Patients in intensive care often develop acquired muscle weakness (ICUAW or Intensive Care Unit Acquired Weakness) due to immobilization and muscle atrophy. Early mobilization can help reduce weakness and improve functional recovery, but practices vary. Muscle strength assessment, particularly using the MRC (Medical Research Council) score, is crucial, though it has precision limitations. Additional methods, such as manual dynamometry and functional scales, are needed to better track muscle recovery. The quadriceps, important for function, requires early evaluation, but there is a lack of specific data in intensive care to predict medium-term functional recovery.