What is ALS?
ALS – fully called amyotrophic lateral sclerosis – is a slowly progressing disease caused by the gradual destruction of the nerve cells that run to the muscles under voluntary control (motor nerves). The disease usually starts in the limb muscles furthest from the trunk and gradually spreads towards the centre.
The process is gradual:
- Muscle strength decreases
- The muscles begin to waste away (atrophy)
- Paralysis eventually develops
- Increasing muscle stiffness (spasticity) and contractures (shortening of the tendons)
- Pain caused by these changes
Quality of life is determined mainly by the progression of muscle weakness. There is currently no cause-specific treatment for the disease, but symptoms can be slowed and relieved. Doctors may prescribe medicines, and in addition, movement therapy and muscle stimulation are particularly important.
Key point
Three pillars work together in ALS care: medication + regular physiotherapy + functional electrical stimulation (FES). What makes FES special is that it changes in line with the changing stage of the disease: in the early stage, conventional EMS/NMES is needed; in the advanced (denervated) stage, selective stimulation is needed. That is why it is worth choosing a versatile device that provides both.
The three pillars of ALS care
The disease requires regular intervention in three areas – together, these provide the better clinical outcome:
Medication prescribed by a neurologist is one way of slowing the disease. Appropriate medicines may moderate disease progression and treat symptoms such as cramps, pain and spasticity. Regular check-ups with the treating doctor are essential, both to assess effectiveness and to monitor side effects.
The more you neglect movement, the faster your muscle condition may deteriorate. Many people misunderstand what physiotherapy means: it is NOT the 10–15 minutes of movement carried out in the physiotherapist’s presence. The key is regular repetition at home.
Your physiotherapist will show and teach you movements and exercises suited to your current condition. Every few weeks, the exercises may also change as your condition changes. That is why you need regular consultations.
Frequency at home: at least 3–4 times a day, with exercises lasting at least 5–10 minutes each time. More is better. Without regular movement, muscle condition deteriorates quickly.
Most Hungarian-language medical information sites do not even mention functional stimulation (FES) – although it could be used successfully if doctors and patients knew about it.
FES is an electrotherapy method, in practice muscle stimulation, intended to restore a given function or ability, or in ALS to preserve it for as long as possible. Properly applied muscle stimulation, according to clinical practice, may delay the spread of muscle weakness, relieve stiffness, reduce pain, support bladder and bowel control, and support respiratory muscle function.
The combination of FES and physiotherapy provides the better outcome.
Why is ALS stimulation special? – The changing need for stimulation
In ALS, the muscle–nerve connection is damaged in a way that changes over time. This is one of the disease’s most distinctive features, and it determines which stimulator you need:
| ALS stage | Motor nerve status | Suitable stimulation | Waveform |
|---|---|---|---|
| Early stage | The nerve is partly functional – muscle weakness and initial spasticity are present | Conventional EMS/NMES or ETS (synchronised with voluntary attempts) | Biphasic square wave |
| Intermediate stage | The motor nerves of some muscles are partly or completely destroyed, while others remain intact | Both are needed – a different programme for each muscle | Biphasic square wave + selective stimulation (triangle/trapezoid) |
| Advanced stage | The muscle has become denervated and receives no nerve impulse | Selective stimulation (denervated stimulation) | Long triangle or trapezoid pulse |
NOT selective stimulation at first! But later, yes
At the beginning of the disease, when the motor nerve is still partly functional, ALS corresponds to central paralysis. At this point, you need conventional biphasic square-wave EMS/NMES, NOT selective stimulation. Selective stimulation on a muscle with an intact nerve is unpleasant, painful and may increase spasticity.
As ALS progresses, however, individual muscles become denervated – and THEN selective stimulation becomes the appropriate response. A physiotherapist or neurologist assesses this using EMG and a time/intensity diagram, and the stimulator programme must be changed accordingly.
That is why it is worth choosing a versatile device that provides both types of stimulation. For a detailed explanation, see the selective stimulation pillar article.
Why is the cheap ‘shop-bought’ stimulator unsuitable?
Cheap muscle stimulators that are generally available usually deliver a simple square-wave pulse. They are designed for healthy muscle. A diseased muscle supplied by a damaged motor nerve requires a very precise impulse, which only a good-quality, medical-device-grade unit can provide. A poor-quality impulse is more likely to harm than help – it is like trying to crack a nut with a 10 kg concrete-breaking hammer.
How does FES help manage ALS symptoms?
FES may support people living with ALS in several ways. It is worth reviewing the options below in light of your current symptoms:
Properly adjusted functional stimulation relaxes the muscles. It reduces, or at least moderates, spasticity and involuntary muscle twitching. These involuntary twitches can occur spontaneously at any time and are particularly troublesome when they occur as you begin a deliberate movement.
Important: stimulation must be adjusted to your condition, the particular muscle and the treatment goal. One setting provides muscle relaxation and another strengthening – you cannot affect all your muscles in the same way with the same pulse. Modern muscle stimulators have menus: after selecting a muscle-relaxation treatment, you can choose the area to be treated from a list (forearm, upper arm, trunk, abdomen, buttocks, thigh, lower leg).
