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Published on: October 17, 2018
Differential impacts of trail and ultra-trail running on cytokine profiles: An observational study
Sarah Skinner1,2, Elie Nader1,2, Emeric Stauffer1,2,3
1Laboratoire Interuniversitaire de Biologie de la Motricité (LIBM) EA7424, Team "Vascular Biology and Red Blood Cell", Université Claude Bernard Lyon, Université de Lyon, Lyon, France.
Background:
Endurance running events are known to cause inflammation and result in increased cytokine production. However, the effects of ultramarathons on cytokine profiles are not well characterized.
Objective:
The aim of this study was to describe and compare the effects of a trail (40 km) race and an ultra-trail (171 km) race on leukocyte concentrations and cytokine profiles.
Methods:
The study was conducted during the Ultra-Trail du Mont Blanc® ultra-marathon running event, and included 11 runners who completed the 40 km trail run and 12 runners who completed the 171 km ultra-trail. Blood samples were taken before and after the races.
Results:
Leukocyte concentrations significantly increased after both races. Circulating levels of IL-6, IL-1β, MCP-1, and IFN-γ were significantly higher after the longer race compared to the shorter race. Furthermore, while both races resulted in significant increases in IL-6 and IL-8, only the longer race resulted in significant increases in MIP-1β, IL-7, IL-17a, and IL-4.
Conclusions:
These results illustrate that a 171 km ultra-trail race results in greater modulations in cytokine profiles than a traditional trail race.

