There are a variety of elements that make up the technical specs of each PEMF system. The most widely-discussed and studied are frequency and intensity, but waveform, coil configuration, and application area are also discussed with some regularity. Knowing which parameters are most likely to impact your health concerns is important in helping you compare similar systems to one another.
shutterstock_1720850-time-varied-field-sA frequency range is always an important aspect of a PEMF system. Some systems produce a single frequency, some produce frequencies within a small range, some have a huge range of optional frequencies.
Most full-body PEMF systems have at least a frequency range that mimics that of the brain – roughly between 1 and 30Hz. These frequencies are sometimes referred to as “earth-based” frequencies, which is somewhat of a misnomer since there is a vast array of frequencies present in our atmosphere.
But, for every system that produces only brainwave frequencies, there is a system that produces much, much higher frequencies – some into the kHz range. Both high and low frequencies have been studied extensively, and each range has its place therapeutically.
The body itself produces a vast array of frequencies – different cell types, organ systems, and pathologies all communicate in different ways, creating their own biological windows that create or respond to unique frequencies.
While a wide variety of frequencies have been studied individually, very littler comparative work has been done. So while one study may find that a specific frequency is great for arthritis pain relief, it is not to say that other frequencies would not work just as well or even better. Having access to a wide variety of frequencies lets you cover more ground in the body, since the body will tend to pick and choose what frequencies it needs at a given time (and then ignore the rest). Additionally, what frequencies your body wants today could be different tomorrow or next week.
Intensity levels vary pretty dramatically between PEMF systems. It’s important to note that intensities are all relative – no consumer PEMF system produces intensities as high as MRI machines. So in the world of PEMFs, “high intensity” and “low intensity” are totally relative. Just as a wide variety of frequencies have been studied tremendously, so have a wide variety of intensities.
Not many PEMF systems exist within what we would consider to be a ‘medium’ range – it’s mostly either extremely low intensity or relatively high intensity. It’s not uncommon for manufacturers and distributors of low intensity systems to claim that higher intensities are unnecessary or even harmful (not true), or for manufacturers and distributors of high intensity systems to claim that lower intensities are ineffective (also not true).
The truth is in the theme of this buyer’s guide – it all depends on what you need. Are you a practitioner who needs to provide rapid relief from musculoskeletal pain? Low intensities aren’t going to be your best option. Are you an electro-sensitive person who wants to bring about subtle changes to an already over-stimulated body? High intensities may aggravate you.
The intensity of a PEMF system is often tied to how quickly you can expect to see results with that system, with higher intensities generally producing faster results (especially in terms of pain relief). But this is not to say that you would not achieve pain relief with lower intensities – it may just take a bit longer.
Some PEMF systems use a philosophy called “graduated intensity” where the magnetic field intensity varies at different points on the applicator. For example, you may see a PEMF system with a higher intensity at the feet than at the head (we often recommend customers flip the mat around in this scenario so that the head gets a stronger treatment, depending on the condition(s) being treated), or a system that has higher intensity along the center of the mat (where the spine would be) than on the sides. This isn’t really a pro or a con, just a different philosophy from a given manufacturer.
Long-term use of both low and high intensity PEMF systems are considered to be safe.
Waveforms can be downright confusing for consumers, but they are an often-cited parameter when comparing one PEMF system to another. A huge variety of waveforms exist in nature, in the body, and in PEMF devices. The most common are sinus, sawtooth, and square, though there are trapezoidal, rectangular, impulse, triangular, and many other different options in engineering.
waveforms PEMFIt’s important to note that within each loosely-defined waveform exists a huge range of variation. So there is no cut-and-dry sine wave, for example. Some manufacturers talk about a NASA square wave. There is a NASA square wave, but it’s different from all other square waves and only existed in the original NASA research which was done more than a decade ago. So while many PEMF systems produce a square wave, none produce the literal NASA square wave (which, in subsequent NASA research, was tweaked).
The main reason waveforms are important is because they either mimic (enhance) or counteract (diminish) processes in the body. Waveforms also tend to be tied to intensity – square waves tend to be able to produce higher intensities than sinus waves, for instance.
Most PEMF systems produce a single waveform. Some produce one waveform on a full-body mat and another waveform on the pillow applicator. Some have the option to change which waveform you’re using for a given program. While this variety is an attractive feature, waveform should probably not be the deciding factor in terms of which PEMF system will be best for your needs.
The two other most frequently cited aspects of PEMF systems are the coil configuration and the application area.
All PEMF systems use copper coils to produce the desired magnetic field. But the configuration of those coils can vary system to system. Some have tightly wound coils that are all the same size, some have coils wound concentrically, and some have varying sizes of coils spread out in varying patterns within a mat. All of these configurations will produce a magnetic field as designed by the manufacturer. Some configurations lend themselves to a higher intensity magnetic field, some produce a more uniform field across the surface of an applicator, and some intentionally focus the magnetic field on one part of the mat. There is no right or wrong, just differing objectives.
Application area refers to how much of the body is being treated with the magnetic field – is it a full-body system or a local system? Full-body systems almost always come standard with a smaller applicator as well. Within a given brand, the full-body mat produces lower intensity than the smaller pad. Many local systems produce higher intensity than full-body systems. This is because you can stimulate a small group of tissues with more intensity than you can when you’re stimulating the entire person.