title: Range of motion of body segments is larger during the maximal instep kick than during the submaximal kick in experienced football players.
abstract: BACKGROUND
  Football players with groin injury refrain from maximal kicking. Previous groin injury is related to decreased hip range of motion (ROM). Information on ROM differences between maximal and submaximal kicking within players is lacking. The first aim of this study is to quantify ROM of body segments during the maximal (MaxK) and submaximal (SubK) instep kick at four key points. The second aim is to study ROM differences of tension arc and movement trajectories between MaxK and SubK.
  
  
  METHODS
  Maximal (100% ball speed) and submaximal (70% ball speed) instep kicks from 15 experienced football players were registered with motion capture. ROM of hip, spine, pelvis and knee segments were determined at four key points. Differences in segmental ROM for the tension arc and movement trajectories between MaxK and SubK were studied. Effect sizes (ES) were calculated.
  
  
  RESULTS
  Ball speed was 98.8±9.0 km/h for MaxK and 69.5±7.1 km/h for SubK. Three key points timed similarly (P<0.05) for MaxK and SubK. MaxK shows increased ROM for all segments (P<0.05) but not for hip flexion. MaxK results in enlargement of tension arc and movement trajectories. Spine flexion (ES=3.2) and pelvis posterior tilt (ES=2.2) show the greatest relative increase.
  
  
  CONCLUSIONS
  Maximal kicking shows larger segmental ROM than submaximal kicking. Enlargement of tension arc and movement trajectories relate to increased segmental velocity, according to biomechanical concepts. Central body actions play an important role in kicking. This information can be used to further identify kicking strategies in athletes with injury.
authors.affiliation: Physiotherapy Institute Dukenburg, Nijmegen, The Netherlands - noor.rob@gmail.com.|Institute for Master Education in Musculoskeletal Therapies (SOMT), Amersfoort, The Netherlands - noor.rob@gmail.com.|Dutch Institute for Allied Health Care (NPi), Amersfoort, The Netherlands - noor.rob@gmail.com.
authors.forename: Rob
authors.initials: R
authors.lastname: Langhout
authors.affiliation: Dutch Institute for Allied Health Care (NPi), Amersfoort, The Netherlands.|Fysiotherapie Utrecht Oost B.V., Utrecht, The Netherlands.|Academic Medical Center, Department of Orthopedics and Sports Traumatology, Amsterdam, The Netherlands.|Academic Center for Evidence-based Sports Medicine (ACES), Amsterdam, The Netherlands.
authors.forename: Igor
authors.initials: I
authors.lastname: Tak
authors.affiliation: FysioStofberg, Maastricht, The Netherlands.
authors.forename: Roelof
authors.initials: R
authors.lastname: van der Westen
authors.affiliation: Maastricht University Medical Center, Department of Physical Therapy, Maastricht, The Netherlands.
authors.forename: Ton
authors.initials: T
authors.lastname: Lenssen
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D006801:Humans; D007091:Image Processing, Computer-Assisted; D035002:Lower Extremity / Q000502:physiology*; D008297:Male; D009068:Movement; D018482:Muscle, Skeletal / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology*; D012916:Soccer / Q000502:physiology*