Physiological Effects of Soccer Heading
Condition: Repeated Head Impacts
Study type: Interventional

Summary: 
      There is growing concern for the resulting neurological and physiological outcomes from
      repeated head impacts in sports that do not manifest into traditional concussion symptoms.
      Specifically, there is evidence of immediate physiological deficits following controlled
      soccer heading. This study will compare the physiological changes of adolescents completing a
      set of soccer headers to those randomized to a set of soccer kicks to evaluate the effect of
      repetitive head impacts.
    

Detailed description: 
      There is limited data relating head impact biomechanics to neurological outcomes in humans.
      Concussion occurs from rotational loading of the head giving rise to diffuse stresses and
      strains in the brain tissue leading to autonomic and physiological dysfunction. Repeated head
      loading is common in contact sports and an integral part of soccer. It is unknown whether the
      same biomechanical forces from lower severity head impacts such as typical soccer heading
      cause temporary physiological deficits as well. Advancement of objective physiological
      function assessment devices allow measurement of neurological effects in the absence of
      diagnosed concussion. Recent soccer heading studies have evaluated neurophysiological changes
      pre- and post-repetitive heading. These studies have found conflicting results for the effect
      on neurocognitive performance immediately following a bout of heading, but consistent changes
      were observed in measures of vestibular balance, ocular function, and neurochemical
      biomarkers.

      Soccer heading biomechanics studies showed that females experienced higher severity head
      loading, and in equivalent sports such as soccer and basketball, females have higher
      concussion rates. This study will compare the physiological changes of male and female
      adolescents completing one of two soccer heading paradigms to those randomized to kicking to
      evaluate the effect of repetitive head impacts. This study will relate biomechanical measures
      of head loading with physiological function changes associated with repeated head impacts,
      and compare sex-differences in biomechanical measures and physiological changes.
    

Intervention name(s): Soccer Kicking; Soccer Heading (Frontal); Soccer Heading (Oblique)
Intervention type(s): Other; Other; Other
Intervention description(s): Subjects assigned to the soccer kicking arm will complete 10 soccer kicks in 10 minutes.; Subjects assigned to the soccer heading (frontal) arm will complete 10 frontal soccer headers (ball headed directly back to launch direction) in 10 minutes. Soccer balls will be projected at 10-17.5 m/s from approximately 10-15 m with a JUGS ball launcher.; Subjects assigned to the soccer heading (oblique) arm will complete 10 oblique soccer headers (ball headed 90° to the right from ball launch direction) in 10 minutes. Soccer balls will be projected at 10-17.5 m/s from approximately 10-15 m with a JUGS ball launcher.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Prevention
Keywords: Soccer Heading