Locomotor Muscle Oxygenation and Activation During Acute Interval Compared to Constant-load Bed-cycling Exercise

Up to 60% of patients admitted to the Intensive Care Unit (ICU) with a prolonged stay in the ICU develop complications such as intensive care unit acquired weakness (ICUAW) characterized by limb and respiratory muscle weakness. ICUAW is associated with worse prognosis, longer ICU stay and increased morbidity and mortality. Physical therapy (PT) interventions in the intensive care unit (ICU), can improve patients' outcomes. However, improvements in muscle function achieved with standard physical activity interventions aiming at early mobilization are highly variable due to lack of consistency in definition of the interventions, lack of consideration for the complexity of exercise dose and/or insufficient stimulation of muscles during interventions. It has been suggested that modifying early mobilization and exercise protocols towards shorter intervals consisting of higher intensity exercises might result in more optimal stimulation of muscles. In the present study the researchers therefore aim to simultaneously assess (by non-invasive technologies) locomotor muscle oxygenation and activation along with the measurements of the load imposed on respiration and circulation during two different training modalities i.e., moderate intensity continuous bed-cycling (endurance training) vs high-intensity alternated by lower intensity periods of bed-cycling (interval training).