One word, three completely different tools
"Electrotherapy" covers several technologies that share only one thing: current delivered through the skin. What that current does depends entirely on its parameters — frequency, intensity, waveform. Confusing them is like confusing a scalpel with a stethoscope because both are found in hospitals.
TENS — talking to the nervous system
Transcutaneous Electrical Nerve Stimulation targets nerves, not muscles. Its purpose is pain modulation, built on Melzack and Wall's gate control theory (1965): non-painful input can "close the gate" on pain signals travelling to the brain.
- High-frequency TENS (~80–120 Hz): comfortable tingling, fast-acting relief, ideal during activity
- Low-frequency TENS (~2–10 Hz): stronger pulsing that stimulates endorphin release — slower onset, longer-lasting effect
What it does not do: heal tissue or strengthen muscle. TENS manages the alarm while other treatments fix the fire. We use it to keep patients moving comfortably during early rehabilitation — because movement is itself therapeutic.
EMS — making muscle work
Electrical Muscle Stimulation uses stronger currents that reach the motor nerves, producing actual muscle contractions. Its evidence-based role in rehabilitation is very specific: fighting muscle inhibition.
After surgery or significant injury (especially knee), the nervous system partially "switches off" surrounding muscles — a protective reflex called arthrogenic muscle inhibition. You cannot fully activate a quadriceps that your own nervous system is suppressing, no matter how hard you try. EMS bypasses the inhibition and makes the muscle contract, preserving mass and re-establishing the neural pathway (Maffiuletti, 2010).
We use EMS most in early post-surgical knees and in patients whose voluntary activation is measurably impaired — then phase it out as voluntary strength work takes over.
Microcurrent (MENS) — whispering to the cells
Microcurrent is different in kind, not just degree: it uses currents a thousand times smaller — microamps, below the threshold of sensation. You feel nothing at all. The target isn't nerve or muscle but cellular repair metabolism: research suggests microcurrent in physiological ranges supports ATP production and protein synthesis in healing tissue (Poltawski and Watson, 2009).
Its role in our programmes is tissue-healing support in the early phases — often alongside MLS laser, which works on complementary cellular mechanisms.
The comparison at a glance
- TENS → target: nerves → effect: pain relief → you feel: tingling
- EMS → target: motor nerves/muscle → effect: contraction, anti-inhibition → you feel: your muscle working
- Microcurrent → target: cell metabolism → effect: repair support → you feel: nothing
The part that matters most
None of these is a standalone cure — and any clinic that builds a treatment plan on electrotherapy alone is selling comfort, not rehabilitation. In our programmes, electrotherapy has a defined job in a defined phase: TENS keeps you moving, EMS wakes up inhibited muscle, microcurrent supports early tissue repair — and all of them exist to enable the progressive loading that actually rebuilds you.
Want to know which modalities your recovery actually needs? Book an assessment at Bruno Physical Rehabilitation, Ipswich.
References
- Johnson, M.I., Paley, C.A., Howe, T.E. and Sluka, K.A. (2015) 'Transcutaneous electrical nerve stimulation for acute pain', Cochrane Database of Systematic Reviews, 6, CD006142.
- Vance, C.G., Dailey, D.L., Rakel, B.A. and Sluka, K.A. (2014) 'Using TENS for pain control: the state of the evidence', Pain Management, 4(3), pp. 197–209.
- Maffiuletti, N.A. (2010) 'Physiological and methodological considerations for the use of neuromuscular electrical stimulation', European Journal of Applied Physiology, 110(2), pp. 223–234.
- Poltawski, L. and Watson, T. (2009) 'Bioelectricity and microcurrent therapy for tissue healing — a narrative review', Physical Therapy Reviews, 14(2), pp. 104–114.
- Melzack, R. and Wall, P.D. (1965) 'Pain mechanisms: a new theory', Science, 150(3699), pp. 971–979.