title: [THE EFFECT OF A HAMSTRING STRECHING PROTOCOL ON HAMSTRING EXTENSIBIITY IN ADOLESCENT STUDENTS: INFLUENCE OF THE CLASS SESSION WEEKLY DISTRIBUTION].
abstract: BACKGROUND
  students who do hamstring stretching exercises, twice per week on alternate days, have showed significant increases on extensibility. Objetive: to compare the effects of a hamstring stretching program includes in the physical education classes in booth groups of adolescent, which had a different class session weekly distribution (non-consecutive sessions vs. consecutive sessions).
  
  
  METHODS
  fifty-eight adolescent students did a static-active stretching program on hamstring in the warm-up of both weekly physical education sessions for five weeks. The total duration of the stretching was five minutes. Students were divided in two groups: group A, with 30 students, had consecutive sessions (monday-tuesday), and the group B, with 29 students, had non-consecutive sessions (tuesday-friday). Hamstring extensibility was evaluated with the sit-and-reach test before (pre-test) and after (post-test) the intervention program.
  
  
  CONCLUSIONS
  there was found a significant increase in the sit-and-reach score in the group A (+2,15 cm) (p = 0.003) and in the group B (+2,31 cm) (p < 0.001). No significant differences were found between groups in the pre-test and the post-test (p > 0.05).
  
  
  CONCLUSIONS
  the implementation of an intervention program for five weeks, twice sessions a week, induded increases on hamstring extensibility in students. The class session weekly distribution does not affect the results.
authors: Facultad de Educación. Universidad de Murcia.. palopez@um.es.
authors: Álvaro
authors: Á
authors: Bohajar-Lax
authors: Cátedra de Traumatología del Deporte. Universidad Católica de Murcia, Murcia.. rvaquero@ucam.edu.
authors: Raquel
authors: R
authors: Vaquero-Cristóbal
authors: Departamento de Terapia Médico-Quirúrgica. Universidad de Extremadura, España.. palopez@um.es.
authors: Luis
authors: L
authors: Espejo-Antúnez
authors: Facultad de Educación. Universidad de Murcia.. palopez@um.es.
authors: Pedro Ángel
authors: PÁ
authors: López-Miñarro
mesh_terms: D000293:Adolescent; D000070633:Hamstring Muscles / Q000502:physiology*; D006801:Humans; D052580:Muscle Stretching Exercises; D010806:Physical Education and Training; D013334:Students