title: Influence of resistance exercise on lumbar strength in older, overweight adults.
abstract: OBJECTIVE
  To measure lumbar extensor strength in overweight (OVW) and nonoverweight (NOVW) elderly adults before and after resistance exercise training (RX).
  
  
  METHODS
  Descriptive, comparative study.
  
  
  METHODS
  University-based wellness center and research facility.
  
  
  METHODS
  Eighty-four adults (age range, 60-83 y) were placed into 1 of 2 groups based on body mass index (BMI): control (NOVW; mean BMI, 22.5 kg/m(2)) or OVW (mean BMI, 29.2 kg/m(2)). Subjects were then randomly assigned to either a resistance exercise (RX) or nonexercising group.
  
  
  METHODS
  Six months of total body RX and isolated lumbar extension exercise.
  
  
  METHODS
  Body composition, isometric lumbar extension strength, and 1-repetition maximum for each of the training exercises.
  
  
  RESULTS
  Upper-body strength increased by 18.3% and 17.2% for the NOVW-RX and OVW-RX groups, respectively. Lower-body strength increased by 12.7% and 19.5% for the NOVW-RX and OVW-RX groups, respectively. At baseline, the OVW participants had greater total lumbar extension strength (1067 Nm vs 714 Nm) compared with the NOVW participants (P<.05). When expressed per kilogram of fat-free mass, there were no differences in baseline total lumbar extension strength. After RX, lumbar extension strength increased by 58% and 34% for the NOVW-RX and OVW-RX groups, respectively (P<.05). No changes in lumbar extension, upper- or lower-body strength were noted for the nontraining groups.
  
  
  CONCLUSIONS
  OVW subjects were found to have greater absolute and similar relative, upper-body, lower-body, and lumbar extension strength at baseline when compared with their NOVW counterparts. Also, isolated lumbar extension exercise was effective in improving lumbar extensor strength in OVW and NOVW persons.
authors.affiliation: Department of Physical Medicine and Rehabilitation, University of Virginia Health System, Charlottesville, VA, USA. kv8p@virginia.edu
authors.forename: Kevin R
authors.initials: KR
authors.lastname: Vincent
authors.forename: Randy W
authors.initials: RW
authors.lastname: Braith
authors.forename: Heather K
authors.initials: HK
authors.lastname: Vincent
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015444:Exercise; D005260:Female; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D008161:Lumbosacral Region; D008297:Male; D008875:Middle Aged; D018763:Muscle Fatigue / Q000502:physiology*; D018482:Muscle, Skeletal / Q000503:physiopathology*; D050177:Overweight / Q000502:physiology*; D014891:Weight Lifting