Purpose: 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.
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
Address for Correspondence: Adam Charles Clansey, Ph.D., Sport and Exercise Sciences Research Institute, University of Ulster, Jordanstown, Shore Rd, Co Antrim, BT37 0QB, Northern Ireland; E-mail: firstname.lastname@example.org.
Submitted for publication June 2013.
Accepted for publication September 2013.