title: Randomized controlled trial of the effects of a trunk stabilization program on trunk control and knee loading.
abstract: BACKGROUND
  Many athletic maneuvers involve coordination of movement between the lower and upper extremities, suggesting that better core muscle use may lead to improved athletic performance and reduced injury risk.
  
  
  OBJECTIVE
  To determine to what extent a training program with quasistatic trunk stabilization (TS) exercises would improve measures of core performance, leg strength, agility, and dynamic knee loading compared with a program incorporating only resistance training (RT).
  
  
  METHODS
  Thirty-seven male subjects were randomly assigned to either an RT-only or a resistance and TS training program, each lasting 6 wk. Core strength and endurance, trunk control, knee loading during unanticipated cutting, leg strength, and agility were collected pre- and posttraining.
  
  
  RESULTS
  Between-group analyses showed that the TS group significantly improved only core endurance when compared with the RT group (side bridge, P = 0.050). Within-group analyses showed that the TS group improved lateral core strength (maximum pull, cable on nondominant side; 44.5 ± 61.3 N, P = 0.037). Both groups increased leg strength (deadlift 1 repetition maximum; TS: 55.1 ± 46.5 lb, P = 0.003; RT: 33.4 ± 17.5 lb, P < 0.001) and decreased sagittal plane trunk control (sudden force release test; cable in front; TS: 2.54° ± 3.68°, P = 0.045; RT: 3.47° ± 2.83°, P = 0.004), but only the RT group decreased lateral trunk control (sudden force release; cable on dominant side; 1.36° ± 1.65°, P = 0.029). The RT group improved standing broad jump (73.2 ± 108.4 mm, P = 0.049) but also showed increased knee abduction moment during unanticipated cutting (1.503-fold increase (percentage body weight × height), P = 0.012).
  
  
  CONCLUSIONS
  Quasistatic TS exercises did not improve core strength, trunk control, or knee loading relative to RT potentially because of a lack of exercises, including unexpected perturbations and dynamic movement. Together, these results suggest the potential importance of targeted trunk control training to address these known anterior cruciate ligament injury risk factors.
authors.affiliation: Department of Orthopaedics, Ohio State University, Columbus, OH 43221, USA.
authors.forename: Steve T
authors.initials: ST
authors.lastname: Jamison
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: McNeilan
authors.forename: Gregory S
authors.initials: GS
authors.lastname: Young
authors.forename: Deborah L
authors.initials: DL
authors.lastname: Givens
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Best
authors.forename: Ajit M W
authors.initials: AM
authors.lastname: Chaudhari
mesh_terms: D000328:Adult; D006801:Humans; D007717:Knee / Q000502:physiology*; D007866:Leg / Q000502:physiology; D008297:Male; D053580:Muscle Strength / Q000502:physiology*; D010807:Physical Endurance / Q000502:physiology; D055070:Resistance Training / Q000379:methods*; D012420:Running / Q000502:physiology; D060726:Torso / Q000502:physiology*; D055815:Young Adult