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Genetic Influence on High Altitude Performance
- Vivek Kakar, Rashmi Kumar (21 December 2007)
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Is 2500m too high?
- R A Alanko (26 December 2007)
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The need for analysis of performance during match-play
- Chris Carling (27 December 2007)
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Football and altitude: It is worse to play the day of arrival
- Gustavo F. Gonzales (23 January 2008)
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"¨Football and physiological performance at high altitude, the ¨PLAN B"
- Jorge R. FLORES (19 March 2008)
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Effect of altitude on football performance
- Peter Bärtsch, Jiri Dvorak, and Bengt Saltin (19 November 2008)
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Vivek Kakar, Specialist Registrar Anaesthesia University Hospital Lewisham, London, Rashmi Kumar
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Editor - We were delighted to read this well conducted and rather refreshing study bringing together core physiology and popular sports. Although longstanding acclimatization of the players’ resident at high altitudes does offer them a significant physiological advantage for the reasons highlighted in the study but we would also like to point out the role of genetic makeup in once performance at high altitude. This has been a focus of large number of recent studies1,2,3,4 and there is evidence now to suggest that genetic polymorphism for genes encoding ACE I/D, AT II (Type 1) receptor and eNOS amongst others plays a significant role in determining once performance as well as susceptibility to High Altitude Pulmonary Oedema (HAPE resistant versus HAPE susceptible). It has been postulated that successful marathon runners and mountain climbers who otherwise reside at low altitude but still perform significantly well under unaccustomed situations may be related to these factors. We agree that the option of reaching the destination early and maximising acclimatization is not feasible but once the role of these genetic factors is established by way of larger studies, it may be possible to screen players for their high altitude performance or endurance. Also, since we are talking about a population confined to a single geographical area with altitude being the major difference, it is difficult to rule out the influence of migration of such population within the region and their variable high or low altitude ancestry. In this context it is also important to note that with commercialisation of the sports more and more sportsmen from South America are coming to play football in Europe and in fact spending major part of the year here. Whether this leads to deconditioning or not, to what extent over how long is not clearly understood. References 1. Montgomery HE, Marshall R, Hemingway H, et al. Human gene for physical performance. Nature 1998; 393:221–222 2. Yunden Droma, Masayuki Hanaoka, Masao Ota, et al. Positive Association of the Endothelial Nitric Oxide Synthase Gene Polymorphisms With High-Altitude Pulmonary Edema. Circulation. 2002;106:826 3. Katsuyama, Masao Ota, Toshio Kobayashi, Junichi Hotta, et al. Polymorphisms of Renin-Angiotensin System Genes in Japanese Subjects with High-Altitude Pulmonary Edema. Chest 2004;126;825-830 4. Rupert, Jim L., and Michael S. Koehle. Evidence for a genetic basis for altitude-related illness. High Alt. Med. Biol. 7:150–167, 2006. Competing interests: None declared |
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R A Alanko, Family Physician 97814
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Excellent study and greatly appreciated. The next step for this USA fan is for FIFA to lower the altitude limit to 2000m (Azteca Stadium in Mexico City is at approx 2250m). Competing interests: USA fan |
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Chris Carling, Head Sports Scientist Lille Football Club (France)
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I thoroughly enjoyed reading this article which will no doubt encourage researchers to build upon this existing research by exploring some of the questions identified in this paper. I do however feel that somewhere along the line a tactical analysis of play and physiological analysis of movement during actual competition is required to build on our existing knowledge of the effects of altitude on athletic performance. It has previously been suggested that altitude would affect player work-rates during competition as their aerobic capacity is reduced.1 An analysis of work-rate information during match-play such as the distance run and high- intensity activity of players not normally used to playing at altitude would provide objective information on any possible reduction in performance. It could also be used in planning work-rest strategies for playing at altitude, with a view towards timing short periods in the game for recovery to take place. Similarly, it would be useful to examine the performance of teams such as Bolivia when they play at sea-level compared to at altitude to examine whether they have a physical advantage over other teams. Finally, a future study could also be pertinent for exploring the results at altitude of teams from other continents not used to playing in such conditions. References 1. Carling, C, Williams, A & Reilly, T. (2005) The Handbook of Soccer Match Analysis. London: Routledge, 2005 Competing interests: None declared |
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Gustavo F. Gonzales, Dean of the Faculty of Sciences and Philosophy Universidad Peruana Cayetano Heredia. Av. Honorio delgado 430. Lima 31, Peru
