3 Rules to remember
1. Any Vibration does not = Vibration Training
2. Light Vibration = Therapy
3. Heavy Vibration = Training
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Optimum Frequency for Training on Lineal Part 1
written by Jasper Sidhu
This topic is going to be split into two parts. The first part is from a Vibration Training Specialist who has been deeply involved in the industry for a number of years. Dr. Jasper Sidhu, DC
Vice President of Clinical Services, WAVE Manufacturing Inc.
Important note: These articles are written by experienced parties, with thousands of practical hours dealing with the public and vibration training. Both parties have also had stable platforms to use and stable companies to work from. Both parties also refused to inherit pre-conceptions as a base for their findings.
What’s the best frequency setting for my vibration machine?
Why do pivotal machines have a timer for 10 minutes while vertical machines sometimes max out at 2 minutes? A pivotal machine has 12 mm amplitude while vertical ones claim to be around 4 mm. Does that mean a pivotal is better? These are only some of the questions that people have when they are looking to buy a vibration machine, or when they’re looking for the right exercise program. This article focuses on answering the question ‘what’s the best frequency setting for my vibration machine?’
If you’ve ever lifted weights, or walked on a treadmill, you’ll know how important it is to get the right settings. Lifting weights requires the right amount of weight, lifted the right number of times for a certain period of time to see any benefits. Lifting weights that are too heavy, or too light, or lifting fast or lifting slow will affect how you’ll improve with your health and fitness. Treadmills also have different speeds, inclines and programs. Which would be the best for you? As you will see, vibration exercise is no different. One of the key factors of vibration training is the frequency of the platform. This is the number of times the platform drops up and down. The following key points outline the optimal frequency levels, taking into consideration research and practical field experience.
Frequencies are different on pivotal versus vertical machines
Vertical platforms typically go from 30 to 50 Hertz, while pivotal machines usually go from 5 to 30 Hertz. There are some machines on the market that go above or below this, but that’s the exception and not the rule. The difference in the frequencies is dependent on the nature of vibration. An oscillating, pivotal machine provides a different type of movement than a vertical unit. Hence, the frequencies will be different.
Research Findings on Frequency
Research findings vary widely with respect to optimal frequency. There are a few things to take into consideration. The results will vary depending on whether a vertical or pivotal machine was used, since each machine works in a different manner. Also, results vary depending on the expected outcomes of the study. Results vary depending on whether the study involved overall strength increase, power increase, recovery, circulation, or warm up.
Vibration and strength training
• Contrary to the 30 Hz frequency noted in some studies, others are seeing a trend towards 50 Hz. Two studies by Ronnestad BR (2009) reached this conclusion when assessing 1 RM in trained and untrained subjects. The findings showed significant improvements in countermovement jump, squat jump, and 1 RM strength at 50 Hz. Surprisingly, effects were not seen in 20 and 35 Hz. According to Ronnestad BR, if the purpose of using vibration is to increase the stimulus to the neuromuscular system to a greater extent than traditional explosive strength or power training, then 50 Hz is recommended. However, the author also noted that the exercises should be explosive in nature and submaximally loaded.
• Vibration has also been studied as an exercise tool before and in between strength training sets. Lamont HS et al (2009) has published several articles on this procedure. The frequency utilized in these studies have also been 50 Hz, with vibration used as a warm up, and utilized during the rest time in between sets of squats.
• Turner AP et al (2011) found 40 Hz to be the optimal frequency for increasing countermovement jump. The study focused on using an acute 30 second set of vertical vibration and its effect immediately on jump. It should be noted that the study compared 0, 30, 35 and 40 Hz for the study. It would have been highly recommended if the study incorporated 45 and 50 Hz as part of the study also, considering some studies are showing 50 Hz.
• A study by Adams J et al (2009) tested a vertical vibration machine across many frequencies, amplitudes and exercise and rest times. This was significant in that it looked for trends based on the frequencies and amplitude displacements. The study noted that increase power was noted at high frequencies and high displacements, or low frequencies and low displacements. This was one of the first studies to assess the relationship between frequency and displacement. Another study by Petit PD et al (2010) also verified one component of this study. They observed better muscle strength and power enhancement when higher frequency was combined with a higher amplitude displacement.
• One of the more interesting studies looked the effects of vibration on strength by placing study groups in a fixed vibration group versus an individualized vibration group. The fixed vibration group was tested at 30 Hz, while the individualized group was placed on a frequency that produced the greatest EMG activity. Giminiani RD et al (2008) found that the individualized group produced better strength and jump height gains than the group that was placed in a fixed vibration frequency program.
