title: Relationship between lower limbs kinematic variables and effectiveness of sprint during maximum velocity phase.
abstract: OBJECTIVE
  The aim of the study was to determine the relationships between time of running over a 15-25 m section of a 30-meter run along a straight line and changes in the angle and angular velocity observed in ankle, knee and hip joints. Therefore, the authors attempted to answer the question of whether a technique of lower limbs movement during the phase of sprint maximum velocity significantly correlates with the time of running over this section.
  
  
  METHODS
  A group of 14 young people from the Lower Silesia Voivodeship Team participated in the experiment. A Fusion Smart Speed System was employed for running time measurements. The kinematic data were recorded using Noraxon MyoMotion system.
  
  
  RESULTS
  There were observed statistically significant relationships between sprint time over a section from 15 to 25 m and left hip rotation (positive) and between this time and left and right ankle joint dorsi-plantar flexion (negative).
  
  
  CONCLUSIONS
  During the maximum velocity phase of a 30 m sprint, the effect of dorsi-plantar flexion performed in the whole range of motion was found to be beneficial. This can be attributed to the use of elastic energy released in the stride cycle. Further, hip rotation should be minimized, which makes the stride aligned more along a line of running (a straight line) instead of from side to side.
authors.affiliation: Department of Team Sport Games, University School of Physical Education, Wrocław, Poland.
authors.forename: Artur
authors.initials: A
authors.lastname: Struzik
authors.affiliation: Faculty of Health Sciences and Physical Education, Witelon State University of Applied Sciences in Legnica, Poland.
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Konieczny
authors.affiliation: University School of Physical Education, Wrocław, Poland.
authors.forename: Kamila
authors.initials: K
authors.lastname: Grzesik
authors.affiliation: University School of Physical Education, Wrocław, Poland.
authors.forename: Mateusz
authors.initials: M
authors.lastname: Stawarz
authors.affiliation: Department of Biomechanics, University School of Physical Education, Wrocław, Poland.
authors.forename: Sławomir
authors.initials: S
authors.lastname: Winiarski
authors.affiliation: Department of Team Sport Games, University School of Physical Education, Wrocław, Poland.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Rokita
mesh_terms: D000293:Adolescent; D054874:Athletic Performance / Q000502:physiology; D001696:Biomechanical Phenomena; D005684:Gait / Q000502:physiology; D006801:Humans; D035002:Lower Extremity / Q000502:physiology; D009068:Movement / Q000502:physiology; D016059:Range of Motion, Articular / Q000502:physiology; D012420:Running / Q000502:physiology*