title: Influence of stride frequency and length on running mechanics: a systematic review.
abstract: BACKGROUND
  A high number of recreational runners sustain a running-related injury each year. To reduce injury risk, alterations in running form have been suggested. One simple strategy for running stride frequency or length has been commonly advocated.
  
  
  OBJECTIVE
  To characterize how running mechanics change when stride frequency and length are manipulated.
  
  
  METHODS
  In January 2012, a comprehensive search of PubMed, CINAHL Plus, SPORTDiscus, PEDro, and Cochrane was performed independently by 2 reviewers. A second search of the databases was repeated in June 2012 to ensure that no additional studies met the criteria after the initial search.
  
  
  METHODS
  Inclusion criteria for studies were an independent variable including manipulation of stride frequency or length at a constant speed with outcome measures of running kinematics or kinetics.
  
  
  METHODS
  Systematic review.
  
  
  METHODS
  Level 3.
  
  
  METHODS
  Two reviewers independently appraised each article using a modified version of the Quality Index, designed for assessing bias of nonrandomized studies.
  
  
  RESULTS
  Ten studies met the criteria for this review. There was consistent evidence that increased stride rate resulted in decreased center of mass vertical excursion, ground reaction force, shock attenuation, and energy absorbed at the hip, knee, and ankle joints. All but 1 study had a limited number of participants, with several methodological differences existing among studies (eg, overground and treadmill running, duration of test conditions). Although speed was held constant during testing, it was individually self-selected or fixed. Most studies used only male participants.
  
  
  CONCLUSIONS
  Despite procedural differences among studies, an increased stride rate (reduced stride length) appears to reduce the magnitude of several key biomechanical factors associated with running injuries.
authors.affiliation: Division of Sports Medicine, University of Wisconsin Hospital and Clinics, Madison, Wisconsin.
authors.forename: Amy G
authors.initials: AG
authors.lastname: Schubert
authors.affiliation: Division of Sports Medicine, University of Wisconsin Hospital and Clinics, Madison, Wisconsin.
authors.forename: Jenny
authors.initials: J
authors.lastname: Kempf
authors.affiliation: Department of Orthopedics and Rehabilitation, University of Wisconsin, Madison, Wisconsin.
authors.forename: Bryan C
authors.initials: BC
authors.lastname: Heiderscheit
keywords: cadence; step length; stride rate; systematic review