title: The effects of preferred and non-preferred running strike patterns on tissue vibration properties.
abstract: OBJECTIVE
  To characterize soft tissue vibrations during running with a preferred and a non-preferred strike pattern in shoes and barefoot.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  Participants ran at 3.5 m s(-1) on a treadmill in shoes and barefoot using a rearfoot and a forefoot strike for each footwear condition. The preferred strike patterns for the subjects were a rearfoot strike and a forefoot strike for shod and barefoot running, respectively. Vibrations were recorded with an accelerometer overlying the belly of the medial gastrocnemius. Thirteen non-linearly scaled wavelets were used for the analysis. Damping was calculated as the overall decay of power in the acceleration signal post ground contact. A higher damping coefficient indicates higher damping capacities of the soft tissue.
  
  
  RESULTS
  The shod rearfoot strike showed a 93% lower damping coefficient than the shod forefoot strike (p<0.001). A lower damping coefficient indicates less damping of the vibrations. The barefoot forefoot strike showed a trend toward a lower damping coefficient compared to a barefoot rearfoot strike. Running barefoot with a forefoot strike resulted in a significantly lower damping coefficient than a forefoot strike when wearing shoes (p<0.001). The shod rearfoot strike showed lower damping compared to a barefoot rearfoot strike (p<0.001). While rearfoot striking showed lower vibration frequencies in shod and barefoot running, it did not consistently result in lower damping coefficients.
  
  
  CONCLUSIONS
  This study showed that the use of a preferred movement resulted in lower damping coefficients of running related soft tissue vibrations.
authors: Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada. Electronic address: henders@kin.ucalgary.ca.
authors: Hendrik
authors: H
authors: Enders
authors: Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada.
authors: Vinzenz
authors: V
authors: von Tscharner
authors: Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada.
authors: Benno M
authors: BM
authors: Nigg
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D005080:Exercise Test; D005545:Forefoot, Human; D005684:Gait / Q000502:physiology*; D006365:Heel; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology*; D012420:Running / Q000502:physiology*; D012775:Shoes; D014732:Vibration; D058067:Wavelet Analysis; D055815:Young Adult
keywords: Barefoot; Muscles; Running; Shoes; Strike pattern; Vibration