Whole-body-vibration, a popular exercise which uses a vibrating platform, is sometimes advertised as being able to boost bone density. However, a one-year-study on healthy postmenopausal women has shown that it has no such effect.
The study entitled, “Effects of 12 Months of Whole-Body Vibration (WBV) on Bone Density and Structure in Postmenopausal Women: A Randomized Controlled Trial”, is published in the November 15, 2011 issue of the Annals of Internal Medicine. This study was led by University Health Network (UHN) researchers, Drs. Angela Cheung, Shabbir Alibhai and Luba Slatkovska (lead author), who conducted this as part of her doctoral thesis.
“Although researchers are seeking alternatives to time-consuming exercise to improve bone density, the results of this study suggest this specific therapy is not effective in improving bone density,” said Dr. Angela Cheung, Director of the Osteoporosis Program at UHN, Director of the Centre of Excellence in Skeletal Health Assessment (CESHA), Lillian Love Chair in Women’s Health, and Associate Professor, University of Toronto. “Women would be farther ahead in making sure that they are exercising regularly and eating nutritious foods.”
About one in two women after the age of 50 will have a fracture in their lifetime that is related to osteoporosis. Osteoporosis is a condition that causes bones to become brittle and porous, decreasing bone strength and density, thereby increasing the risk of fracture or breakage. The most common sites of osteoporotic fracture are the wrist, spine and hip.
WBV involves standing on a motor-driven, oscillating small platform, like a bathroom scale, which produces upward accelerations from the feet to the weight-bearing muscles and bones, reproducing pressure on the bones, much like weight-bearing exercises are designed to do. With very little effort, participants can simply stand on these moving platforms to allegedly achieve the benefits of more labourious and intense exercises.
Participants in the study were 202 healthy postmenopausal women, with a mean age of 60, who were not on any prescription bone medications. They were randomized into three separate arms of the clinical trial which included low magnitude (which mimics muscle contractions in activities such as walking) at either 30Hz or 90 Hz oscillations. They were asked to stand on the platform for 20 minutes daily at home for 12 months.
The control group was asked not to use WBV therapies. All women were provided calcium and vitamin D supplements at baseline and six months, so that their daily intakes approximated 1200 mg and 1000 IU, respectively.
Whole body vibration has been recently proposed as an exercise intervention because of its potential for increasing force generating capacity in the lower limbs. Its recent popularity is due to the combined effects on the neuromuscular and neuroendocrine systems. Preliminary results seem to recommend vibration exercise as a therapeutic approach for sarcopenia and possibly osteoporosis. This review analyses state of the art whole body vibration exercise techniques, suggesting reasons why vibration may be an effective stimulus for human muscles and providing the rationale for future studies.
M Cardinale, J Wakeling
Br J Sports Med 2005;39:585–589. doi: 10.1136/bjsm.2005.016857
At baseline and 12 months, bone structure and bone density were measured at the hip, and lumbar spine, using dual-energy X-ray absorptiometry, and at the forearm and lower leg using high-resolution peripheral quantitative computed tomography (CT scan), the most advanced imaging technology for measuring bone structure and density. .
Twelve months of low-magnitude WBV at 90 and 30 Hz did not result in any significant changes in either bone density or bone structure in the participants as measured at the hip or lumbar spine, or lower leg or forearm, compared to those participants who did not do WBV.
The study concludes that low-magnitude WBV is not an effective therapy for the prevention of bone loss in postmenopausal women.
Instead, Dr. Cheung recommends that for women without osteoporosis, adequate calcium and vitamin D through diet and supplements, as well as weight-bearing exercises such as walking, dancing, or exercising with small weights, are better strategies for maintaining strong bones.
What is Whole Body Vibration?
Physiotherapists have been using short-term vibration in varying forms for many years. At low frequencies vibration can be used to relax muscles - indeed, in the past physiotherapists have put children with spasticity (high muscle tone) onto washing machines to help break the muscle spasm. Whilst at high frequencies physiotherapists use vibration to ‘wake up’ a muscle or to stimulate it.
Advances in technology have produced exciting new options in vibration therapy. Full size, standing platforms are now allowing whole body vibration strategies to produce more effective exercise programs.
Health Professionals, Gym Instructors and Personal Users are using vibration therapy to produce significant exercise benefits, including
Get up and go time
For more information about the Osteoporosis Program at University Health Network, please visit http://www.uhn.ca/osteoporosis, which includes information about the Osteoporosis Exercise Guide, demonstrating and explaining the most beneficial exercises in building bone strength and guidelines in preventing injuries and fractures.
A peer-reviewed grant from the Ontario Physicians’ Services Incorporated Foundation funded the study. Juvent Inc. supplied the WBV platforms, and Jamieson Laboratories provided calcium and vitamin D. None of these sources were involved in the study design, analysis or interpretation of data, or preparation of the manuscript.
Conclusion: Whole-body vibration therapy at 0.3g and 90 or 30 Hz for 12 months did not alter BMD or bone structure in postmenopausal women who received calcium and vitamin D supplementation.
Primary Funding Source: Physicians’ Services Incorporated Foundation.
About University Health Network
University Health Network consists of Toronto General, Toronto Western and Princess Margaret Hospitals, and Toronto Rehabilitation Institute. The scope of research and complexity of cases at University Health Network has made it a national and international source for discovery, education and patient care. It has the largest hospital-based research program in Canada, with major research in complex care, cardiology, transplantation, neurosciences, oncology, surgical innovation, infectious diseases, genomic medicine and rehabilitation medicine.
Lubomira Slatkovska, PhD;
Shabbir M.H. Alibhai, MD, MSc;
Joseph Beyene, PhD;
Hanxian Hu, MPH;
Alice Demaras, MSc; and
Angela M. Cheung, MD, PhD
Source: University Health Network (UHN)