BFS – also known as 'muscle fasciculation syndrome', 'benign fasciculation' and 'fasciculation syndrome' – is a disorder of the nervous system characterized by the uncontrolled twitching (fasciculation) of muscle groups in various parts of the body. It may or may not be associated with muscle cramps. Although it occurs more commonly in the muscles of the legs, arms and face, it can occur in any voluntary muscles, including those of the tongue. As its name suggests, it is a benign, somewhat irksome condition that, fortunately, does not progress to a more serious neurological disorder.

The fasciculation may be localized – a twitching eyelid for instance – or become far more extensive and involve several limbs or even the abdominal muscles. They may be either intermittent or continuous; in fact most people will experience a degree of BFS at sometime in their lives without realizing that they have this condition. For example, a simple facial 'tic' is a localized fasciculation.

However, most individuals will only be aware of the diagnosis of BFS when the symptoms become so widespread and persistent that they seek medical advice.

A more serious disease called amyotrophic lateral sclerosis (ALS) - also known as Lou Gehrig's disease also has muscle fasciculation as a dominant symptom. Although fasciculation is a feature of both BFS and ALS that of the former usually ceases when the affected muscle is exercised while the twitching in ALS patients persists whether the muscles are working or at rest. A full neurological examination and electromyography (EMG) are all that are needed to make a diagnosis of BFS and exclude more serious neurological diseases.

Although the precise cause of BFS is unknown it may be associated with several factors including acute viral illnesses, exercise, anxiety or drugs. Some authorities have suggested that insecticides could also be a causative factor as muscle fasciculation is one of the prominent symptoms seen in organophosphate poisoning.

Exercise triggers muscle twitching in the majority of BFS patients that and is probably related to the higher than normal amounts of free radicals that are released by the body during prolonged exertion.

Free radicals are a by-product of the cell's energy production therefore the longer and more intensely an individual exercises the more free radicals his body will produce. For this reason endurance athletes are subject to free radical overload and oxidative stress. If prolonged exercise is associated with BFS, in all likelihood the cause of the twitching is free radical-induced nerve and muscle excitability.

Although there are no recognized drugs for the treatment of BFS, anecdotal reports suggest that some individuals benefit from either pharmaceutical or natural sedatives. However no clinical trials have been done to show whether or not these products are more effective than placebos.

As prolonged physical activity produces large quantities of free radicals and exercise is such a strong precipitating factor for BFS, oxidative stress is almost certainly one of the underlying pathological factors contributing to this condition.

Therefore it is not surprising to find that there is reliable anecdotal evidence that antioxidant-rich food supplements are effective in treating this annoying, and often distressing, condition.

It is also possible that even those individuals who do not suffer from exercise induced BFS may be under oxidative stress for other reasons and could reduce their symptoms by increasing their daily antioxidant intake.