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338 Epidemiology of injury and illness among trail runners: a systematic review

Background Trail running (TR) is characterised by uneven varying running surfaces, with large elevation gains/losses. Therefore, the injury and illness profiles of TR may differ compared to road running. Limited information is available on injury and illness among trail runners (TRs) to help develop interventions towards injury prevention. Objective Systematically review data on TR injury and illness. Design Systematic review. Setting MEDLINE Ovid, PubMed, Scopus, SportsDiscus, CINAHL, Health Source: Nursing/Academic, Health Source: Consumer Ed. and Cochrane were searched from inception to February 2019. Methodological quality was assessed using an adapted Downs and Black assessment tool. Patients (or Participants) N/A (systematic review abstract). Interventions (or assessment of risk factors) Studies were included if they investigated injury and/or illness among TRs participating in training/racing and full-text available in English/French. Studies were excluded on biomarkers of injury/illness in the absence of participants reporting injury/illness, or if no clear evidence was found of investigating TR. Main outcome measurements TR injury (incidence, prevalence, anatomical site, tissue type, specific diagnosis, severity) and illness (incidence, prevalence, symptoms, specific diagnosis, body system, severity). Results Fourteen studies with 3094 participants were included. Six studies investigated injuries and illnesses, 3 studies investigated only injuries and 5 studies only illnesses. Twelve studies investigated race-related injury and/or illness and 2 studies included training-related injuries. Different study designs, injury and illness definitions, race distances, and surfaces, made pooling of results difficult. The foot, knee, ankle and thigh are the most common anatomical sites of TR injury, with lacerations/abrasions, blisters, muscle strains, cramping and ankle sprains most commonly diagnosed. TR illness involved the gastrointestinal tract (GIT), metabolic and cardiovascular body systems. Symptoms of nausea and vomiting related to GIT distress and dehydration are commonly reported. Conclusions Injury and illness are common among TRs participating in TR races. Limited evidence is available on training-related injury and illness in TR specific.