Abstract
Introduction
A large running population combined with high injury rates has developed a need for proactive methods to reduce injury risk. Gait-retraining (GR) interventions using stride length (SL) manipulation have shown success in reducing lower-limb loading (Barton et al., 2016), particularly for the vertical ground reaction force impact peak (GRF). A case study was used to highlight individual responses to GR (Davis, 2005) with the aim to assess the impact of a four-week intervention on SL reduction and subsequent biomechanical changes in two habitual runners.
Methods
Two habitual runners experiencing knee pain, completed eight GR sessions aiming to reduce SL by 2-4% (Moore, 2016) over a four-week period. Biomechanical measures and knee pain were initially assessed and were compared to results obtained in post- intervention. Verbal, auditory and visual feedback regarding SL was provided during the first four GR sessions before verbal and auditory feedback were removed for sessions five to eight. For the discrete measures percentage differences were determined between data sets pre and post intervention and Hedge’s g reported the effect size. One-dimensional statistical parametric mapping (1D-SPM) was used to assess significant differences in the vertical and horizontal GRF throughout stance between pre- and post-testing (Pataky, 2012).
Results
Participant 1 (P1) achieved SL reduction of 2.6% resulting in substantial reductions in the majority of loading measures, including a 9% reduction in vertical GRF impact peak (p<0.001 via 1D-SPM) and knee pain was reduced by 24.5%. Participant 2 (P2) did not achieve the required SL reduction, achieving a 1.3% reduction, which lead to increases in loading measures (vertical GRF impact peak by 1.9%) and knee pain (by 28.6%) following GR.
Discussion
A reduction of SL, within the desired range, produced positive changes regarding lower-limb loading and knee pain (Barton et al., 2016). However, a SL reduction of only 1.3% produced notably different results as loading variables and knee pain increased following GR. Opposite responses between P1 and P2 were seen in biomechanical loading measures (Heiderscheit et al., 2011) which suggested that P2 needed to continue with GR until the desired reduction in SL had been achieved. The highlighted individual responses of habitual runners to GR, endorses a more individual approach to injury prevention training.
References
Barton C, Bonanno D, Carr J, Neal B, Malliaras P, Franklyn-Miller A, Menz H. (2016). Br J Sports Med, 50, 513-526
Davis, I (2005). Orthopaedic Physical Therapy practice, 17(2), 8.
Heiderscheit B, Chumanov E, Michalski M, Wille C, Ryan M. (2011). Med Sci Sports Exerc, 43(2), 296
Moore I. (2016). Sports Medicine, 1-15.
Pataky T. (2012). Comput Method Biomec, 15(3):295–301.
Original language | English |
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Title of host publication | Congress of European Colleges of Sport Science |
Publication status | Published - Jun 2017 |