ALS disease and functional muscle stimulation (FES)

ALS is still incurable. However, its symptoms can be treated and reduced, and disease progression can be slowed. Doctors may recommend drug therapy.

Because ALS affects the condition of the muscles, movement therapy plays a crucial role in treatment. The more you "neglect" movement, the faster the muscle condition can deteriorate and the faster the disease may progress.

If you receive a diagnosis of ALS, definitely find a physiotherapist and see them regularly.

Many people misunderstand what physiotherapy means. They think the important part is the 10–15 minutes of exercise in the presence of the physiotherapist. But that is NOT the point!

The physiotherapist will show and teach you movements and exercises appropriate to your current condition. Every few weeks — taking changes in your condition into account — the exercises you should or can perform will change. Therefore you need regular consultations with your physiotherapist.

Physiotherapy will be effective and improve your condition only if you regularly repeat the movements learned at the physiotherapist. In my opinion, exercising at least 3–4 times a day for at least 10–15 minutes each time can have an effect. More is better!

Without regular movement, muscle condition deteriorates quickly.

You can enhance the effect of physiotherapy with muscle stimulation. This article presents that possibility.

Functional stimulation (FES) in home care for ALS

Most Hungarian-language medical information sites do not even mention functional stimulation (FES) as a method to reduce symptoms and slow deterioration. They may mention physiotherapy as an option, but rarely go into detail. Yet FES could be used successfully… if doctors and patients were informed about it.

Functional stimulation (FES) is an electrotherapy method. In fact it is a form of muscle stimulation whose goal is to restore a specific function or to preserve it for as long as possible in ALS.

Stimulation, however, is more complex than taking a pill. There is no universally applicable protocol; not the same treatment is right for every patient, because the order and intensity of symptoms and the pattern of muscle weakness vary between patients. The treatment plan must be made taking your symptoms into account.

Properly applied muscle stimulation helps improve quality of life, delays the spread of muscle weakness, relieves stiffness, reduces pain, and supports maintenance of urinary and fecal continence.

Click here to find devices recommended for treating ALS.

Attention! ALS damages the nerves of the brain and spinal cord; the paralysis it causes is central.
For this condition the so-called selective current (also referred to as denervated) treatments are not suitable.
Selective current treatments will increase muscle stiffness and spasticity, which from the patient’s perspective will appear as deterioration.

I repeat: the appropriate treatment is EMS (also known as NMES) — muscle stimulation using biphasic square waveforms.

A few words about muscle stimulation

During muscle stimulation electrodes must be placed on the muscle's so-called motor points (the points where the motor nerve reaches the muscle), and the small electrical pulses delivered through these electrodes trigger muscle contraction.

The shape, duration, frequency and intensity of the pulse determine how we treat. It can be precisely controlled whether the treatment is muscle-relaxing, strengthening, blood-circulation improving, etc. Of course, one type of pulse relaxes the muscle and another has a strengthening effect.

Most available muscle stimulators use so-called square-wave pulses. These were developed for treating healthy muscles. They are effective in ALS as long as the motor nerve still functions, even if only partially. That means in early ALS you can treat with a general (good quality) muscle stimulator.

Because this is a disease of the motor nerve, I do not recommend starting to treat yourself with a three-thousand-forint "consumer" stimulator! That would be like trying to crack a nut with a 10 kg sledgehammer. With a poor-quality pulse you are more likely to cause harm. The diseased nerve requires very precise pulses, which only a good quality device can provide.

Over time in ALS the motor nerve may be completely destroyed and the muscle becomes denervated, i.e. it loses its innervation. At that point the previously mentioned square-wave stimulation will no longer be effective because it will not elicit contraction. Denervated muscles respond only to long-duration triangular or trapezoidal pulses. Such pulses are provided only by devices specifically designed for denervated muscle treatment; ordinary stimulators usually do not deliver them.

Let us review the reasons you might use functional stimulation.

Reducing spasticity (stiffness)

Properly set functional stimulation relaxes muscles. It eliminates or at least reduces spasticity and involuntary muscle twitches. These involuntary twitches can occur spontaneously at any time, and are especially disturbing if they occur just as you try to initiate a deliberate movement.

As I mentioned, functional stimulation must be set according to your condition, the specific muscle, and the treatment goal. Different settings produce relaxation and strengthening. In other words, it is not possible to affect all your muscles the same way with the same pulse (or the same treatment program).

The good news is that you no longer have to make these settings yourself, because modern muscle stimulators have menu systems and you can choose from a list. For example, after selecting a muscle-relaxing program, you can select the treatment area (e.g. forearm, upper arm, trunk, abdomen, glutes, thigh, lower leg) from another list. The device then knows exactly what to do.

