Vibration Plate Frequency — Definition & Influences

The frequency of a vibration plate refers to how many times it moves up and down in one second. The unit of frequency is Hertz (Hz).

For example, if a vibration plate operates at 15 Hz, it means the platform completes 15 upward and downward movements per second.

Vibration Frequency Illustrated

Frequency of Linear Vibration

The animations below compare two linear vibration plates, one vibrates at 1Hz, the other vibrates at 4Hz.

Frequency = 1Hz Vibration plate move up-and-down 1 time in a second.	Frequency = 4Hz Vibration plate move up-and-down 4 time in a second.

These animations are slow motion for demonstration purpose. In reality, linear vibration plates usually vibrate at the frequency range between 15Hz and 40Hz.

Frequency of Pivotal Oscillation

The animations below compare two pivotal oscillation plates, one vibrates at 1Hz, the other vibrates at 3Hz.

Frequency = 1Hz Vibration plate move up-and-down 1 time in a second.	Frequency = 4Hz Vibration plate move up-and-down 3 time in a second.

These animations are slow motion for demonstration purpose. In reality, pivotal oscillation plates usually vibrate at the frequency range between 5Hz and 15Hz.

Frequency is a simple and accurate expression of how fast a vibration plate vibrates.

What is Speed Level?

Many manufacturers use speed level instead of frequency to represent the operating rate of their vibration plates. However, speed level is an arbitrary, model-specific measure defined by each manufacturer. It does not indicate the actual vibration frequency and may lead to misunderstanding.

Influences on Human Body

Vibration frequency is a key parameter of a vibration plate. Together with amplitude, they determine the vibration intensity and the pattern of stimulation applied to the user.

Natural Frequency & Resonance Effect

When vibration transfers from one object to another, if the vibration frequency of the source (vibration plate) matches the natural frequency of the target object (our body or tissues), the target object vibrates with maximum amplitude. This phenomenon is called resonance.

The natural frequency of an object is determined by the object's mass and rigidity. It is directly proportional to rigidity and inversely proportional to mass — meaning that heavier and more flexible objects have lower natural frequency, while lighter and more rigid objects have higher natural frequency.

Natural Frequencies of Body and Tissues

The natural frequencies of the human body and its tissues vary due to differences in weight, rigidity, structural flexibility, posture, and vibration direction.

Human Body The body as a whole is heavy and flexible, so it has a relatively low natural frequency. Studies suggest that the whole-body natural frequency typically lies between 5 Hz and 16 Hz, depending on body build, flexibility, posture, and vibration direction.

Tissue Tissues are lighter than the whole body, so that their natural frequencies are higher. Data are limited and vary among tissue types, but soft tissues typically resonate in the low tens of hertz, while stiffer tissues can reach into the hundreds of hertz. For example, eyeballs are small and soft, with a natural frequency of around 20 Hz, whereas bones are very rigid, exhibiting much higher frequencies—ranging from 200 Hz to 900 Hz, according to some studies.

Skeletal Muscle Skeletal muscle, a special type of soft tissue, has a variable natural frequency because its rigidity changes with contraction. When a muscle contracts, it becomes stiffer, raising its natural frequency. Muscle contraction therefore plays a crucial role in how the body responds to vibration stimulation. As a result, living skeletal muscles exhibit a wide range of natural frequencies, with studies indicating values from 10 Hz to 50 Hz.

Understanding the natural frequencies of the human body and its tissues helps explain how the body responds to vibration stimulation. The whole body resonates most strongly at frequencies between 5 Hz and 10 Hz, while muscle tissues respond more intensely within the 10 Hz to 40 Hz range.

Linear Vibration vs. Pivotal Oscillation - Influences of Frequency -

Linear vibration plates and pivotal oscillation plates are two distinct types of vibration machines. They differ not only in their movement patterns but also in their operating frequency ranges. As a result, the human body and its tissues respond differently to each type of vibration.

A linear vibration plate causes less overall body movement but more effectively works the skeletal muscles through inducing muscle contractions. In contrast, a pivotal oscillation plate produces greater whole-body motion with relatively less muscle activation.

Vibration Plate Model VT007 & VT009

Vibration plate models VT007 and VT000 are designed with a frequency range that aligns with the natural frequency of living skeletal muscles. This design maximizes vibration effectiveness by achieving optimized muscle stimulation through the resonance effect.