title: Acute effect of whole-body vibration at optimal frequency on muscle power output of the lower limbs in older women.
abstract: OBJECTIVE
  The aim of this study was to identify the frequency of whole-body vibration (WBV) that elicits the greatest improvement in lower limb power output after an acute exposure in older women, with the hypothesis that an individualized optimal vibration frequency (OVF) would be more effective than a fixed vibration frequency.
  
  
  METHODS
  Maximal power output was measured during a double leg press on an isoinertial dynamometer in nine women with a mean (SD) age of 71 (3) yrs, 1 and 5 mins after WBV on a platform at three different frequencies, in a random order: 20 Hz, 50 Hz, and OVF, determined for each subject by identifying the frequency corresponding to the maximal electromyographic muscle response.
  
  
  RESULTS
  The mean (SD) OVF was 33 (2.5) Hz. The 25.9% increase in maximal power output after 1 min of WBV at OVF was significantly higher (P < 0.05) than the 14.3% increase after 1 min of WBV at 20 Hz. Similarly, the 32.1% increase in maximal power output after 5 mins of WBV at OVF was significantly higher (P < 0.01) than the 16.1% and 16.3% increase after 5 mins of WBV at 20 Hz and 50 Hz, respectively.
  
  
  CONCLUSIONS
  Frequency of WBV should be prescribed in an individualized fashion, within the range of 30-35 Hz in this target population of older women.
authors.affiliation: Department of Medicine and Health Sciences, University of Molise, Campobasso, Italy.
authors.forename: Arrigo
authors.initials: A
authors.lastname: Giombini
authors.forename: Andrea
authors.initials: A
authors.lastname: Macaluso
authors.forename: Luca
authors.initials: L
authors.lastname: Laudani
authors.forename: Annalisa
authors.initials: A
authors.lastname: Di Cesare
authors.forename: Alberto
authors.initials: A
authors.lastname: Piccinini
authors.forename: Fabio
authors.initials: F
authors.lastname: Pigozzi
authors.forename: Vincenzo Maria
authors.initials: VM
authors.lastname: Saraceni
mesh_terms: D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology; D005260:Female; D006801:Humans; D035002:Lower Extremity / Q000502:physiology; D009119:Muscle Contraction / Q000502:physiology*; D053580:Muscle Strength / Q000502:physiology*; D010809:Physical Fitness / Q000502:physiology*; D055070:Resistance Training; D012494:Sampling Studies; D012680:Sensitivity and Specificity; D014732:Vibration / Q000627:therapeutic use*