PEMF Background

On this page, we explain the essentials of PEMFT.

Electromagnetism

Electromagnetism: the interaction between electricity and magnetism.

It is difficult to grasp intuitively electro-magnetism, leading to widespread misunderstandings about PEMFT.

Maxwell was the first to describe ALL electromagnetic interaction in four differential equations.

His four Laws fully describe the electric and magnetic fields arising from distributions of electric charges and magnetic fluxes and how those fields change in time.

Einstein: "I stand on the shoulders of Maxwell."

Generating a Magnetic Field

Electric currents: symbol (I), unit (A) amperes, create magnetic fields, which have a Magnetic Field strength: symbol (H), unit (A/m) Amperes/meter, and a Magnetic Flux Density, often called Magnetic Flux: symbol (B), unit (T) Tesla.

Generating an Electric Field

Changing (Pulsed) Magnetic Flux Densities: symbol (dB/dt), unit (T/s) Tesla/second, do induce electric fields: symbol (E), unit (V/m) Volt/meter.

The third law of Maxwell, describing this effect, shows us that the Induced Electrical Field (E) by PMFT is ONLY a function of how quickly the magnetic flux changes (in mathematical terms: dB/dt).

The magnetic field's strength (H), magnetic flux (B) itself, or signal frequency (f) is not essential for effectively inducing an Electric Field.

The only critical parameter is how quickly the Magnetic Flux changes at a particular moment!

Relation between B and H of the same magnetic field

NOTE: This paragraph serves as a note to complete our explanation.

The relationship between the magnetic field strength (H) and the magnetic flux density (B) is often complex and nonlinear, sometimes displaying a hysteresis effect.

Fortunately, for most PEMF devices, the relation between B and H is generally fixed and described by a constant (during normal operation).

The magnetic flux density (B) in PEMF is often referred to as the "magnetic field," which is incorrect but not problematic because (in most cases) the difference can be considered to be a "constant factor."

Thanks to Maxwell, PEMFT is well understood mathematically.

Simplified 3th Law of Maxwell

PEMF IN SIMPLE WORDS

In a PEMF device, a pulsed electrical current flowing through an electric coil generates a pulsed magnetic flux.

When a cell in the body is exposed to this pulsed magnetic flux, an electrical field is induced around the cell, generating beneficial effects.

PEMF Signal Parameters

Wave Form = PEMF Effectiveness

In the previous section, "Generating an Electric Field," we showed that the PEMF-induced electric field around a cell depends on how quickly the Pulsed Electro Magnetic Flux changes.

This means that PEMF devices using slowly changing signals, such as a triangular or sinusoidal waveform, are ineffective and will not generate an adequate electrical field around the cells.

The best performance is achieved with rapidly changing signals, like a square wave signal.

LOREM X rapid changing square waveform

Signal Frequency

Frequency: symbol (f), unit Hz, cycles per second.

Frequency is not dB/dt:

A body cell does not know the signal's frequency (what will happen in the coming seconds), but it does feel the change in the magnetic flux (dB/dt) at a particular moment.

And yes, for a particular waveform, e.g., a sinus, the dB/dt of the signal will increase with increasing frequencies. However, the influence of the frequency on the PEMF electric field-inducing effectiveness is neglectable compared to the influence of the waveform (rapid changing waveforms vs slow changing waveforms)

Nevertheless, the frequency of the signal is essential for:

SAFETY

Higher frequencies of electromagnetic radiation can be hazardous and damage body cells. For this reason, LOREM X protocols always stay in the safe, Extreme Low Frequency (ELF) range, with a maximum of 300 Hz.

LOREM X protocols seldom go above 100 Hz.

MECHANICAL CELL STIMULATION

In addition to the induced Electric Field over a cell, PEMF also stimulates cells mechanically. Because different families of cells have different geometry, volume, and mass, they will have different mechanical resonance frequencies, which means that only specific frequencies can optimally stimulate particular cells. For this reason, good FEMFT results are often obtained in the 1- 12 Hz frequency range.

MECHANOSENSITIVITY

Mechanosensitivity is a scientific term describing the decreased effect of continuous multiple activation pulses or the increased healing effect of cells when they have a recovery time between activation pulses (or trains of activation pulses).

Increased performances have been reported, with recuperation time as short as 14 seconds and performance increases of +66 - +190%.

In some Lorem X protocols, the pulse frequency is lowered to 0.05 Hz. This means that every 20 seconds, a short, efficient square pulse is followed by a sufficiently long recovery period to (i) restore cells' mechanosensitivity and (ii) maximize the effects of mechanical loading (exercise) regimens.

LOREM X Protocols use frequencies between 0.05 Hz and 300 Hz.

Magnetic Strength

Magnetic Strength can be described by Magnetic Field (Strength) (H) or by Magnetic Flux (Density).

Magnetic Field: symbol H, unit A/m

Magnetic Flux: symbol B, unit T (Tesla)

In FEMF, Magnetic Field and Magnetic Flux are often (wrongly) used interchangeably.

Like frequency, the magnetic strength of a PEMF device (either the magnetic field or magnetic flux) is not a parameter in the third law of Maxwell.

As a result, the magnetic strength (magnetic field or magnetic flux) of a PEMF device is not essential for effectively inducing an electrical field around a cell.

Nevertheless, a minimum device magnetic strength (5 - 50 μT) in the neighborhood of the earth's magnetical strength (50 μT) is required. The treating magnetic flux should be noticeable by the cells!

As said before, the only important parameter defining the effectiveness of a PEMF device is how quickly the magnetic flux changes (dB/dt), meaning the used waveform.

