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GSD5 – MCARDLE DISEASE

Also known as muscle phosphorylase (or myophosphorylase) deficiency, McArdle disease was the first discovered metabolic myopathy.
SYMPTOMS

Muscle pain and fatigue on everyday activity and exercise. Fixed contracture with rhabdomyolysis. Raised baseline CK.

SECONDARY

Raised urate level, possible muscle wasting.

ONSET

Childhood.

INVOLVED

Skeletal muscle.

TREATMENT

No specific treatment. Maintain healthy diet, control weight, take gentle aerobic exercise.

OUTLOOK

Good with gentle aerobic exercise and only very brief anaerobic or isometric activity.

First described in a paper by Dr. Brian McArdle in 1951, McArdle disease is a rare metabolic disorder which causes muscle fatigue, cramping, and pain in everyday activities and exercise. If activity is prolonged despite these warnings, then muscle damage ensues, with the risk of muscle breakdown (rhabdomyolysis) and possible kidney failure.

MANY HAVE DELAYED DIAGNOSIS

Symptoms are usually apparent during the first decade of life, but many people do not manage to obtain a diagnosis until the third or fourth decade. Later in life some people with McArdle disease experience fixed muscle weakness, possibly from cumulative muscle damage or from muscle wasting due to avoidance of activity.

 

REGULAR ACTIVITY & EXERCISE

It is important for those with McArdle disease to regularly engage in aerobic exercise such as walking. At least 150 minutes per week is advised. It is just as important to avoid more than very brief isometric (static) and anaerobic activities such as lifting heavy weights or sprinting.

ADAPT AND BOOST AEROBIC FITNESS

It is a major advantage to be diagnosed early and to be given the correct advice. Learning to adapt activities, maintaining aerobic fitness, and keeping weight under control can have a very significant beneficial impact on long-term outcomes.

EMERGENCY INFORMATION?
ONE CLICK TO READ FREE ON-LINE!

Two books to help you manage well.

Tips on the “Dos” and “Don’t”s of managing McArdle‘s.

See the contents list in each publication.

Detailed guidance on understanding and improving your condition.

ONE CLICK TO VIEW HERE!

Four minutes on personal experiences of joining a walking course.

ONE CLICK TO READ HERE!