Intensity: for muscle relaxation, it is enough for the treatment to cause barely perceptible twitches – a visible muscle contraction is not necessary. Increasing the intensity may increase effectiveness, but do NOT cross the pain threshold under any circumstances.
Duration: clinical studies used 60–120 minutes of stimulation per day, divided into several shorter sessions. As a general rule, treat one muscle group (e.g. the thigh muscles) for 25–30 minutes per day, up to a maximum of 90 minutes. Two or three short sessions are preferable to one continuous session.
When the muscle is still innervated and voluntary movements are possible, it is worth using muscle stimulation NOT passively (not just while sitting), but together with the fullest possible range of the movement associated with that muscle.
For example, if you treat the flexor muscles of your forearm, which help move your wrist, move your wrist through as much of its range as possible when you feel the stimulation pulse. Bend your wrist as far as you can, then let it return during the stimulation pause.
This helps because stiffness is relieved and the muscles and tendons relax, allowing a less painful and larger movement. If you stretch the muscles and tendons passively, without stimulation – for example, by pushing down with your other hand – you may cause micro-injuries, which can increase stiffness in the long term.
Even in severe ALS, relaxing the joints and muscles is very important. Joints that are easier to move help your carers position you properly and therefore help prevent pressure sores.
Your muscles may appear stronger simply because spasticity has decreased – even though you have not yet had a muscle-strengthening treatment!
Another role of muscle stimulation is to ‘teach’ the muscles. Regular stimulation improves the coordinated function of muscle fibres and the ‘synchronisation’ of the fibres involved in contraction. Stimulated muscles can work more efficiently and precisely – the effectiveness of your movements may improve.
In addition to muscle relaxation, it is important to plan strengthening stimulation so that you perform it, where possible, together with voluntary movements. Treatment may improve muscle strength, make the muscle more resistant to fatigue and improve coordination.
Respiratory infections are less common while mobility is preserved. However, if you are confined to a wheelchair or bed, or if the trunk muscles also become affected, your chest is compressed when lying or sitting. You cannot ventilate your lungs properly, which significantly increases the risk of respiratory infections.
Weakness of the muscles that move the chest also affects your cough, making it harder to clear the airways. In ALS, one of the most serious problems is reduced coughing ability – FES can therefore also be used to support coughing and keep the airways clear.
Strengthening the abdominal and trunk muscles and relieving their stiffness may improve breathing for several reasons:
- More relaxed muscles allow greater room for chest movement, making it easier for the lungs to expand during inhalation.
- Better coordination of the expiratory muscles contributes to improved ventilation.
- A stronger cough may reduce the risk of respiratory infections by clearing the airways.
Several belt-like accessories are available for muscle stimulators. Placed over the abdomen or back, they simplify treatment.
Pressure sores are common in areas exposed to prolonged pressure. Several factors play a role: stiffness, joint contracture, immobility due to paralysis and impaired circulation caused by pressure from the surface.
Functional stimulation may reduce the risk:
- Reducing stiffness – helps you change position more often and adopt a better position.
- Increasing muscle mass – ‘improves padding’, cushions pressure on the bones and distributes pressure on the skin more evenly.
- Improving circulation – muscle contractions may increase blood flow in the treated area, also supporting oxygen supply to the skin.
If a pressure sore does develop, FES may speed up the healing process. Improved blood flow improves oxygen supply to the skin and muscle, which may accelerate connective-tissue and scar formation and minimise infection. The chance of healing is better when the wound affects only superficial layers; the deeper it is, the slower and more difficult healing becomes.
As ALS progresses, the pelvic floor sphincter muscles may also weaken, causing incontinence symptoms. Specialised stimulation of the pelvic floor muscles, using a probe or surface electrodes, may support bladder and bowel control. This must be planned and introduced exclusively by a urologist, gastroenterologist or physiotherapist; it can then be continued at home using the appropriate protocol.
Which device is suitable for people living with ALS?
In ALS, the appropriate type of stimulation changes as the disease progresses. You can therefore choose between two strategies:
- Versatile, ‘does-it-all’ device – a single device that can be used throughout the disease (conventional EMS + selective stimulation in one).
- Combining specialised devices – an early-stage device (ETS or conventional NMES) plus a late-stage device (selective).
In ALS, strategy 1 is generally more favourable because you do not need to buy another device later.
Strategy 1 – Versatile devices (recommended for ALS)
These devices provide both selective stimulation AND conventional NMES, so they can be used in both phases of the disease:
Genesy 3000 – professional-level versatile device
The top model in the Globus Genesy range. Selective stimulation programmes for denervated muscle plus extensive NMES programmes for training muscles with intact nerves and for rehabilitation. Can be used throughout the course of ALS, with numerous clinically documented protocols. Four-channel, professional-level device.
Genesy 1500 – top-of-the-range home device
The premium home-use member of the Genesy range: it provides both selective stimulation programmes AND extensive NMES functionality. A suitable choice for ALS because it can be used throughout the disease – you do not need to change devices later.