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Dear Editor In BMJ 2007; 335: 1278-1281, it was published an interesting article regarding the effect of altitude on physiological performance using scores of international football games (1). In his conclusions the author indicates that altitude provides a significant advantage for high altitude teams when playing international football games at both low and high altitudes. The author also refers that the International Football Association (FIFA) Sport Medicine Commission recommends that football matches above 3000 m should be played only after an acclimatization period of 10 days because of the acute effect of altitude on performance (1). This is not strictly true. In fact, in 1998 I published a book on football and acclimatization to high altitude based on our participation in the process of acclimatization of the Peruvian National Football team for the eliminatory round competition of the World Football Cup (France, 1998). In one chapter (2), we analyzed results and scores of international football games played by the Bolivian National Football team between 1950 and 1993 against other Latin American or European teams. According to this study, 0% of the lowland teams won a game if they play the same day of their arrival. However, lowland teams won 40%, 60% and 50% of the games after 1, 2 or 3 days of acclimatization, respectively. In a logistic regression analysis including as independent variables days of acclimatization, kind of game (competition vs. friendly) and previous experience at high altitudes in the same year, the only variable associated to the probability of winning a football game was days of acclimatization. The percentage of home wins was 82% when visitors play the same day of their arrival to high altitude whereas this percentage was reduced to 40-50% if visitors were acclimatized from 1-3 days. This is less than the 53.7% of home wins described by McSharry (1) for two teams from the same altitude. This suggests that it is not necessary to wait 10 days to be able to win a game at high altitude and that the probability of the Bolivian National team of winning a football game was lower than the average for South American football teams. I have also assessed the number of goals scored and conceded. At 3600 m, the Bolivian National team has a ratio of 3.83 goals scored/goals conceded. This value was reduced to 1.02, 1, and 1.2 after 1, 2 or 3 days of acclimatization of the opponent team. In 1996 a plan for acclimatization to high altitude was performed to the Peruvian National Football team. Thirty five percent of the players of the Peruvian National team developed acute mountain sickness (AMS) within 6 hours after arrival to Cuzco (3400 m). The study demonstrated that occurrence of AMS did not predict a low performance in physical activity at high altitude (3). Data suggest that at least with one day of acclimatization the probability of winning at altitude was similar to any other away games, and that AMS was not related to performance during the game if players have been acclimatized at least by one day. In our experience, the conclusion that altitude provides a significant advantage for high altitude teams when playing football games from low altitudes (1) is not consistent at all. For instance, people from high altitudes who descend to sea level have a blood volume and red cell mass that are excessive for their new environment and a process of neocytolysis is observed (4). This results in a rapid decrease in hemoglobin concentration. At sea level, reticulocyte production continues unchanged in the first few days not decreasing until day 8 in response to ongoing erythropoietin suppression. Decrease in red cell mass as reticulocyte production remains normal provides conclusive evidence of a hemolytic process. In turn this may affect athletic performance. In Peru, since 1961 the National Football Cup includes teams from sea level and those from 2000 to 4340 m. It is a well known fact that the chances of a high altitude team at low altitude are in general much lower. Mc Sharry´s article should include days of acclimatization in his statistical analysis to demonstrate that at high altitude is much worse to play the same day of arrival but it is not necessary to wait 10 days to play a football game. Gustavo F. Gonzales. D.Sc; M.D Specialist in Endocrinology Instituto de Investigaciones de la Altura (High Altitude Research Institute) and Faculty of Sciences and Philosophy. Universidad Peruana Cayetano Heredia, 430 Av. Honorio Delgado, Lima 31, Peru. ggr@upch.edu.pe References 1. McSharry PE. Effect of altitude on physiological performance: a statistical analysis using results of international football games. BMJ 2007; 335: 1278-1281. 2. Gonzales GF, Villena A. Football and altitude: The eliminatories of the world cups [in Spanish]. In Football and acclimatization to altitude. Universidad Peruana Cayetano Heredia: Lima. 1998:99-112. 3. Gonzales GF, Villena A, Aparicio R. Acute Mountain Sickness: Is there a lag period before symptoms?. American Journal of Human Biology. 1998;10: 669-677. 4. Rice L, Ruiz W, Driscoll T, Whitley CE, Tapia R, Hachey DL, Gonzales GF, Alfrey CP. Neocytolysis on descent from altitude: A newly recognized mechanism for the control of red cell mass. Annals of Internal Medicine. 2001; 134: 652-656. Competing interests: None declared |
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Jorge R. FLORES, Club Blooming adviser, Foot ball Clinica Niño Jesus, P.O.Box 3225, Santa Cruz, Bolivia
