McArdle disease is a genetic glycogen storage disease characterised by impaired muscle metabolism. Although typical clinical features such as physical activity intolerance, muscle pain, cramps and weakness and second wind phenomenon can be identified through careful history taking, delay in diagnosis is still a common problem. This article aims to support timely diagnosis by highlighting the classic anamnestic and clinical features of the disease. Additionally, it provides impulses for structured and continuous medical care for people with a chronic illness.