Practical Application of Vibration Frequencies
The research quoted in this paper is just a fraction of the research that is being published in this area of interest. However, our experience in implementing vibration training for our clients and patients has led to several key principles and findings that we follow:
• Research has largely been inconsistent with respect to finding the optimal frequency for vibration training. This is expected. It’s like trying to find the optimal weight load to use for increasing strength in weight training. It’s based on proper principles of overload. The amount of weight used can be different depending on whether you are looking to gain muscle, power, or speed. Some school of thought bases the decision on increasing the weight loads on a consistent basis. Increasing the overload on the muscles will make you stronger. Others promote periodization training, whereby the amount of exercise load is changed to prevent adaptation to the stimulus. Knowing this, it’s a disservice to hold vibration to a higher standard. That being said, there are several principles to follow with vibration exercise
• Vertical vibration machines seem to be effective for strength training between 30 and 50 Hz. Please note that we are talking about ‘strength training’ here. Now where do we get 30 to 50 Hz from? A study showed that the discharge rate of motor units during maximal effort reaches 30 to 50 impulses per second. Hence a vibration frequency of 30 to 50 Hz should elicit a pronounced stimulatory effect. One thing that is in common with all the research studies referenced is that the range of strength gains falls between 30 and 50 Hertz.
• One school of thought is starting off with a lower frequency and amplitude displacement and gradually building it up as the person becomes more comfortable or finds the exercises easier. This is based on the physiological overload principle. By increasing the frequency and amplitude gradually, it produces more acceleration and hence more ‘force’ on the body. This may be a good option for the deconditioned person that has not exercised in awhile.
• If a person is more fit, starting off at lower frequency and amplitude displacements will produce no effects. The person may become uninterested considering their goals of ‘harder effort’ will not be there. I’ve seen this many times with those that workout or are athletes. For these people, we quickly begin to adjust their frequencies based upon where they ‘feel’ they are feeling that it’s just right. Most of the time, increasing the frequency and / or amplitude displacement will lead to one range where that person feels they are getting a good muscle contraction effect from the vibration. One thing to note is that the person is not exercising ‘harder’, as they originally thought they should be. They believe they will be doing dynamic exercises with added weight loads since the vibration feels easy to them. However, by increasing the frequency and amplitude to their needs, they are often surprised that their muscles get fatigued so quickly, even being in a static posture. This concept is very similar to the research study by Giminiani RD et al (2008). What we’ve basically done is find the individualized frequency of that particular person and initiated vibration exercise at that specific frequency.
• We’ve also learned that the individual frequency usually ranges between 40 and 45 Hz. Again, this is just our own experience, just as some of the strength research only uses 50 Hz, and others use 30 Hz. However, we’ve also learned that this frequency can change after a few weeks of training. This is due to the body accommodating to the stimulus. In essence, the person gets uses to this frequency. This is similar to working out with the same weights for weeks on end. Therefore, the goal is always review that frequency and intensity level and adjust accordingly.
• We’ve also learned that the frequency is different for the upper and lower body. This may have more to do with positioning, use of straps or other accessories or the ability to add additional weight loads. Again, providing an individualized frequency may be more beneficial for the client.
• In summary, each individual has their own unique frequency that they are comfortable working out at. Someone that is deconditioned or undergoing a rehabilitation program may have to start on something with less force generation. This does not necessarily mean its’ the right frequency for them. It means that’s what they can handle. Once we get past this, we usually find a frequency of 40 to 45 Hz as being the ‘sweet spot’ for the majority of the people with ‘strength’ and ‘intense workout’ in their goals and needs.
Moras G et al. (2006) Electromyographic response during whole-body vibrations of different frequencies with progressive external loads (Internet); Feb. Buenos Aires (Argentina): Revista Digital; c1997-2006.
Turner AP et al. (2011) The acute effect of different frequencies of whole-body vibration on countermovement jump performance. J Strength Cond Res. Jun; 25(6): 1592-7.
Adams, J et al (2009) Optimal frequency, displacement, duration, and recovery patterns to maximize power output following acute whole-body vibration. Journal of Strength and Conditioning Research. 23(1); January; 237-245.
Petit PD et al (2010) Optimal whole body vibration settings for muscle strength and power enhancement in human knee extensors. J Electromyogr Kinesiol Dec; 20(6): 1186-95.
Di Giminiani R et al. (2009) The effects of vibration on explosive and reactive strength when applying individualized vibration frequencies. J Sports Sci Jan 15; 27(2): 169-77.
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