Muscle relaxants are an integral part of today's anesthesia. They improve intubating conditions and reduce doses of other substances needed for general anesthesia. For ensuring patient safety, neuromuscular function is monitored during general anesthesia. The latter one is only terminated, when neuromuscular monitoring shows an objective normal value. Despite this accurate surveillance, a lot of patients complain about subjectively uncomfortable muscle weakness in the recovery room. A possible explanation for this ostensive contradiction can be the variable "margin of safety" of neuromuscluar transmission in different muscle groups. Waud et al describe this phenomenon, as the fact, that neuromuscular transmission is only clinically detectable, when a certain number of post-synaptic receptors is not blocked. The necessary fraction of free receptors differs a lot between the muscle groups (15-50%). As neuromuscular monitoring only measures one muscle group exemplarily, and a clinically non-detectable number of post-synaptic receptors can be blocked shortly after anesthesia, the subjective muscle weakness of patients could need treatment.