title: Influence of tibial shock feedback training on impact loading and running economy.
abstract: OBJECTIVE
  The purpose of this study was to determine whether real-time feedback (RTF) training would reduce impact loading variables previously linked with tibial stress fracture risk and whether these adaptations would influence running economy.
  
  
  METHODS
  Twenty-two male runners were randomly assigned to RTF (n = 12) and control (n = 10) groups. The RTF group received feedback based on their peak tibial axial accelerations (PTA) during six 20-min treadmill runs for 3 wk, whereas the control group adhered to the same training but without feedback. Unilateral three-dimensional kinematic and kinetic analysis and running economy measurements were conducted before, after, and at 1 month posttraining.
  
  
  RESULTS
  The RTF group had significant reductions (P < 0.01) in PTA and average and instantaneous vertical force loading rates after training as compared with no changes in the control group. These modifications in impact loads were only maintained in PTA 1 month after the training. A significant increase (P = 0.0033) in ankle plantarflexion at initial contact and a significant change (P = 0.030) in foot strike pattern from a rearfoot to midfoot strike pattern and a significant decrease (P = 0.008) in heel vertical velocity at initial contact appeared to be the primary mechanical strategies adopted by runners to reduce impact loading after RTF training. Despite these gait adaptations, running economy was unaffected.
  
  
  CONCLUSIONS
  The results of this study suggest that gait retraining using RTF is an effective means of eliciting reductions in impact loading without negatively affecting running economy. However, with loading rate reductions not being maintained 1 month posttraining, further research is required to determine how these reductions in impact severity can be retained long term.
authors.affiliation: 1Sport and Exercise Sciences Research Institute, University of Ulster, Newtownabbey, Co Antrim, NORTHERN IRELAND; 2Department of Health, Sport and Exercise Science, Waterford Institute of Technology, Waterford, IRELAND; 3School of Sport, Performing Arts and Leisure, University of Wolverhampton, Walsall, UNITED KINGDOM; and 4Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UNITED KINGDOM.
authors.forename: Adam Charles
authors.initials: AC
authors.lastname: Clansey
authors.forename: Michael
authors.initials: M
authors.lastname: Hanlon
authors.forename: Eric S
authors.initials: ES
authors.lastname: Wallace
authors.forename: Alan
authors.initials: A
authors.lastname: Nevill
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Lake
mesh_terms: D001696:Biomechanical Phenomena; D056228:Feedback, Sensory; D015775:Fractures, Stress / Q000517:prevention & control; D005684:Gait / Q000502:physiology*; D006801:Humans; D008297:Male; D010806:Physical Education and Training / Q000379:methods*; D012420:Running / Q000502:physiology*; D013977:Tibia / Q000293:injuries / Q000502:physiology*; D013978:Tibial Fractures / Q000517:prevention & control