Genesy 600 – versatile entry-to-mid-range device
The entry-to-mid-range member of the Genesy family: it includes selective stimulation programmes AND NMES functionality. A cost-effective choice for people living with ALS, used according to a physiotherapist’s protocol.
Strategy 2 – Stage-specific devices
In the early stage (intact or partly intact motor nerve):
DuoBravo N – ETS specialist (recommended early-stage choice)
ETS (EMG-Triggered Stimulation) technology may be particularly valuable in the early stage of ALS. It starts stimulation in response to the patient’s own voluntary attempt, supporting motor learning and preservation of muscle strength through coordination of voluntary movement and stimulation ‘reinforcement’. It does NOT include selective stimulation programmes, so it is no longer sufficient in the advanced stage.
Genesy 300 Pro – conventional NMES (early stage)
A conventional NMES device specifically suitable for the early stage of ALS. It does NOT include selective stimulation programmes AND does NOT include ETS functionality – it will no longer be sufficient in the denervated phase.
In the advanced stage (denervated muscles):
PeroBravo – selective stimulation specialist
In the advanced stage of ALS, when individual muscles become denervated, PeroBravo is specifically suitable for selective stimulation, with extensive capabilities and specialised adjustment options. Triangle, trapezoid and square pulse programmes for individual denervated muscles, with adjustable parameters. For a detailed explanation, see the selective stimulation pillar article.
Regaining lost muscle strength (EMS rehabilitation) → Frequently asked questions
As soon as possible, after diagnosis. Muscle condition deteriorates rapidly as the disease progresses – stimulation started earlier may help preserve muscle strength, mobility and quality of life for longer. After consultation with a neurologist, a physiotherapist can help set up the initial protocol.
At the beginning of ALS, the motor nerve is still partly functional – the muscle is then in the ‘intact nerve’ stage. Selective stimulation, with a long triangle or trapezoid pulse, causes an unpleasant or even painful sensation in muscle with an intact nerve and may increase spasticity. Conventional biphasic square-wave EMS/NMES is appropriate. When the muscle becomes truly denervated, because the motor nerve has been destroyed, you can switch to selective stimulation – this is determined by a physiotherapist or neurologist using EMG.
Clinical studies used 60–120 minutes of stimulation per day, divided into several shorter sessions. General guidance:
- One muscle group (e.g. thigh): at least 25–30 minutes per day, maximum 90 minutes.
- For several muscle groups: total daily treatment time may be 1–3 hours.
- Divided into several sessions: 2–3 times per day.
Your physiotherapist should always determine the exact protocol according to your current condition.
NO. FES complements physiotherapy; it does NOT replace it. The two methods together may provide a better result than either alone. In fact, the better outcome is achieved when you perform FES combined with voluntary movements – for example, while the stimulator treats the forearm muscles, you also try to move your wrist actively.
Not recommended. Cheap muscle stimulators costing HUF 3,000–10,000 are designed for healthy muscle and deliver a simple square-wave pulse. ALS-affected muscle, where the motor nerve is damaged, requires a very precise impulse. A poor-quality impulse may do more harm than good. Choose a professional medical-device-grade unit, such as one from the Genesy range or PeroBravo.
Realistic expectation: FES is NOT a cause-specific treatment for ALS – it does not eliminate or stop the underlying disease. What it may achieve is to delay the progression of muscle weakness by maintaining muscle mass and tone, relieving stiffness, reducing pain and improving breathing and coughing ability. Clinical studies have documented these quality-of-life benefits. Preserving quality of life and functional ability is a key value in ALS.
Before starting treatment
FES is generally safe in ALS, but there are situations in which it cannot be used. Always discuss it with your treating doctor or neurologist before starting treatment.
When should you be cautious?
- Implanted pacemaker or defibrillator – the electrical impulse may interfere with the implanted device
- Selective stimulation at the BEGINNING of the disease – unpleasant on a muscle with an intact nerve and may increase spasticity
- Active cancer in the treatment area – electrical stimulation should be avoided in the treatment area
- Pregnancy – consultation with a gynaecologist is mandatory
- Epilepsy – electrical stimulation may provoke a seizure (relative contraindication; specialist consultation is mandatory)
- Skin inflammation or an open wound at the electrode site – electrodes must not be placed on damaged skin
- Thrombosis or thrombophlebitis in the treatment area – muscle contraction in the affected area may be dangerous
- Severe loss of sensation in the treatment area – extra caution is needed because you may not feel skin irritation
- Severe cardiovascular disease – uncontrolled high blood pressure or recent myocardial infarction
- Use of a cheap, industrial-quality stimulator – the damaged nerve requires a precise impulse; an ordinary stimulator is unsuitable
Complementary treatment, not a standalone therapy
Home FES is a complement to ALS rehabilitation. It does not replace neurological care, medication or physiotherapy. Diagnosis, treatment planning and follow-up must always be carried out by a healthcare professional. For a detailed list of contraindications, see the article on electrotherapy contraindications.
Summary – Quick overview
Sources
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