Impact of environmental parameters on marathon running performance

• Published in: PloS one Vol. 7; no. 5; p. e37407
• Main Authors: El Helou, Nour, Tafflet, Muriel, Berthelot, Geoffroy, Tolaini, Julien, Marc, Andy, Guillaume, Marion, Hausswirth, Christophe, Toussaint, Jean-François
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 23-05-2012; Public Library of Science (PLoS)
• Subjects: Air Pollutants - analysis; Air pollution; Air temperature; Analysis; Athletes; Atmospheric Pressure; Biology; Biomedical research; Chemistry; Data processing; Dew point; Earth Sciences; Endurance; Environment; Environmental conditions; Environmental factors; Environmental impact; Environmental parameters; Environmental protection; Epidemiology; Humanities and Social Sciences; Humans; Humidity; Impact analysis; Marathons; Mathematical models; Medicine; Mens health; Microclimate; Models, Theoretical; Nitrates - analysis; Nitrogen dioxide; Outdoor air quality; Ozone; Ozone - analysis; Particulate Matter; Pollutants; Race; Races; Runners (Sports); Running; Running - physiology; Sea level; Sport; Sport physiology; Sports - statistics & numerical data; Statistics, Nonparametric; Sulfates - analysis; Sulfur dioxide; Temperature; Temperature effects; Temperature rise; Women; France
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0037407

The objectives of this study were to describe the distribution of all runners' performances in the largest marathons worldwide and to determine which environmental parameters have the maximal impact.
We analysed the results of six European (Paris, London, Berlin) and American (Boston, Chicago, New York) marathon races from 2001 to 2010 through 1,791,972 participants' performances (all finishers per year and race). Four environmental factors were gathered for each of the 60 races: temperature (°C), humidity (%), dew point (°C), and the atmospheric pressure at sea level (hPA); as well as the concentrations of four atmospheric pollutants: NO(2)-SO(2)-O(3) and PM(10) (μg x m(-3)).
All performances per year and race are normally distributed with distribution parameters (mean and standard deviation) that differ according to environmental factors. Air temperature and performance are significantly correlated through a quadratic model. The optimal temperatures for maximal mean speed of all runners vary depending on the performance level. When temperature increases above these optima, running speed decreases and withdrawal rates increase. Ozone also impacts performance but its effect might be linked to temperature. The other environmental parameters do not have any significant impact.
The large amount of data analyzed and the model developed in this study highlight the major influence of air temperature above all other climatic parameter on human running capacity and adaptation to race conditions.