title: Irisin in response to acute and chronic whole-body vibration exercise in humans.
abstract: OBJECTIVE
  Irisin is a recently identified myokine, suggested to mediate the beneficial effects of exercise by inducing browning of white adipocytes and thus increasing energy expenditure. In humans, the regulation of irisin by exercise is not completely understood. We investigated the effect of acute and chronic whole-body vibration exercise, a moderate-intensity exercise that resembles shivering, on circulating irisin levels in young healthy subjects.
  
  
  METHODS
  Healthy untrained females participated in a 6-week program of whole-body vibration exercise training. Blood was drawn before and immediately after an acute bout of exercise at baseline (week 0) and after 6 weeks of training.
  
  
  RESULTS
  The resting irisin levels were not different at baseline (week 0) and after 6 weeks of training. At both 0 and 6 weeks of training, an acute bout of vibration exercise significantly elevated circulating irisin levels by 9.5% and 18.1%, respectively (p=0.05 for the percent change of irisin levels).
  
  
  CONCLUSIONS
  Acute bouts of whole-body vibration exercise are effective in increasing circulating irisin levels but chronic training does not change levels of baseline irisin levels in humans.
authors.affiliation: Section of Endocrinology, Boston VA Healthcare System, Harvard Medical School, Boston, MA. Electronic address: jhuh@bidmc.harvard.edu.
authors.forename: Joo Young
authors.initials: JY
authors.lastname: Huh
authors.affiliation: School of Physical Education and Sports Science, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors.forename: Vassilis
authors.initials: V
authors.lastname: Mougios
authors.affiliation: School of Physical Education and Sports Science, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors.forename: Athanasios
authors.initials: A
authors.lastname: Skraparlis
authors.affiliation: School of Physical Education and Sports Science, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors.forename: Athanasios
authors.initials: A
authors.lastname: Kabasakalis
authors.affiliation: Section of Endocrinology, Boston VA Healthcare System, Harvard Medical School, Boston, MA.
authors.forename: Christos S
authors.initials: CS
authors.lastname: Mantzoros
mesh_terms: D000328:Adult; D004797:Enzyme-Linked Immunosorbent Assay; D015444:Exercise; D005260:Female; D005353:Fibronectins / Q000097:blood* / Q000378:metabolism; D006801:Humans; D007537:Isometric Contraction; D018482:Muscle, Skeletal / Q000378:metabolism / Q000502:physiology*; D012768:Shivering; D013997:Time Factors; D015854:Up-Regulation; D014732:Vibration; D055815:Young Adult
chemical_list: C577593:FNDC5 protein, human; D005353:Fibronectins
keywords: FNDC5; Irisin; Myokine; Whole body vibration exercise