressure through chemosensory activated respiratory time volume increase, the organism of most mammals can usually only adapt permanently below 5000  m despite the increased erythrocytes produced , at higher altitudes the degradation of several body functions begins in the long term, unless there are also hereditary altitude adjustments.

Characteristics for a successful acclimatization are:

  • a resting heart rate returned to normal
  • endurance performance appropriate to training
  • deepened breathing at rest and under exertion
  • increased urination
  • adequate oxygen saturation of the blood.

Acclimatization in competitive sports

At least since the preparation for the 1968 Summer Olympics in Mexico City (2200 m) we have known that altitude training in sports with endurance elements has a positive effect on performance, especially in the top range. Since that time, systematic research has been carried out on altitude acclimatization, especially from the point of view of training under altitude conditions and performance in the lowlands. Since the loss of height adjustment, especially in competitions in tournaments, is faster than is desirable for the competition, artificial acclimatization through rooms and / or tents is now also used to preserve the adjustment for as long as possible despite competitions in the flatlands. The first such rooms were used in the former GDR in the Kienbaum sports school .

Adaptation to changing salinity in bony fish

Sessile as well as mobile aquatic organisms are sometimes, especially in the area of ​​inland lakes or estuaries without outflow , especially in tidal deltas , forced to adapt to changing temperature conditions and salt concentrations, often very quickly. Brackish water dwellers in particular are capable of doing this. The osmoregulation places high demands on the adaptability.

Prospective NASA astronauts acclimatise to weightlessness in a KC-135 aircraft during short parabolic flights under the guidance of Canadian space medicine specialist Douglas Watt (top left).

Adaptation to weightlessness

Adaptation to the state of weightlessness is possible for many non-aquatic organisms, although an evolutionary willingness to do so has hardly been developed. A lack of acclimatization to the conditions of weightlessness, combined with discomfort, is space sickness , which, similar to seasickness, is caused by a disturbance of the organ of equilibrium .

See also

Individual evidence

  1. ↑ KB Pandolf, RL Burse, RF Goldman: Role of physical fitness in heat acclimatisation, decay and reinduction . In: Ergonomics , Vol. 20, No. 4, April 1977, pp. 399-408, doi : 10.1080 / 00140137708931642 .
  2. ^ A b Lawrence E. Armstrong, Carl M. Maresh: The induction and decay of heat acclimatization in trained athletes . In: Sports Medicine , Vol. 12, No. 5, Nov. 1991, pp. 302-312.
  3. ↑ DocCheck Flexikon: Acclimatization , accessed November 23, 2019.
  4. ↑ Thomas Schwarz: The latest findings on photoprotectors . In: Hautnah Dermatologie , Vol. 34, Supplement 1, February 2018, pp. 6-11.
  5. ^ Anna Wilm, Mark Berneburg: Sun protection . In: Aesthetic dermatologie & kosmetologie , Vol. 8, No. 4, August 2016, pp. 34–40.
  6. ↑ Barbara E. Brown, Andrew R. Cossins: The potential for temperature acclimatization of reef corals in the face of climate change . In: Z. Dubinsky, N. Stambler (eds.): Coral Reefs: An Ecosystem in Transition , Springer, Dordrecht 2010, pp. 421–433, doi : 10.1007 / 978-94-007-0114-4_24 , ISBN 978- 94-007-0114-4 .
  7. ↑ Ian A. Johnston, Jeff Dunn: Temperature acclimatisation and metabolism in ectoderms with particular reference to Teleost fish . In: Symposia of the Society for Experimental Biology , Vol. 41, February 1987, pp. 67-93.
  8. ↑ B. Bényei, A. Gáspárdy, WC Barros: Changes in embryo production results and ovarian recrudescence during the acclimatisation to the semiarid tropics of embryo donor Holstein – Friesian cows raised in a temperate climate . In: Animal Reproduction Science , Vol. 68, No. 1, October 2001, pp. 57-68, doi : 10.1016 / S0378-4320 (01) 00144-0 .
  9. ↑ Owen K.Atkin, Mark G.Tjoelker: Thermal acclimation and the dynamic response of plant respiration to temperature . In: Trends in Plant Science , Vol. 8, No. 7, July 2003, pp. 343-351, doi : 10.1016 / S1360-1385 (03) 00136-5 .
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  11. ↑ JS Haldane, AM Kellas, EL Kennaway: Experiments on acclimatisation to reduced atmospheric pressure . In: The Journal of Physiology , Vol. 53, No. 3-4, December 3, 1919, pp. 181-206, doi : 10.1113 / jphysiol.1919.sp001870 .
  12. ^ Benjamin D. Levine, James Stray-Gundersen: “Living high-training low”: effect of moderate-altitude acclimatization with low-altitude training on performance . In: J. Appl. Physiol. , Vol. 83, No. 1, July 1997, pp. 102-122, doi : 10.1152 / jappl.1997.83.1.102
  13. ^ Bo Berglund: High-altitude training . In: Sports Medicine , Vol. 14, No. 5, Nov. 1992, pp. 289-303.
  14. ^ Benjamin D. Levine, James Stray-Gundersen: The effects of altitude training are mediated primarily by acclimatization, rather than by hypoxic exercise . In: Robert C. Roach, Peter D. Wagner, Peter H. Hackett: Hypoxia: From Genes to the Bedside , Kluwer Academic / Plenum Publishers, New York 2001, Chapter 7, pp. 75-88 ( PDF ).
  15. ↑ Peter H. Albrecht, Judith K. Littell: Plasma erythropoietin in men and mice during acclimatization to different altitudes. In: J. Appl. Physiol. , Vol. 72, No. 1, January 1972, doi : 10.1152 / jappl.1972.32.1.54 .
  16. ↑ a b Ferran Rodríguez, Héctor Casas, Mireia Casas, Teresa Pagés, Ramón Rama, Antoni Ricart, Josep Ventura, Jordi Ibáñez, Ginés Viscor: Intermittent hypobaric hypoxia stimulates erythropoiesis and improves aerobic capacity . In: Med. Sci. Sports Exerc. , Vol. 31, No. 2, 1999, pp. 264-268, doi : 10.1097 / 00005768-199902000-00010 .
  17. ↑ GF Gonzales: [Hemoglobin and testosterone: importance on high altitude acclimatization and adaptation] . In: Revista Peruana de Medicina Experimental y Salud Publica , Vol. 28, No. 1, March 2011, pp. 92-100, doi : 10.1590 / s1726-46342011000100015 (in Spanish).
  18. ↑ JP Richalet, JC Souberbielle, AM Antezana, M. Dechaux, JL Le Trong, A. Bienvenu, F. Daniel, C. Blanchot, J. Zittoun: Control of erythropoiesis in humans during prolonged exposure to the altitude of 6.542 m . In: American Journal of Physiology , Vol. 266, No. 3, March 1994, doi : 10.1152 / ajpregu.1994.266.3.R756 .
  19. ↑ JL Rupert, PW Hochachka: Genetic approaches to understanding human adaptation to altitude in the Andes . In: Journal of Experimental Biology Vol. 204, 2001, pp. 3151-3160, ( PDF ).
  20. ↑ Arnd Krüger (2020): Altitude training. Performance sports 50, 1, 25-27.
  21. ↑ The Lexicon of the Earth: Brackish Water