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"¨Football and physiological performance at high altitude, the ¨PLAN B" article ID: 335/7633/1278 Dr. Patrick E McSharry BMJ - ENGLAND Dr. Mc Sharry, Subjet: a copy of my paper in English My name is Dr. Jorge Flores. I am a physician from Bolivia involved in football. We have published an article* regarding the effect of altitude on physiological performance. I am happy to share with you that we have found absolute similarities between data and results from your study ¨Effect of altitude on physiological performance: a statistical international analysis using results of football games¨ which was published on Dec 20, 2007 in the Medical and Statistical Results section of British Medical Journal: BMJ 2007; 335: 1278-1281, and the Bolivian ¨Plan B– Análisis Médico y estadístico Multivariante" , published by JP Suarez and myself on Oct 12, 2007. In October 12, 2007 we presented an study of 3564 matches of the Bolivian Professional League (LFPB), national professional championship from 1978 to 2002, between teams of High Altitude (HA) and teams from Low Altitude (LA). The teams of HA, when playing at HA won 80%, tied 16 % and lost only 4%. The same teams of HA when playing at LA lost 64%, tied 21% and lost 15% of the games. The conclusion is that HA teams when playing at home (home + altitude) have a very significant statistical advantage and better performance, and when playing at LA, the HA team have only the normal visitor disadvantage seen all over the world. The laboratory findings ** shows that HA players when playing as local in HA, have 20% more Aerobic Capacity, 20 % more Anaerobic Capacity and 12 % and deviation to the left of Lactate scale, with 10% better VO2 compsumtion, 20% less Heart Rate and, 20% more RBC, Hb and Htc and as consequence 25% better physiological performance than LA teams. Both, your study and ours, demonstrate that physiological performance of teams from cities of LA is lower when they play at HA due to Hypoxia. Therefore, both studies validate the effect that HA has to teams from low LA cities. To improve the performance of LA teams we propose to increase the number of substitutions of player during the game ( this is the thesis and proposal of our "Plan B".) I will be thankful if you can read our work which can be found below. Looking forward to hear back from you. Dr. Jorge Flores, M.D.*** <jflores04@hotmail.com> http://www.galenored.com/jflores PLAN "B" – Análisis Médico y estadístico Multivariante" para partidos de fútbol a más y menos de 2500m de Altitud, , by Jorge FLORES, Juan Pablo SUAREZ and al., Medical College Meeting, Oct 12, 2007. **Performance of Altitude Acclimatized and Non-Acclimatized Professional Football (Soccer) Players at 3,600 M, TOM D. BRUTSAERT1, HILDE SPIELVOGEL2, RUDY SORIA2, MAURICIO ARAOZ2, ESPERANZA CACERES2, GILIANE BUZENET3, MERCEDES VILLENA2, MARIO PAZ ZAMORA4, and ENRIQUE VARGAS2 1Cornell University, Ithaca, New York; 2Instituto Boliviano de Biología de Altura, La Paz, Bolivia; 3Université Claude Bernard, Lyon I, France; 4Federación Boliviana de Futbol, La Paz, Bolivia. *** President of Tahuichi Football Academy Past President, Federación Boliviana de Footba<P> Medical Adviser, Football, Blooming Club Santa Cruz, Bolivia Competing interests: None ----- Original Message ----- From: Jorge R. FLORES Aguilera To: Jorge Flores ; Jorge FLORES Aguilera ; jflores04@hotmail.com Sent: Friday, February 29, 2008 12:35 PM Subject: FW: Altitude and football, answer of Patrick@mcsharry.net Date: Fri, 29 Feb 2008 15:38:21 +0000 From: patrick@mcsharry.net To: jflores04@hotmail.com Subject: Altitude and football Dear Dr Flores, I was delighted to receive your email about your study which supports the results of my BMJ paper. Do you happen to have a copy of your paper in English? Regards, Patrick Competing interests: None |
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Peter Bärtsch, Prof. of Sports Medicine, Head of Div. of Sports Medicine Medical University Clinic, Im Neuenheimer Feld 410, D-69120 Heidelberg, Germany, Jiri Dvorak, and Bengt Saltin
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Sir, As editors of a recently published supplement on football and altitude1, which contains review papers based on presentations given by experts in the field at a consensus meeting, we feel obliged to bring to your attention a re-analysis of data published in the British Medical Journal2. In this paper McSharry analyzed the results of the qualification games for the world championships over the last 104 years in South America and demonstrated in figure 2 that high altitude teams had an advantage from playing at low altitude. This conclusion was questioned as being inconsistent with the understanding of altitude physiology and physics presented at the consensus meeting1, which promoted McSharry to re-analyze the data with a non-linear model. The result of this re-analysis, which is shown in figure 1 of the paper of Gore et al.3 published in the supplement, indicates that when two teams are from the same altitude, the probability of the home team winning was 0.50, but this increased to 0.57 if a team from an altitude of 3600 m played at home against a team from sea level. However, the probability of a home win even rose to 0.73 for a team from sea level at home against a team from 3600 m. These discrepant outcomes of modelling the same data set demonstrate that the outcome of such analysis depends very much on the model that is used and possibly also on additional assumptions or corrections that are made. Peter Bärtsch, Dept. of Internal Medicine, Div. of Sports Medicine, Medical University Clinic, Heidelberg, Germany peter.bartsch@med.uni-heidelberg.de Jiri Dvorak, Dept. of Neurology/Neurophysiology, Schulthess-Clinic, Zurich, Switzerland Bengt Saltin, Copenhagen Muscle Research Centre (CMRC), University Hospital, Copenhagen, Denmark Competing interests: None declared 1. Bärtsch P, Dvorak J, Saltin B. Special Issue: Football and Altitude. Scand J Med Sci Sports 2008; 18(Suppl.1):1-99. 2. McSharry PE. Effect of altitude on physiological performance: a statistical analysis using results of international football games. BMJ 2007; 335:1278-81. 3. Gore CJ, McSharry PE, Hewitt AJ, Saunders PU. Preparation for football competition at moderate to high altitude. Scand J Med Sci Sports 2008; 18(Suppl 1):85-95. Competing interests: None declared |
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