As the critical care practice has improved over the last decades more patients are recovering from intensive care therapy. However, muscle atrophy and neuromuscular dysfunction are commonly observed sequelae after critical illness and are thought to play important roles in the development of intensive care unit acquired weakness (ICUAW). As a consequence, these entities may contribute to the impaired physical function and prolonged convalescence reported by ICU patients up to twelve months after discharge. Thus, strategies to counteract muscle atrophy and neuromuscular dysfunction acquired during the ICU stay may therefore potentially improve physical outcome and reduce the overall burden of critical illness. Limited information is available on muscle function in ICU patients and to our knowledge no muscle stimulation methods are currently available for evaluating muscle fatigue in large, proximal muscles groups, such as m. quadriceps, in non-cooperating ICU patients.