Magnetic strength is often used as a sale argument, with vendors telling how much more Tesla or Gauss the device has, but when the same high Gauss device has a low dB/dt, the "strong" device will simply not generate an effective PEMFT effect.

SAFETY

High magnetic field strengths can heat body cells.

First-generation Transcranial Magnetic Stimulation (TMS) devices used high magnetic strengths, which resulted in an unwanted temperature increase in the brain and a recall of the devices.

When using a "strong" PEMF device, follow strict user manual instructions.

LOREM X protocols ensure effective PEMF therapy while utilizing only safe (international standards) maximum magnetic strengths (magnetic flux) of approximately 170 μT, with a low duty cycle of only about 10%.

Signal Duty Cycle

Duty Cycle: symbol DC, unit %.

When the signal is high, we call this "on time." To describe the amount of "on time," we use the concept of duty cycle (DC), measured in percentage.

The DC of a PEMF signal is not a constant but should be a function of the frequency.

It is not beneficial for the treatment that a signal stays up for a long time, but it should be sufficiently long.

The signal's duty Cycle controls these aspects and is frequency-dependent.

LOREM X Protocols use effective Duty Cycles between DC = 0.1% and 15%.

Signal Variety

When stimulated, a body becomes used to that specific stimulation, and the stimulation effect decreases over time. The same happens with PEMF stimulation.

PEMFT stimulation efficiency decreases when the signal characteristics remain constant during treatment. The decline in effectiveness typically starts after minutes (see above Mechanosensitivity).

LOREM X: The strength of using a Samsung Galaxy tablet as a signal generator is that we can program high-quality signals with a good Signal Variety, sections with different frequencies, frequency sweeps, and frequency modulation with optimized modulation depth and range to maintain productive stimulation for longer than a few minutes.

Signal Polarity

The Lorem X uses DC signals.

AC signals are used in microwave furnaces for high efficiency, but they should not be used in PEMF devices.

MECHANOSENSITIVITY

Diffent Types of PEMF Devices

One Coil PEMF

The issue with a single coil is the limited penetration depth of the magnetic field. The magnetic strength decreases quadratically, reaching only 25% at 5cm and 3% at 15cm from the coil. The effectiveness, dB/dt, also decreases in the same manner.

Attenuation-of-magnetic-field-strength-along-common-coil-axis-from-surface-of-circular.png

Penetration depht Drawing: Filippos Marketos

Additionally, the magnetic field is irregular, dropping to low levels in the center of the coil. Despite these limitations, it is suitable for treating the skin.

Butterfly Coil PEMF

The butterfly or eight coil is often used in Transcranial magnetic stimulation. It amplifies the magnetic field at ONE POINT, the intersection point of the two coils, by a factor of about two.

However, because the penetration depth of a single coil is shallow, the penetration depth remains constrained.

Tilted Butterfly Coil PEMF

The coils are now tilted to enhance the depth of penetration, potentially tripling penetration depth

D-B80MagventureDeep-transcranial-magnetic-stimulation-(TMS).png

Mattress PEMF

Mattress PEMF devices contain several coils integrated into the mattress. However, these devices encounter the issue of limited magnetic field penetration, similar to single or butterfly coil devices. The coils are covered with at least 5mm of mattress material, which causes most of the generated magnetic field to remain within the mattress and not penetrate outside. An already weakened magnetic field emerges from the mattress surface, which rapidly declines further with distance from the surface.

Additionally, the magnetic field is irregular, reaching almost zero at large areas of the mattress surface (center of coils and between coils).

These devices can be used for localized skin treatment (for the skin touching the mattress, located just above the outer diameter of the coils), but they are unsuitable for whole-body treatments.

Helmholtz Coil PEMF

A Helmholtz coil is a device that generates a large, nearly uniform magnetic field between its two coils. Because of the characteristics of a Helmholtz coil, the coils would need to be huge to treat a person. However, an effective Helmholtz PEMF device with large coils requires dangerous high voltage and high electrical currents, making it impractical. When safe voltages and currents are used, only non-effective small magnetic fields are generated, thousands of times smaller than the Earth's magnetic field, and hidden by it. Manufacturers of this type of device claim that the low magnetic flux (pico Tesla instead of microTesla) is beneficial.

Moreover, a human Helmholtz PEMF device is inefficient, as much of the magnetized volume between the coils goes unused. While a Helmholtz coil is admirable, it is not practical for a human PEMF device.

Multiple Axial Coil PEMF

Multiple Axial Coil PEMF devices (coil distance = r coil) generate a large and uniform magnetic flux inside the large coil area, magnifying the magnetic flux generated by each coil.

Inside a Helmholtz coil, the magnetic flux is 150% of the flux generated by one coil. Three axial coils (Maxwell coil) produce a uniform magnetic flux that is 200% larger than the flux generated by one individual coil.

Efficiency:

When designing the Lorem X bed, we aimed to make the coils as small as possible to achieve excellent efficiency, in contrast to the large PEMF Helmholtz coils, which have low efficiency.

A test demonstrated that a more prominent person could easily fit hips, stomach, and shoulders into 60 cm diameter coils.

The LOREM X BED Applicator coils also have a straight section below the bed to increase efficiency further, eliminating non-used magnetized space (this modification does not significantly affect the achievement of a uniform magnetic field inside the coils).

Magnetic Field Magnification:

Knowing the diameter of the coils, the number of needed coils is known. Eight coils are required to cover a 6.6-ft person (the distance between coils = coil radius).

Eight axial coils produce a homogeneous magnetic flux 500% larger than the flux of one individual coil!

Helmholtz

References

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