Introduction
Whole Body vibration (WBV) has become a popular training method in recent years. This study investigated the effect of WBV on the length-tension relationship of the ankle dorsi (moving your ankle so that balls of feet raise) and plantarflexors ( moving your ankle in a way that raises the heal of your foot) as measured by a Biodex dynamometer (Biodex Medical Systems Inc, Shirley, NY).
Methods
Twenty healthy young adult males participated in this study and were exposed to two treatments. The first treatment (non-vibration) involved passive stretching of the plantarflexors at end range of motion for five 1-min bouts.
The second treatment involved the same passive stretch with superimposed WBV (frequency = 26 Hz) for five 1-min bouts on a rotary vibration plate (Galileo 900; Novotec, Pforzheim, Germany). Voluntary range of motion, peak torque, and corresponding joint angle of the plantar and dorsiflexors were recorded pre and post-treatment.
Within-treatment (before and after) and between-treatment (WBV and non-vibration) outcomes were assessed by repeated measures( Multivariate analysis of variance).
Results
No significant changes in the measures of ankle dorsiflexion were found within or between treatments. No significant changes in the measures of ankle plantarflexion were found after the non-vibration treatment. After WBV, however, there was a significant 7.1 degrees shift in the angle (P = 0.001) of peak plantarflexor torque production corresponding to a longer muscle length.
Conclusion
This study shows that stretched human ankle plantarflexors respond to WBV by generating peak voluntary torque at longer muscle lengths. This has possible benefits for the rehabilitation of patients with neuromuscular disorders (e.g., stroke) who experience short ankle flexor resting lengths.
Article Contributed by Josh with Hypergravity.
As an avid user of WBV, I am always looking to find legit research to back the benefits of its usage. Can you tell me what a “rotary platform” is (linear vs. pivotal)? Also, can you define “peak plantarflexor voluntary torque production”? As someone with an exercise phys. / therapy background, the term voluntary torque to describe plantarflexor muscle function is unfamiliar. This seems, yet again, like another study demonstrating relatively ambiguous results.
BTW-I really liked your article on Fat Burning. Very helpful and significantly helped me attach the two concepts (WBV & Fat Burning) together.
Thanks for posting the article Josh. This is the type of information that reinforces my view that vibration may have enormous benefits for the elderly, disabled, etc. for ADLs etc.
My understanding of torque as measured by the dynamometer would suggest that they were looking at the abilility to generate force throughout the motion of the ankle (dorsiflexion to plantarflexion…or from a flexed up position to a pointed down position of the foot). This should be a bell curve as the muscles generate less force at the extremes of there length (fully shortened or completely stretched out).
In this study, the force was seemingly better at the most stretched out positions of the ankle for both muscle groups with the wbv training group than the non-wbv group.
There cannot be too many ways to stretch the dorsi and plantar flexors on a platform. In my practice, using a linear platform, I will stretch the calf by hanging the heel off of the edge of the plate with the knee slightly unlocked or having the patient place one foot on a stepstool of equal height in front of the plate and essentially lunge onto the stepstool. As for the dorsiflexors in front of the shin (the “shin splint” muscles) you’d have to use one of these positions with the only difference being that the top of the foot is stretched out(passively pushed downward).
Is this study significant?…certainly when it comes to claims of the benefit of WBV on muscle force production. At the same time, it clearly does not support the benefits of WBV on muscle flexibility. Is this because it’s a pivotal platform vs a linear? Does Josh know he posted something supporting the benefits of a pivotal platform when he produces linear platforms?
Anybody taking WBV seriously could see through the ambiguities of this and other studies and I think we should question the accuracy and methods of the studies instead of saying things like “clearly this supports the benefits of it’s usage” I really wouldn’t call this “clear”
This is the only way it will ever get taken seriously and truly prove the value that we know it has.
I think you understand dorsiflexion/plantarflexion etc. Di. Your obeservation about how it was performed on a platform is a good one. I don’t know. Maybe Josh could fill us in? The outcome of greater torque at longer muscle lengths is what I found interesting.
Of course, you know Galileo oscillates Di. It says superimposed vibration in the article. How was it superimposed? I advised a company in 03 to get a broad patent to superimpose vibration on about any exercise device (cable, weight stack, etc.). The patent-pending went through in 05 and I was cut out of the picture.
Hi
Hope this is the right place to ask this but seeing the feet/ankles are being discussed here….
Would David’s practice of allowing his patients to hang the heel off the edge of the platform have any place alongside your bullet exercises?
The reason I ask is because I would like to know if there is any exercise to strengthen the foot arch that can be done with wbv and possibly eventually avoid the necessity for arch supports?
Just to update you, am now assisting another friend (the 4th)with back problems using your suggested exercises who was getting no joy with the physio and the results in just 4 days are absolutely amazing.
Regards
Keith
I have found that several of the positions on the bullet program have significantly assisted in the rehab of patients with “foot issues” relating to weakness of the foot intrinsics (muscles of the bottom of the foot). These muscles play a major role in the support of the arch. Having that been said, the degree of structural breakdown of the midfoot (joints, ligaments etc.) can be very difficult to correct without orthotics. Arch supports can be quite expensive and no one wants to rely on external supports throughout life, but they can be quite helpful and really help avoid problems “up the chain” (knees, hips, low back etc.)
