As options for therapeutic technology grow, clinicians are expected to choose the most effective, economical and beneficial treatment regimens for their patients. Whole-body vibration (WBV) training and therapy may help answer these demands. The concept of WBV training was explored by Russian scientist Vladimir Nazarov to increase bone density and slow muscle atrophy during prolonged stays in space.

The technique reduced prolonged muscle atrophy through an involuntary response by stimulating mechanoreceptors (muscle spindles and golgi tendon organs) to contract when excited, and relax when facilitated. WBV exercises primarily rely on the involuntary stretch reflex of mechanoreceptors creating greater communication between the brain and contracting muscles. This concept is important during neuromuscular re-education because the increase in involuntary muscle response creates a jump-start effect on the muscle spindles.

WBV also activates voluntary muscle contractions, as evidenced by an increase in electromyogram activity. When mechanoreceptors in the muscle spindles are stimulated by vibration, messages are sent to the brain to produce a contract-relax response at the rate of current vibration. The response is called a tonic vibration reflex. The reflex amplifies the neuromuscular efficiency by stimulating 100 percent of muscle spindles at the same frequency of the vibration. The main factor that determines this biological effect is the frequency of vibration.

Positive Effects

Current research on WBV reveals promising results for increasing endocrine function, metabolic processes, and for neurological and orthopedic rehabilitation. Studies also confirm that its use has produced successful functional outcomes in people with a spinal cord injury (SCI), and improved postural stability and balance in Parkinson's disease (PD) patients.

WBV offers a low-impact exercise program that burns calories rapidly and increases cardiovascular fitness without the risk of pounding fragile or injured joints or bones. The cardiovascular system responds well to WBV by increasing cardiac output. The increase is due to the rapid contraction and relaxation of muscle spindles. This rapid exchange of blood supply works as a pump on the blood and lymphatic vessels, which improves the exchange of nutrients and toxins, and facilitates the healing process.

Even more compelling is the direct effect of WBV on the central nervous system (CNS). According to past and present research, the benefit of exercise to the brain is clearly documented and is responsible for enhancing memory and cognitive function. Research confirms that exercise increases spatial learning and memory in mice by employing a brain-derived neurotrophic factor (BDNF) to enhance cognitive function and synaptic plasticity, with possible increases in the release of neurotransmitters.^1,2BDNF also modulates synaptic plasticity and regulates axonal and dendritic branching and remodeling in the adult brain, giving rise to synaptogenesis in the arborizing of axon terminals, which assist in the efficacy of the synaptic transmission.¹

Aerobic exercise such as running can create exercise-induced formation of BDNF in the human hippocampus.^1-3sup> DNF is responsible for the survival, growth and maintenance of neurons during development.¹The proliferation, migration and differentiation of neurons is defined as neurogenesis.²

Consistent research supports that voluntary exercise increases neurogenesis in the adult hippocampus and improves spatial learning ability.⁴Neurogenesis is found only in the adult brain's olfactory bulb and hippocampus areas where learning and memory formation occurs, making a possible crossover effect in learning occur secondary to the location.^1,2,4Research in the 1970s led to numerous studies that concur with the belief that axons of neurons in the brain and spinal cord can regrow to some degree after trauma. This research has encouraged universities and rehabilitation centers across the world to study the effects of WBV in the CNS.

Benefits to SCI Patients

The Miami Project to Cure Paralysis at the University of Miami's Miller School of Medicine conducted a recent study that supports the fact that a change in motor learning and an increase in strength occur during WBV training in SCI populations. The main purpose of the study was to determine if repeated use of WBV would show improvements in gait function of SCI patients.

The study consisted of 17 subjects with chronic, motor-incomplete SCI. Gait function was assessed via 3-D motion capture before and after 12 sessions, three times a week for four weeks, with walking speed as a primary outcome measure. The results showed a statistically significant (p<0.001) improvement in walking speed. According to the study's final results, WBV may be useful to improve walking function, with effects that may persist for some time following the intervention.⁵

Benefits to PD Patients

Parkinson's disease is a motor system disorder marked by stiffness or rigidity, tremors, slowed movements, and balance and coordination issues. Two studies that support the theory of decreasing unwanted motor symptoms and improving postural stability in PD patients using WBV come from Johann Wolfgang Goethe University in Frankfurt, Germany.

The first study assessed the effects of random WBV on motor symptoms using the Unified Parkinson's Disease Rating Scale (UPDRS) in 68 people with PD. After a series of WBV treatment sessions, tremor and rigidity scores improved 24 to 25 percent.⁶The second study evaluated the effects of random WBV on postural control in 52 people with PD. The subjects were tested pre- and post-therapy using narrow standing and tandem standing. Following WBV training, spontaneous postural stability increased balance in the patients.⁷

Today, clinicians are using WBV to strengthen or fatigue muscles with unwanted muscle tone from abnormal CNS activity. Current research supports WBV for its positive biological effects, and some research suggests that motor learning can occur after WBV therapy. If patients can develop motor learning that's comparable to an hour of conventional resistance training after only 10 to 15 minutes on a vibrational plate, it stands to reason that WBV therapy should be regarded as a positive treatment option.

References

1. Vaynman, S., Ying, Z., & Gomez-Pinnilla, F. (2004). Hippocampal BDNF mediates the efficacy of exercise on synaptic plasticity and cognition. European Journal of Neuroscience, 20, 2580-2590.

2. Vaynman, S., Ying, Z., & Gomez-Pinnilla, F. (2003). Interplay between BDNF and signal transduction modulators in the regulation of the effects of exercise on synaptic-plasticity. Neuroscience, 122, 647-657.

3. Jordan, M.J., Norris, S.R., Smith, D.J., & Herzog, W. (2005). Vibration training: An overview of the area, training consequences, and future considerations. Journal of Strength and Conditioning Research, 19(2), 459-466.

4. Olson, A.K., Eadie, B.D., Ernst, C., & Christie, B.R. (2006). Environmental enrichment and voluntary exercise massively increase neurogenesis in the adult hippocampus via dissociable pathways. Hippocampus, 16(3), 250-260.

5. Ness, L.L., & Field-Fote, E.C. (2009). Whole-body vibration improves walking function in individuals with spinal cord injury: A pilot study. Gait Posture, 30(4), 436-440.

6. Haas, C.T., Turbanski, S., Kessler, K., & Schmidtbleicher, D. (2006). The effects of random whole-body-vibration on motor symptoms in Parkinson's disease. Neurorehabilitation, 21(1), 29-36.

7. Turbanski, S., Haas, C.T., Schmidtbleicher, D., Friedrich, A., & Duisberg, P. (2005). Effects of random whole-body vibration on postural control in Parkinson's disease. Research in Sports Medicine, 13(3), 243-256.

Pamela Mortemore is president of Body Kinetics of Florida Inc. in Fort Lauderdale.