45
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Impact of Environmental Parameters on Marathon Running Performance

      research-article

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Purpose

          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.

          Methods

          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.m −3).

          Results

          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.

          Conclusions

          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.

          Related collections

          Most cited references72

          • Record: found
          • Abstract: found
          • Article: not found

          Impact of weather on marathon-running performance.

          Marathon running performance slows in warm weather conditions, but the quantitative impact of weather has not been established. To quantify the impact of weather on marathon performance for different populations of runners. Marathon results and weather data were obtained for the Boston, New York, Twin Cities, Grandma's, Richmond, Hartford, and Vancouver Marathons for 36, 29, 24, 23, 6, 12, and 10 yr, respectively. The race results were broken into quartiles based on the wet-bulb globe temperature (Q1 5.1-10 degrees C, Q2 10.1-15 degrees C, Q3 15.1-20 degrees C, and Q4 20.1-25 degrees C). Analysis of the top three male and female finishers as well as the 25th-, 50th-, 100th-, and 300th-place finishers were compared with the course record and then contrasted with weather. Marathon performances of top males were slower than the course record by 1.7 +/- 1.5, 2.5 +/- 2.1, 3.3 +/- 2.0, and 4.5 +/- 2.3% (mean +/- SD) for Q1-Q4, respectively. Differences between Q4 and Q1, Q2, and between Q3, and Q1 were statistically different (P < 0.05). The top women followed a similar trend (Q1 3.2 +/- 4.9, Q2 3.2 +/- 2.9, Q3 3.8 +/- 3.2, and Q4 5.4 +/- 4.1% (mean +/- SD)), but the differences among quartiles were not statistically significant. The 25th-, 50th-, 100th-, and 300th-place finishers slowed more than faster runners as WBGT increased. For all runners, equivalence testing around a 1% indifference threshold suggests potentially important changes among quartiles independently of statistical significance. There is a progressive slowing of marathon performance as the WBGT increases from 5 to 25 degrees C. This seems true for men and women of wide ranging abilities, but performance is more negatively affected for slower populations of runners.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Impaired exercise performance in the heat is associated with an anticipatory reduction in skeletal muscle recruitment.

            Exercise in the heat causes "central fatigue", associated with reduced skeletal muscle recruitment during sustained isometric contractions. A similar mechanism may cause fatigue during prolonged dynamic exercise in the heat. The aim of this study was to determine whether centrally regulated skeletal muscle recruitment was altered during dynamic exercise in hot (35 degrees C) compared with cool (15 degrees C) environments. Ten male subjects performed two self-paced, 20-km cycling time-trials, one at 35 degrees C (HOT condition) and one at 15 degrees C (COOL condition). Rectal temperature rose significantly in both conditions, reaching maximum values at 20 km of 39.2+/-0.2 degrees C in HOT and 38.8+/-0.1 degrees C in COOL (P<0.005 HOT vs. COOL). Core temperatures at all other distances were not different between conditions. Power output and integrated electromyographic activity (iEMG) of the quadriceps muscle began to decrease early in the HOT trial, when core temperatures, heart rates and ratings of perceived exertion (RPE) were similar in both conditions. iEMG was significantly lower in HOT than in COOL at 10 and 20 km, while power output was significantly reduced in the period from 80% to 100% of the trial duration in the HOT compared with COOL condition. Thus, reduced power output and iEMG activity during self-paced exercise in the heat occurs before there is any abnormal increase in rectal temperature, heart rate or perception of effort. This adaptation appears to form part of an anticipatory response which adjusts muscle recruitment and power output to reduce heat production, thereby ensuring that thermal homeostasis is maintained during exercise in the heat.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Effects of ambient temperature on the capacity to perform prolonged cycle exercise in man.

              Eight healthy males performed four rides to exhaustion at approximately 70% of their VO2max obtained in a neutral environment. Subjects cycled at ambient temperatures (Ta) of 3.6 +/- 0.3 (SD), 10.5 +/- 0.5, 20.6 +/- 0.2, and 30.5 +/- 0.2 degrees C with a relative humidity of 70 +/- 2% and an air velocity of approximately 0.7 m.s-1. Weighted mean skin temperature (Tsk), rectal temperature (Tre), and heart rate (HR) were recorded at rest, during exercise and at exhaustion. Venous samples were drawn before and during exercise and at exhaustion for determination of hemoglobin, hematocrit, blood metabolites, and serum electrolytes and osmolality. Expired air was collected for calculation of VO2 and R which were used to estimate rates of fuel oxidation. Ratings of perceived exertion (RPE) were also obtained. Time to exhaustion was significantly influenced by Ta (P = 0.001): exercise duration was shortest at 30.5 degrees C (51.6 +/- 3.7 min) and longest at 10.5 degrees C (93.5 +/- 6.2 min). Significant effects of Ta were also observed on VE, VO2, R, estimated fuel oxidation, HR, Tre, Tsk, sweat rate, and RPE. This study demonstrates that there is a clear effect of temperature on exercise capacity which appears to follow an inverted U relationship.
                Bookmark

                Author and article information

                Contributors
                Role: Editor
                Journal
                PLoS One
                PLoS ONE
                plos
                plosone
                PLoS ONE
                Public Library of Science (San Francisco, USA )
                1932-6203
                2012
                23 May 2012
                : 7
                : 5
                : e37407
                Affiliations
                [1 ]IRMES (bioMedical Research Institute of Sports Epidemiology), INSEP, Paris, France
                [2 ]Université Paris Descartes, Sorbonne Paris Cité, Paris, France
                [3 ]Faculté de Pharmacie, Département de Nutrition, Université Saint Joseph, Beirut, Lebanon
                [4 ]INSERM, U970, Paris Cardiovascular Research Center – PARCC, Paris, France
                [5 ]Research Department, INSEP, Paris, France
                [6 ]Hôtel-Dieu Hospital, CIMS, AP-HP, Paris, France
                Universidad Europea de Madrid, Spain
                Author notes

                Conceived and designed the experiments: JFT NEH GB AM. Analyzed the data: JT GB AM NEH MG MT. Wrote the paper: NEH GB JFT. Reviewed the paper: CH JFT.

                Article
                PONE-D-12-05741
                10.1371/journal.pone.0037407
                3359364
                22649525
                2fba5140-b0e0-4564-9895-441641cd595a
                El Helou et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
                History
                : 28 February 2012
                : 19 April 2012
                Page count
                Pages: 9
                Categories
                Research Article
                Biology
                Population Biology
                Epidemiology
                Environmental Epidemiology
                Chemistry
                Environmental Chemistry
                Pollutants
                Earth Sciences
                Atmospheric Science
                Atmospheric Chemistry
                Ozone
                Environmental Sciences
                Medicine
                Mental Health
                Psychology
                Behavior
                Human Performance
                Public Health
                Environmental Health
                Sports and Exercise Medicine

                Uncategorized
                Uncategorized

                Comments

                Comment on this article