FYI – The stretches I use for calf and plantar fascia flexibility would theoretically lengthen the tissue at the bottom of the foot and therefore reduce the strength of the arch.
No,I am not flat footed but I do get the odd cracking sound and the sensation of things moving around in the feet in the big toe/ball of the foot area now and again when walking.It’s difficult to assess but it does seem as if the arches are lower than they were say 20 years ago. I’ve played lots of sport over the years without problems but with the exception of regular wbv training am pretty sedentary now. I follow the Bullet program faithfully and I’ve seen my own physical improvement as well as what it does for back problems. Just wanted to know if there was any wbv viagra for the arches
Thank you both. The question was posed to see if there was a way to avoid future or looming foot problems or weaknesses. Can one assume there will be a gradual weakening of the foot structure over time without specific targetted or general exercising?
Its good to hear that the bullet exercises alone do work on the feet in a remedial as well as preventative way.
The answer differs from person to person as the degree of midfoot dysfunction can range from severe to mild. How old are you? I am assuming you are flat-footed? How severe?
Sounds like you are doing well overall…no real discomfort? Stick with the program and just keep monitoring your feet for noticeable changes. Arch supports can be quite helpful should you see things getting worse. WBV Viagra huh….maybe you just launched a new ad campaign
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Getting back to that study – what is the mechanism responsible for the increased force at a greater muscle length? Could it be “a disinhibiton of the disinhibiting” effect of the Golgi tendon organs(GTO)? Zatsiorsky and Kraemer mention this in their book Science and Practice of Strength Training about vibration. Often muscle spindles are mentioned as they are stretch receptors but what about the GTO which are force receptors? Also, how long does this increase in force last post vibration treatment? Is it a few minutes, an hour, etc? Researchers need to look at this more. It appears there is a post- activation potentiation with vibration from other studies – but how long does it last?
There’s an interesting study by Adams et al. in the Dec 08 JSCR showing power to be enhanced from 1-5 min post vibration treatment. The study looked at different combinations of frequencies, amplitudes, etc. Thus, according to this study, there is a post-activation potentiation (PAP) that last 1-5 min after vibration. The abstract can be read at http://www.nlm.nih.gov, click on PubMed, and type in vibration exercise as search terms. Any comments?
I look forward to your detailing of these codes and articles. That’s interesting what you said about not all vibration completing the effect and how the body isn’t easily tricked.
“Fitness efficacy of vibratory exercise compared to walking in postmenopausal women”
Another interesting study (link below). Definately futher support for vibration training/therapy on the older population. Look at the frequency though….wonder what results would look like if they were utilizing the 35-45 hz range.
http://www.ncbi.nlm.nih.gov/pubmed/19434420?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum
Yes, that’s another exciting study. The abstract didn’t mention which vibration platform they used. 12.6 Hz seems like a very low fq. I wonder why they used a fq this low?
After suffering from complete B12 depletion over a long time, resulting in lingering neuromuscular dysfunction, then spraining lumbar and thoracic areas of back due to weakness I now have chronic active trigger points up and down left side. Unfortunately stretching and strengthening those muscles (usual orthopedic protocol) without deactivating the trigger points has made pain worse.
Is there any evidence that WB therapy can help lessen trigger point activation? I have a good therapy/training WBV machine but now am not sure how to approach things. Any direction would be greatly appreciated.
b therapy can help?
Kris,
Trigger points represent local areas within the belly of a muscle that, as a result of stress or strain, have lost their local blood supply. This leads to poor oxygen supply, a build up of metabolic waste and the resulting pain and rigidity within the muscle.
There are no studies looking specifically at trigger point release and WBV as this is impossible to actually study. As a PT however, to treat TP’s, you use manual pressure or needling with the goal of improving blood supply. Improved blood supply and local circulation HAVE been studied and WBV has been shown to increase blood supply to the muscles.
The key is to be able to directly stimulate the muscle with TP’s. This makes the treatment, and the machine an important factor. Can you tell me where the TP’s are and which platform you have available to you?
My partner suffered a subarachnoid haemorrhage eighteen months ago. She can walk on her own now, but her balance needs improvement. She has just come home and I have bought equipment including a vibration machine to help with her home rehab. She is seeing a neurophysiotherapist weekly and of course I will ask her about her thoughts on how to use the machine. I’d appreciate your thouhts too though, on it’s use with respect to both balance and left side (particularly arm), reponsiveness.
Another effective way to target arm mobility in particular would be the use of a hand held vibration training tool such as a Flexi-Bar. As it is a hand held physiotherapeutic device, the vibrations transfer directly to the arm and shoulder. The lower frequency (4.6H) will allow for the reflexes and connective tissues to be targeted in particular and can be used to redevelop flexibility, mobility and strength..
The research on vibration and stroke or similar situations involving hemiparesis is lacking at the moment. Having that been said, there are some very positive studies involving spinal cord injury, MS and other neurological disorders. There is also quite a bit of research on balance and coordination of gait.
Based on this data and my own experience in the clinic with vibration therapy, I feel this will certainly help with the neuromuscular issues that your partner is struggling with. It is also an excellent adjunct to the work of the physio.
Having that been said, proper training requires that the appropriate platform system is being used and the program is sufficient for the nervousn system to adapt. The system should be a pivotal (side to side) system. There is a list of approved pivotal systems on this site.
Hope that helps.