title: Effects of training frequency on lumbar extension strength in patients recovering from lumbar dyscectomy.
abstract: OBJECTIVE
  To determine the effects of lumbar extension exercise on strength, disability index, and pain scores in patients after lumbar discectomy surgery.
  
  
  METHODS
  Prospective comparative study.
  
  
  METHODS
  Forty patients experiencing a herniated disc at lumbar levels were divided into 4 subgroups for different training frequencies: twice/week (group 1), once/week (group 2), once/2 weeks (group 3), and no training (control).
  
  
  METHODS
  After completing the initial 12-week training, all subjects participated in a 12-week follow-up training.
  
  
  RESULTS
  Groups 1 and 2 showed significant increases in lumbar extension strength (26 Nm and 7 Nm, respectively), while group 3 and the control group showed significant decreases in lumbar extension strength. Groups 1 and 2 showed significant decreases in disability index (1.4 and 0.8 Oswestry Disability Index points, respectively), and group 1 showed significant decreases in back and leg pain scores (both 0.5 units on a 10-cm visual analog scale).
  
  
  CONCLUSIONS
  Lumbar extension strength and disability index improve with training frequencies of once and twice per week, while back and leg pain improve with a training frequency of twice per week. The clinical importance of these improvements is questionable, as the scores were already very low after the discectomy and the magnitude of absolute improvements were small.
authors.affiliation: Department of Kinesiology, University of Maryland, College Park, MD 20742, USA.
authors.forename: You-Sin
authors.initials: YS
authors.lastname: Kim
authors.forename: Jaebum
authors.initials: J
authors.lastname: Park
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Hsu
authors.forename: Kyu Kwon
authors.initials: KK
authors.lastname: Cho
authors.forename: Yoon Hyuk
authors.initials: YH
authors.lastname: Kim
authors.forename: Jae Kun
authors.initials: JK
authors.lastname: Shim
mesh_terms: D000328:Adult; D004185:Disability Evaluation; D017586:Diskectomy / Q000009:adverse effects / Q000534:rehabilitation*; D005500:Follow-Up Studies; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000534:rehabilitation* / Q000601:surgery; D007537:Isometric Contraction; D008159:Lumbar Vertebrae / Q000503:physiopathology; D053580:Muscle Strength / Q000502:physiology; D010147:Pain Measurement; D011446:Prospective Studies; D020127:Recovery of Function; D055070:Resistance Training; D013997:Time Factors; D016896:Treatment Outcome