title: Effects of Long-Haul Transmeridian Travel on Subjective Jet-Lag and Self-Reported Sleep and Upper Respiratory Symptoms in Professional Rugby League Players.
abstract: OBJECTIVE
  To examine the effects of 24-h travel west across 11 time zones on subjective jet-lag and wellness responses together with self-reported sleep and upper respiratory symptoms in 18 professional rugby league players.
  
  
  METHODS
  Measures were obtained 1 or 2 d before (pretravel) and 2, 6, and 8 d after travel (post-2, post-6, and post-8) from Australia to the United Kingdom (UK) for the 2015 World Club Series.
  
  
  RESULTS
  Compared with pretravel, subjective jet-lag remained significantly elevated on post-8 (3.1 ± 2.3, P < .05, d > 0.90), although it was greatest on post-2 (4.1 ± 1.4). Self-reported sleep-onset times were significantly earlier on post-2 than at all other time points (P < .05, d > 0.90), and large effect sizes suggested that wake times were earlier on post-2 than on post-6 and post-8 (d > 0.90). Although significantly more upper respiratory symptoms were reported on post-6 than at pretravel (P < .05, d ˃ 0.90), no incidence of injury and negligible changes in wellness and muscle strength and range of motion (P > .05, d < 0.90) were evident after travel.
  
  
  CONCLUSIONS
  Results suggest that westward long-haul travel between Australia and the UK exacerbates subjective jet-lag and sleep responses, along with upper respiratory symptoms, in professional rugby league players. Of note, the increase in self-reported upper respiratory symptoms is a reminder that the demands of long-haul travel may be an additional concern in jet-lag for traveling athletes. However, due to the lack of sport-specific performance measures, it is still unclear whether international travel interferes with training to the extent that subsequent competition performance is impaired.
authors.forename: Peter M
authors.initials: PM
authors.lastname: Fowler
authors.forename: Rob
authors.initials: R
authors.lastname: Duffield
authors.forename: Donna
authors.initials: D
authors.lastname: Lu
authors.forename: Jeremy A
authors.initials: JA
authors.lastname: Hickmans
authors.forename: Tannath J
authors.initials: TJ
authors.lastname: Scott
mesh_terms: D001315:Australia; D005538:Football / Q000502:physiology*; D006801:Humans; D020179:Jet Lag Syndrome / Q000175:diagnosis*; D008297:Male; D053580:Muscle Strength / Q000502:physiology; D016059:Range of Motion, Articular; D012137:Respiratory System / Q000503:physiopathology*; D057566:Self Report; D012890:Sleep / Q000502:physiology*; D014195:Travel; D006113:United Kingdom; D055815:Young Adult
keywords: football; international travel; jet-lag syndrome; sleep patterns