title: Irisin in response to exercise in humans with and without metabolic syndrome.
abstract: BACKGROUND
  Irisin is a recently identified exercise-induced myokine. However, the circulating levels of irisin in response to different types of exercise in subjects with metabolic syndrome are unknown.
  
  
  OBJECTIVE
  This study aimed to study the levels of irisin in healthy males and subjects with metabolic syndrome at baseline and in response to exercise.
  
  
  METHODS
  Each individual completed high-intensity interval exercise (HIIE), continuous moderate-intensity exercise (CME), and resistance exercise (RE) sessions in a random, crossover design. Percentage change in circulating irisin levels was examined. Two different irisin assays were used to compare the results of the RE study.
  
  
  RESULTS
  Circulating irisin increased immediately after HIIE, CME, and RE and declined 1 hour later. The increase was greater in response to resistance compared with either high-intensity intermittent exercise or CME. Change in irisin in response to exercise did not differ between individuals with and without metabolic syndrome.
  
  
  CONCLUSIONS
  Exercise is able to increase circulating irisin levels in individuals with the metabolic syndrome as well as healthy individuals. Whether this increase may contribute to the beneficial effects of exercise on patients with the metabolic syndrome remains to be studied further.
authors.affiliation: Division of Endocrinology, Diabetes, and Metabolism (J.Y.H., K.H.P., C.S.M.), Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215; School of Physical Education and Sports Science (A.S., V.M.), Aristotle University of Thessaloniki, Thessaloniki 54124, Greece; Department of Family Medicine (K.H.P.), Hallym University Sacred Heart Hospital, Hallym University, Gyeonggi-do 431-796, Korea; and Section of Endocrinology (C.S.M.), Boston VA Healthcare System, Harvard Medical School, Boston, Massachusetts 02130.
authors.forename: Joo Young
authors.initials: JY
authors.lastname: Huh
authors.forename: Aikaterina
authors.initials: A
authors.lastname: Siopi
authors.forename: Vassilis
authors.initials: V
authors.lastname: Mougios
authors.forename: Kyung Hee
authors.initials: KH
authors.lastname: Park
authors.forename: Christos S
authors.initials: CS
authors.lastname: Mantzoros
mesh_terms: D000328:Adult; D018592:Cross-Over Studies; D015444:Exercise / Q000502:physiology*; D005353:Fibronectins / Q000097:blood*; D006801:Humans; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood*; D008875:Middle Aged; D010807:Physical Endurance / Q000502:physiology; D055070:Resistance Training; D012420:Running / Q000502:physiology; D016138:Walking / Q000502:physiology
chemical_list: C577593:FNDC5 protein, human; D005353:Fibronectins