title: A randomized controlled trial of whole body vibration exposure on markers of bone turnover in postmenopausal women.
abstract: Purpose. To examine the effects of two doses of low-frequency (12 Hz), low-magnitude (0.3 g), whole body vibration on markers of bone formation and resorption in postmenopausal women. Methods. Women were recruited and randomized into a sham vibration control group, one time per week vibration group (1×/week), or three times per week vibration group (3×/week). Vibration exposure consisted of 20 minutes of intermittent vibration for the 1×/week and 3×/week groups, and sham vibration (<0.1 g) for the control group for eight weeks. Double-blinded primary outcome measures were urine markers of bone resorption: N-telopeptide X normalised to creatinine (NTx/Cr) and bone formation: bone-specific alkaline phosphatase (ALP). Results. Forty-six women (59.8 ± 6.2 years, median 7.3 years since menopause) were enrolled. NTx/Cr was significantly reduced (34.6%) in the 3×/wk vibration group but not in the 1×/wk vibration group compared with sham control (P < .01) group. No effect of time or group allocation was observed on the bone formation marker ALP (P = .27). Conclusion. We have shown for the first time that low-frequency, low-magnitude vibration 3×/week for eight weeks in postmenopausal women results in a significant reduction in NTx/Cr, a marker of bone resorption, when compared with sham vibration exposure.
authors.affiliation: Exercise, Health and Performance Faculty Research Group, Faculty of Health Sciences, The University of Sydney, Lidcombe, NSW 1825, Australia.
authors.forename: Sarah
authors.initials: S
authors.lastname: Turner
authors.forename: Margaret
authors.initials: M
authors.lastname: Torode
authors.forename: Mike
authors.initials: M
authors.lastname: Climstein
authors.forename: Geraldine
authors.initials: G
authors.lastname: Naughton
authors.forename: David
authors.initials: D
authors.lastname: Greene
authors.forename: Michael K
authors.initials: MK
authors.lastname: Baker
authors.forename: Maria A
authors.initials: MA
authors.lastname: Fiatarone Singh