title: EMG evaluation of hip adduction exercises for soccer players: implications for exercise selection in prevention and treatment of groin injuries.
abstract: BACKGROUND
  Exercise programmes are used in the prevention and treatment of adductor-related groin injuries in soccer; however, there is a lack of knowledge concerning the intensity of frequently used exercises.
  
  
  OBJECTIVE
  Primarily to investigate muscle activity of adductor longus during six traditional and two new hip adduction exercises. Additionally, to analyse muscle activation of gluteals and abdominals.
  
  
  METHODS
  40 healthy male elite soccer players, training >5 h a week, participated in the study. Muscle activity using surface electromyography (sEMG) was measured bilaterally for the adductor longus during eight hip adduction strengthening exercises and peak EMG was normalised (nEMG) using an isometric maximal voluntary contraction (MVC) as reference. Furthermore, muscle activation of the gluteus medius, rectus abdominis and the external abdominal obliques was analysed during the exercises.
  
  
  RESULTS
  There were large differences in peak nEMG of the adductor longus between the exercises, with values ranging from 14% to 108% nEMG (p<0.0001). There was a significant difference between legs in three of the eight exercises (35-48%, p<0.0001). The peak nEMG results for the gluteals and the abdominals showed relatively low values (5-48% nEMG, p<0.001).
  
  
  CONCLUSIONS
  Specific hip adduction exercises can be graded by exercise intensity providing athletes and therapists with the knowledge to select appropriate exercises during different phases of prevention and treatment of groin injuries. The Copenhagen Adduction and the hip adduction with an elastic band are dynamic high-intensity exercises, which can easily be performed at any training facility and could therefore be relevant to include in future prevention and treatment programmes.
authors.affiliation: Arthroscopic Centre Amager, Copenhagen University Hospital, Copenhagen, Denmark Aspetar Sports Groin Pain Centre, Aspetar, Qatar Orthopaedic and Sports Medicine Hospital, Doha, Qatar.
authors.forename: Andreas
authors.initials: A
authors.lastname: Serner
authors.affiliation: National Research Centre for the Working Environment, Copenhagen, Denmark.
authors.forename: Markus Due
authors.initials: MD
authors.lastname: Jakobsen
authors.affiliation: National Research Centre for the Working Environment, Copenhagen, Denmark.
authors.forename: Lars Louis
authors.initials: LL
authors.lastname: Andersen
authors.affiliation: Arthroscopic Centre Amager, Copenhagen University Hospital, Copenhagen, Denmark Aspetar Sports Groin Pain Centre, Aspetar, Qatar Orthopaedic and Sports Medicine Hospital, Doha, Qatar.
authors.forename: Per
authors.initials: P
authors.lastname: Hölmich
authors.affiliation: National Research Centre for the Working Environment, Copenhagen, Denmark.
authors.forename: Emil
authors.initials: E
authors.lastname: Sundstrup
authors.affiliation: Arthroscopic Centre Amager, Copenhagen University Hospital, Copenhagen, Denmark.
authors.forename: Kristian
authors.initials: K
authors.lastname: Thorborg
mesh_terms: D001265:Athletic Injuries / Q000517:prevention & control; D004566:Electrodes; D004576:Electromyography / Q000379:methods; D005081:Exercise Therapy / Q000379:methods*; D006119:Groin / Q000293:injuries*; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D007866:Leg; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology; D011187:Posture / Q000502:physiology; D012916:Soccer / Q000293:injuries*; D055815:Young Adult
keywords: Exercise; Groin injuries; Injury Prevention; Physiotherapy; Soccer