title: Probiotic supplementation reduces the duration and incidence of infections but not severity in elite rugby union players.
abstract: OBJECTIVE
  The attenuation of the number and severity of infections is of importance to athletes. Probiotics use has increased over recent years with beneficial effects believed to include improvements in immune function. Research has focused on their effectiveness for reducing the number, duration and severity of infections amongst endurance athletes. At present no research has been undertaken with team sport athletes. This randomised controlled trial aimed to determine the effectiveness of probiotics on the number, duration and severity of infections amongst elite union rugby players.
  
  
  METHODS
  Randomised control trial with two arms; placebo and probiotic.
  
  
  METHODS
  Thirty elite rugby union players were allocated in random order to receive a probiotics supplement or a placebo for four weeks each. Supplements were consumed on a daily basis. There was a four week washout period between treatments. Participants completed a daily diary to identify and rate the severity of any infectious symptoms.
  
  
  RESULTS
  During the probiotic treatment 14/30 participants never experienced a single upper respiratory tract illness (URTI) or gastrointestinal (GI) episode, compared to 6/30 on the placebo supplementation (p=0.033). The mean±standard deviation for the number of days of illness tended to be higher for the placebo, (5.8±6.6 days) than probiotic (3.4±4.6 days), (p=0.054). There was no significant difference in the severity of the symptoms between the two treatment groups (p=0.110).
  
  
  CONCLUSIONS
  These positive effects of probiotic supplements provide evidence for the beneficial effects of daily supplementation with these probiotic strains in highly trained rugby union players.
authors.affiliation: Department of Human Nutrition, University of Otago, New Zealand.
authors.forename: Brylee A
authors.initials: BA
authors.lastname: Haywood
authors.affiliation: Department of Human Nutrition, University of Otago, New Zealand. Electronic address: katherine.black@otago.ac.nz.
authors.forename: Katherine E
authors.initials: KE
authors.lastname: Black
authors.affiliation: Chiefs Rugby Franchise, New Zealand.
authors.forename: Dane
authors.initials: D
authors.lastname: Baker
authors.affiliation: Chiefs Rugby Franchise, New Zealand.
authors.forename: James
authors.initials: J
authors.lastname: McGarvey
authors.affiliation: Chiefs Rugby Franchise, New Zealand.
authors.forename: Phil
authors.initials: P
authors.lastname: Healey
authors.affiliation: Department of Human Nutrition, University of Otago, New Zealand.
authors.forename: Rachel C
authors.initials: RC
authors.lastname: Brown
mesh_terms: D000328:Adult; D018592:Cross-Over Studies; D019587:Dietary Supplements; D005538:Football; D005767:Gastrointestinal Diseases / Q000382:microbiology / Q000517:prevention & control*; D006801:Humans; D008297:Male; D019936:Probiotics / Q000627:therapeutic use*; D012141:Respiratory Tract Infections / Q000517:prevention & control*; D012720:Severity of Illness Index; D016037:Single-Blind Method; D013997:Time Factors; D055815:Young Adult
keywords: Supplements; Team sports; Training; Upper respiratory tract