martn76,
That is not correct. All electrostimulators using pads, Compex, Globus and other electrostimulators, including those that utilize Russian protocols, all recruit muscles indirectly through the muscle nerve plate.
As a matter of fact, Globus has a clinical portable version (Genesy sold to Athletic Trainers and Physiotherapists), which has both square waveforms and Russian protocols in it. When I connect this unit to my leg, and switch from rectangular waveform to Russian waveform, there is no difference whatsoever, except for the weakening of the contraction with Russian. If you read the EMS Digest appendix on Russian currents it is explained why a Russian contraction is weaker (implicitly shorter pulsewidth).
You even quoted the passage from the EMS Digest that implies that direct stimulation cannot happen with pads.
to excite nervous fibers it is necessary to change the potential of the membrane by only 15 mV. Comparing this value to the 35 mV calculated for muscle fibers, the difference is huge: one will need 57% more.
This means that if you need to dial your unit to 100 to trigger the nerves, you will need to dial it to 157 to trigger the muscle directly. But by the time your muscle is triggered directly, it was already contracting from the nerve-initiated signal.
Direct muscle stimulation (when needed) is normally done In Vivo. I.e. the researcher or the doctor touches the muscle fiber with a microscopic probe (normally they have to slice through the skin of the animal to do this). It may be done on patients who have been denervated from a stroke or an injury, for particular diagnosis of the health of the nerve-muscle connection.