title: Pro- and anti-inflammatory cytokine responses to a 164-km road cycle ride in a hot environment.
abstract: OBJECTIVE
  The purpose of this study was to examine the circulating cytokine response to a recreational 164-km road cycling event in a high ambient temperature and to determine if this response was affected by self-paced exercise time to completion.
  
  
  METHODS
  Thirty-five men and five women were divided into tertiles based on time to complete the cycling event: slowest (SLOW), moderate (MOD), and fastest (FAST) finishers. Plasma samples were obtained 1-2 h before (PRE) and immediately after (IP) the event. A high-sensitivity multiplex assay kit was used to determine the concentration of plasma anti-inflammatory cytokines (IL-4, IL-5, IL-10, IL-13) and pro-inflammatory cytokines (IL-1β, IL-2, IL-6, IL-7, IL-8, IL-12, GM-CSF, IFN-γ, and TNF-α).
  
  
  RESULTS
  The concentration of plasma IL-10 increased significantly (p < 0.05) in FAST and MOD groups and had no change in the SLOW group in response to a 164-km cycling event in the hot environment. Other cytokine responses were not influenced by the Time to completion. Pro-inflammatory cytokines IL-1β, IL-2, GM-CSF, and TNF-α decreased; whereas, IL-6 and IL-8 increased from PRE to IP. Additionally, anti-inflammatory cytokines IL-4 and IL-13 decreased.
  
  
  CONCLUSIONS
  Completion of a 164-km cycling event induced substantial changes in circulating pro- and anti-inflammatory cytokine concentrations. Time to completion appears to have a greater influence on the systemic IL-10 response than the environmental condition; however, it is possible that a threshold for absolute intensity must be reached for environmental conditions to affect the IL-10 response to exercise. Thus, cyclists from the FAST/MOD groups appear more likely to experience an acute transient immune suppression than cyclists from the SLOW group.
authors: Applied Physiology Laboratory, Department of Kinesiology, Health Promotion, and Recreation, University of North Texas, 1155 Union Circle #310769, Denton, TX, 76203-5017, USA.|Department of Biological Sciences, University of North Texas, 1155 Union Circle #305220, Denton, TX, 76203-5017, USA.
authors: Hui-Ying
authors: HY
authors: Luk
authors: Applied Physiology Laboratory, Department of Kinesiology, Health Promotion, and Recreation, University of North Texas, 1155 Union Circle #310769, Denton, TX, 76203-5017, USA.|Department of Biological Sciences, University of North Texas, 1155 Union Circle #305220, Denton, TX, 76203-5017, USA.
authors: Danielle E
authors: DE
authors: Levitt
authors: Human Performance Laboratory, Department of Kinesiology, University of Connecticut, Storrs, CT, 06269, USA.
authors: Elaine C
authors: EC
authors: Lee
authors: Human Performance Laboratory, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR, 72701, USA.
authors: Matthew S
authors: MS
authors: Ganio
authors: Human Performance Laboratory, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR, 72701, USA.
authors: Brendon P
authors: BP
authors: McDermott
authors: Department of Military and Emergency Medicine, Uniformed Services University of Health Sciences, Bethesda, MD, 20814, USA.
authors: Brian R
authors: BR
authors: Kupchak
authors: Applied Physiology Laboratory, Department of Kinesiology, Health Promotion, and Recreation, University of North Texas, 1155 Union Circle #310769, Denton, TX, 76203-5017, USA.|Department of Biological Sciences, University of North Texas, 1155 Union Circle #305220, Denton, TX, 76203-5017, USA.
authors: Brian K
authors: BK
authors: McFarlin
authors: Applied Physiology Laboratory, Department of Kinesiology, Health Promotion, and Recreation, University of North Texas, 1155 Union Circle #310769, Denton, TX, 76203-5017, USA.
authors: David W
authors: DW
authors: Hill
authors: Human Performance Laboratory, Department of Kinesiology, University of Connecticut, Storrs, CT, 06269, USA.
authors: Lawrence E
authors: LE
authors: Armstrong
authors: Applied Physiology Laboratory, Department of Kinesiology, Health Promotion, and Recreation, University of North Texas, 1155 Union Circle #310769, Denton, TX, 76203-5017, USA. Jakob.Vingren@unt.edu.|Department of Biological Sciences, University of North Texas, 1155 Union Circle #305220, Denton, TX, 76203-5017, USA. Jakob.Vingren@unt.edu.
authors: Jakob L
authors: JL
authors: Vingren
mesh_terms: D000893:Anti-Inflammatory Agents / Q000276:immunology*; D001642:Bicycling / Q000502:physiology*; D016207:Cytokines / Q000097:blood / Q000276:immunology*; D017753:Ecosystem; D005260:Female; D018869:Heat-Shock Response / Q000276:immunology*; D006358:Hot Temperature; D006801:Humans; D018836:Inflammation Mediators / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D010807:Physical Endurance / Q000502:physiology*; D005082:Physical Exertion
chemical_list: D000893:Anti-Inflammatory Agents; D016207:Cytokines; D018836:Inflammation Mediators
keywords: Anti-inflammatory cytokine; Exercise; Heat; Immune suppression; Pro-inflammatory cytokine; Ultra-endurance