In addition to helping the injury heal more quickly, it also helps diminish the pain associated with injury. E-Stim works as a pain gate. Painful stimuli are carried on small nerve fibers, they can be myelinated(insulated, similar to electrical wires) or unmyelinated and most importantly they travel SLOW. Non-painful stimuli are carried on large nerve fibers, they are myelinated and travel FAST. It basically becomes a race to the brain, because non-painful stimuli (the E-Stim current) travel on FAST fibers and they get to the brain more quickly. Painful and non-painful stimuli compete for the same receptor, so if the non-painful stimuli gets there first, it essentially blocks the pain. That is why it is often referred to as the “pain-gate”.