title: Comparison of gluteal and hamstring activation during five commonly used plyometric exercises.
abstract: BACKGROUND
  Anterior cruciate ligament injuries occur frequently in athletics, and anterior cruciate ligament injury prevention programs may decrease injury risk. However, previous prevention programs that include plyometrics use a variety of exercises with little justification of exercise inclusion. Because gluteal and hamstring activation is thought to be important for preventing knee injuries, the purpose of this study was to determine which commonly used plyometric exercises produce the greatest activation of the gluteals and hamstrings.
  
  
  METHODS
  EMG (Electromyography) amplitudes of the hamstring and gluteal muscles during preparatory and loading phases of landing were recorded in 41 subjects during 5 commonly used plyometric exercises. Repeated measures ANOVAs (Analysis of Variance) were used on 36 subjects to examine differences in muscle activation.
  
  
  RESULTS
  Differences in hamstring (P<.01) and gluteal (P<.01) activities were identified across exercises during the preparatory and landing phases. The single-leg sagittal plane hurdle hops produced the greatest gluteal and hamstring activity in both phases. The 180° jumps did not produce significantly greater gluteal or hamstring activity than any other exercise.
  
  
  CONCLUSIONS
  Single-leg sagittal plane hurdle hops may be the most effective exercise to activate the gluteals and hamstrings and may be important to include in anterior cruciate ligament injury prevention programs, given the importance of these muscles for limiting valgus loading of the knee. Because 180° jumps do not produce greater gluteal and hamstring activation than other plyometric exercises, their removal from injury prevention programs may be warranted without affecting program efficacy.
authors.affiliation: Human Performance Laboratory, Department of Kinesiology and Applied Physiology, University of Delaware, Newark, DE, USA. Electronic address: astrum@udel.edu.
authors.forename: Aaron H
authors.initials: AH
authors.lastname: Struminger
authors.forename: Michael D
authors.initials: MD
authors.lastname: Lewek
authors.forename: Shiho
authors.initials: S
authors.lastname: Goto
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Hibberd
authors.forename: J Troy
authors.initials: JT
authors.lastname: Blackburn
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D004576:Electromyography; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D007718:Knee Injuries / Q000517:prevention & control; D007719:Knee Joint / Q000502:physiology; D007866:Leg / Q000502:physiology; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology*; D059385:Plyometric Exercise; D012016:Reference Values; D013848:Thigh / Q000502:physiology; D055815:Young Adult
keywords: Anterior cruciate ligament; Electromyography; Gluteus maximus; Gluteus medius; Hamstrings; Plyometric exercise