This is a huge advantage: you only need to understand that relaxing and strengthening pulses differ and have different effects. So if stiffness is your problem, select and use the muscle-relaxing program. Strengthening treatments can increase stiffness, so run a relaxing program after strengthening.

In ALS the intensity of the pulse is important. For muscle relaxation it is enough if the treatment causes barely perceptible twitches; a visible contraction is not necessary. Increasing intensity increases effectiveness, but you must never set the intensity above your pain threshold.

Most studies applied stimulation between 60 and 120 minutes daily, and they aimed to give treatments in several shorter sessions rather than one long session. How much treatment you need depends on your condition. If only your arm is affected, you need less treatment time than someone who must also treat trunk muscles, incontinence, etc.

As a general rule I recommend treating a muscle group (e.g. thigh muscles) for at least 25–30 minutes and at most 90 minutes per day. Preferably in two or three short sessions rather than one continuous session.

Functional stimulation reduces spasticity, relieves or eliminates pain, improves bowel and bladder function, and improves the ability to perform voluntary movements.

Maintaining or improving joint range of motion

When a muscle still has innervation and voluntary movements are possible, you should perform muscle stimulation not passively (i.e., not only while sitting), but together with the muscle’s characteristic movement through the fullest possible range of motion.

That is, if you are treating the forearm flexor muscles (which assist wrist movement), feel the stimulation and move your wrist through the maximum available range of motion. Bend your wrist as far as you can, then release it during the stimulation pause.

This is very beneficial because it reduces stiffness, relaxes muscles and tendons, and allows pain-free and larger movements. If you stretch the muscles and tendons passively (without stimulation), for example by pressing down with your other hand, you may cause micro-injuries that will increase stiffness in the long run.

Combining functional stimulation with voluntary movements performed through the full range of motion helps reduce joint movement limitations. This improves mobility and makes movements more efficient, thereby reducing the energy needed for tasks. You will be less exhausted when performing activities.

Even in severe ALS it is important to relax the joints and muscles. Easier-to-move joints help your caregivers position you properly and thereby help prevent pressure sores.

Improving muscle strength or performance

A reduction in spasticity alone can make your muscles feel stronger, even before you perform explicit strengthening treatments!

Another important role of muscle stimulation is "training" the muscles. Regular stimulation improves the coordinated functioning of muscle fibers, the synchronization of the fibers involved in contraction. Stimulated muscles can work more efficiently and precisely, so the effectiveness of your movements improves.

Therefore, beyond muscle relaxation, it is important that strength-increasing stimulation is planned so that you perform it, whenever possible, combined with voluntary movements. Treatments can improve muscle strength, increase resistance to fatigue and improve coordination.

The role of stimulation in preventing respiratory infections

As long as mobility is preserved, respiratory infections are less frequent.

If, however, you become confined to a wheelchair or bed, or your trunk muscles are affected, the sitting or lying position compresses the chest. You cannot breathe properly, and this significantly increases the risk of respiratory infections. Weakness of the chest muscles also impairs coughing, hindering airway clearance and worsening the situation.

One of the most serious problems in ALS is reduced coughing ability, so it is worth using functional stimulation to assist coughing and keep the airways clear.

Strengthening and relaxing the abdominal and trunk muscles can improve breathing for several reasons. Looser muscles allow greater chest movement and facilitate lung expansion during inhalation. Better coordination of expiratory muscles also helps gas exchange. A stronger cough helps clear the airways and contributes to avoiding respiratory infections.

You can also get belt-like accessories for your stimulator that are simply placed on the abdomen or back and simplify treatment.

Reducing the risk of pressure sores

Pressure sores commonly develop in areas exposed to prolonged pressure. Many factors play a role, including stiffness, joint contracture, immobility due to paralysis, and circulation impairment caused by pressure on the surface.

Functional stimulation can reduce your risk. Reducing stiffness helps you change positions more often and achieve better positioning. Increasing muscle mass improves "padding," reducing the direct pressure on the bones and distributing pressure on the skin more evenly.

If a pressure sore does develop, functional stimulation can speed up healing. Muscle contractions can significantly — even up to 300% — increase blood flow to the treated area, which is fundamental to healing. It improves oxygen supply to skin and muscle, accelerating connective tissue and scar formation and minimizing infection. Healing chances are of course better the more superficial the layers affected are. The deeper the wound, the slower and more difficult the healing.

To summarize what has been said so far.

If you suffer from ALS, integrate functional stimulation into your daily routine as early as possible.

A number of studies related to amyotrophic lateral sclerosis [ALS] show that treatments are successful when FES is used regularly. Recommended treatment time in mild cases is about 60 minutes per day, but depending on condition it can be several hours.

In return you can expect favorable results! You may ease coordination problems that make activities harder, reduce muscle weakness and stiffness, decrease pain, and delay progression (the advance of symptoms).