Here’s the response I got from Marc Pro –

Looks like you might be able to get the same results from a TENS unit – depending on the settings available on it.

A
TENS device is typically used at higher frequencies where a constant
“buzzing” feeling is delivered as opposed to individual muscle
contractions. That is desirable for the cleared indications of a TENS
device. Depending on the device it is possible
to lower the frequency to a point where “pumping type” muscle
contractions might be obtained. To move nourishment and waste, you
definitely want muscle pumping (though as you point out that is not an
indication of TENS devices).

Various
TENS devices have various technical limitations, but there are some
commonalities. Because of the very basic square (on or off) waveform, it
is common for the signal to get quite uncomfortable when turned very
high; and without turning it very high the contractions are not strong
enough to move a significant amount of nourishment and waste. Again we
don’t blame the TENS devices; they were not intended to be muscle
stimulators. The higher voltage and harsher signal typically created by a
TENS will often start to cause muscle fatigue after extended periods of
use. This is also common with many cleared muscled stimulators. This is
not a problem when trying to tone or re-educate muscles (which is the
most common use of muscle stimulators); however, fatigue is obviously
contradictory to the recovery goals of Marc Pro.

Simply
stated, what makes Marc Pro’s technology unique is that we’re able to
get a muscle contraction that is as strong and typically stronger than
any other TENS or cleared muscle stimulator, but do so without causing
any fatigue to the muscle. This makes us poor at trying to build muscle
(what other products often try to do, but we don’t believe in much), but
makes us really good at recovery. Our unique waveform, lower voltages,
lower frequencies and very long pulse duration all contribute to this
strong, yet non-fatiguing contraction. Check out the “Marc Pro
Technology and How It Is Different” tab on the following page of our
website to read some more details: http://www.marcpro.com/how-it-works

If you have any further questions, feel free to email us at [email protected]