title: The NLstart2run study: Training-related factors associated with running-related injuries in novice runners.
abstract: OBJECTIVE
  The incidence of running-related injuries is high. Some risk factors for injury were identified in novice runners, however, not much is known about the effect of training factors on injury risk. Therefore, the purpose of this study was to examine the associations between training factors and running-related injuries in novice runners, taking the time varying nature of these training-related factors into account.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  1696 participants completed weekly diaries on running exposure and injuries during a 6-week running program for novice runners. Total running volume (min), frequency and mean intensity (Rate of Perceived Exertion) were calculated for the seven days prior to each training session. The association of these time-varying variables with injury was determined in an extended Cox regression analysis.
  
  
  RESULTS
  The results of the multivariable analysis showed that running with a higher intensity in the previous week was associated with a higher injury risk. Running frequency was not significantly associated with injury, however a trend towards running three times per week being more hazardous than two times could be observed. Finally, lower running volume was associated with a higher risk of sustaining an injury.
  
  
  CONCLUSIONS
  These results suggest that running more than 60min at a lower intensity is least injurious. This finding is contrary to our expectations and is presumably the result of other factors. Therefore, the findings should not be used plainly as a guideline for novices. More research is needed to establish the person-specific training patterns that are associated with injury.
authors.affiliation: Center for Sports Medicine, University of Groningen, University Medical Center Groningen, The Netherlands. Electronic address: b.kluitenberg@umcg.nl.
authors.forename: Bas
authors.initials: B
authors.lastname: Kluitenberg
authors.affiliation: Center for Sports Medicine, University of Groningen, University Medical Center Groningen, The Netherlands.
authors.forename: Henk
authors.initials: H
authors.lastname: van der Worp
authors.affiliation: Department of Rehabilitation, Nursing Science & Sports, Rudolf Magnus Institute of Neurosciences, University Medical Center Utrecht, The Netherlands.
authors.forename: Bionka M A
authors.initials: BM
authors.lastname: Huisstede
authors.affiliation: Departments of Epidemiology and Surgery, Research School CAPHRI, Maastricht University Medical Center+, Sports Medicine Center Maastricht, The Netherlands.
authors.forename: Fred
authors.initials: F
authors.lastname: Hartgens
authors.affiliation: Center for Sports Medicine, University of Groningen, University Medical Center Groningen, The Netherlands.
authors.forename: Ron
authors.initials: R
authors.lastname: Diercks
authors.affiliation: Department of Public and Occupational Health, EMGO+ Institute for Health and Care Research VU University Medical Center, Amsterdam, The Netherlands; Australian Centre for Research into Injury in Sport and its Prevention (ACRISP), Federation University Australia, SMB Campus, Australia.
authors.forename: Evert
authors.initials: E
authors.lastname: Verhagen
authors.affiliation: Department of General Practice, Erasmus MC University Medical Center Rotterdam, The Netherlands.
authors.forename: Marienke
authors.initials: M
authors.lastname: van Middelkoop
mesh_terms: D000328:Adult; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D005082:Physical Exertion / Q000502:physiology*; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D012420:Running / Q000293:injuries* / Q000706:statistics & numerical data; D011795:Surveys and Questionnaires; D013997:Time Factors
keywords: Etiology; Injury prevention; Novice runners; Running injuries