Patient description: The patient is a 55 year old man visiting his primary care physician for lower urinary tract symptoms including frequency, urgency, weak stream, incomplete emptying and intermittent flow for the past 9 months. Further evaluation revealed: IPSS score : 15 Post-void residual: 70 mL Prostate volume (TRUS): 60 mL Prostate-specific antigen (PSA) level: 3.2 ng/mL 10 mL/sec of maximum flow rate when urine volume was 130 mL He is otherwise healthy only using Vit D 1000 units daily. His recent blood chemistry (3 days ago) was normal: Hgb: 13.5 g/dl WBC: 135000 /mm3 Plt: 350000 /ml PT: 11 second PTT: 35 second INR: 0.9 Creatinine: 0.5 mg/dl BUN: 10 mg/dl U/A: Color: yellow Appearance: cloudy PH: 5.3 Specific gravity: 1.010 Glc: 100 Nitrite: negative Ketone: none Leukocyte esterase: negative RBC: negative WBC: 2 WBCs/hpf U/C: negative

Clinical trial eligibility criteria: eligible ages (years): 18.0-90.0,  Muscle Weakness Patients will be recruited in the Intensive Care Unit of the Royal Liverpool University Hospital. All patients will be over 18, and have a critical illness that requires mechanical ventilation with an initial period of sedation. This study will focus on patients with a definite or suspected case of sepsis from any source. Sepsis has been recently redefined as: "Life threatening organ-dysfunction caused by dysregulated host response to infection" whilst septic shock has become a subset of sepsis, defined as: "circulatory and cellular/metabolic dysfunction associated with a higher risk of mortality(44). For the purposes of this study, a patient will be regarded as septic if they have evidence of infection-related organ failure (e.g. sepsis-associated coagulopathy, altered mental state, cardiovascular dysfunction, acute kidney injury, and altered liver function) and require invasive mechanical ventilation with either definite or suspected evidence of infection. This is to allow prompt treatment with FES rather than waiting for a positive microbiological result to be obtained. Within the definition of sepsis "from any source" a list of following is illustrative but not exhaustive Urogenital sepsis (including urosepsis, pyelonephritis, endometritis and chorioamnionitis) Pneumonia (including community acquired, hospital acquired, and aspiration pneumonia. Ventilator associated pneumonia would be excluded.) Neurological infections such as encephalitis and meningitis Cellulitis, osteomyelitis and infections of soft tissue NOT affecting the lower limb Surgical infections, including post-operative laparotomy with evidence of peritoneal soiling, and evidence of infection prior to the operation, in patients who require 2 or more organ system support after the operation Intra-abdominal sepsis, including biliary sepsis, hepatitis, and acute pancreatitis. In the case of acute pancreatitis, evidence of infection is required to fulfil the criteria. Acute pancreatitis with sterile tissue/fluid samples would not be suitable  Patients under 18 Patients who decline consent Pregnancy Neuromuscular disease Rhabdomyolysis Lower limb trauma Patients unlikely to survive to 96 hours post admission Consent unobtainable within 48 hours of admission Morbid obesity (BMI>40) Presence of a pacemaker or Implantable Cardiac Defibrillator (ICD)