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Neither cloud cover nor low solar loads are associated with fast marathon performance
Matthew R Ely1, Samuel N Cheuvront, Scott J Montain
1US Army Research Institute of Environmental Medicine, Natick, MA 01760-5007, USA. matthew.ely@us.army.mil
Medicine and Science in Sports and Exercise
|November 8, 2007
Summary
Cloud cover and low solar radiation do not improve marathon times. Optimal marathon performance is linked to cool ambient temperatures around 12 degrees C, regardless of cloud or sun conditions.
Area of Science:
- Sports Science
- Environmental Physiology
- Athletic Performance Analysis
Background:
- A common belief suggests cloud cover and low solar radiation enhance marathon performance.
- This notion is prevalent in anecdotal reports, running literature, and scientific publications.
- A comprehensive review of this popular belief is lacking.
Purpose of the Study:
- To investigate the association between cloud cover, low solar load, and fast marathon times.
- To characterize the typical weather conditions during elite marathon performances.
- To compare the environmental conditions of the fastest men's and women's marathons.
Main Methods:
- Analysis of finishing times and weather data for elite marathon performances.
- Included are winning times from North American marathons, all-time fastest times, and Olympic marathons.
- Data encompassed both men's and women's events.
Main Results:
- Cloud cover showed no significant association with fast marathon times (Odds Ratios: 0.68 M; 0.51 F).
- Low solar load was not linked to faster marathon performances (Odds Ratios: 1.4 M; 1.3 F).
- The primary factor correlated with fast marathons was cool ambient temperature (10.6–13.6 degrees C).
Conclusions:
- Cloud cover and low solar load do not increase the likelihood of achieving a fast marathon time.
- The fastest marathon performances consistently occur in cool temperatures, around 12 degrees C.
- These optimal temperature conditions appear consistent for both male and female elite marathon runners.
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