High Intensity Interval Training in Chronic Stroke Patients

Stroke is a global health-care problem that is common, serious and disabling. In most countries, stroke is second or third most common cause of death and one of the main causes of acquired adult disability. After stroke, patients remain at continued high risk for recurrent stroke as well as for myocardial infarction and cardiac death. After completion of conventional physical therapy, there are no empiric recommendations and few resources promoting regular exercise during the chronic stroke period.Interventions to improve cardiorespiratory fitness are still not part of routine neurorehabilitation programs in many rehabilitation centers, and therapy is often dominated by standard rehabilitative therapies based on neurodevelopmental principles such as the Bobath concept. These standard therapies are an insufficient stimulus to increase fitness levels after stroke.

Stroke is a major cause of chronic disability worldwide. After stroke, patients remain at continued high risk for recurrent stroke as well as for myocardial infarction and cardiac death. Comorbid cardiovascular conditions are present in 75% of stroke patients, representing the leading cause of death in stroke survivors. Due to the low levels of physical activity, stroke survivors are deconditioned, leading to a loss of functional and social independence with subsequent declines in quality of life. Interventions to improve cardiorespiratory fitness are still not part of routine neurorehabilitation programs in many rehabilitation centers, and therapy is often dominated by standard rehabilitative therapies based on neurodevelopmental principles such as the Bobath concept. These standard therapies are an insufficient stimulus to increase fitness levels after stroke.

The first aim of the study is to evaluate the effects of a high intensitive physical training in improving cardiorespiratory fitness and gait ability in chronic stroke patients. The second aim is to compare the effects of high aerobic interval treadmill training and maximal strength training in chronic stroke patients.

Patients will be randomized into three groups. The first group (experimental group) will be subjected to 3-month training period (3 sessions/week) of high intensity aerobic training on treadmill. The second group (experimental group group) will undergo to a strength training with the same duration and frequency of the first group. The third group (control group)will be subjected to conventional training with the same duration and frequency of the experimental groups. Data will be analysed by means parametric and non-parametric tests. Both, within and between groups comparison will be performed.

As primary outcomes measures will be considered the peak oxygen uptake, walking energy cost, 6 minutes walking test. As secondary outcomes measures will be considered the 10-meter Walking Test,Time Up and Go test, Activities- specific balance confidence scale, SF-36 Health Survey Questionnaire, Stroke Impact Scale, Oxygen Uptake Efficiency Slope (OUES), arterial-venous oxygen difference; cardiac output and muscle strength.

Eligibility Criteria:
Inclusion Criteria:

* Diagnosis of ischemical brain injury or intracerebral hemorrhage by MRI or computed tomography at least 6 months before the onset of the study;
* Ability to walk in the treadmill at \>0.3 km/h for 3 minutes handrail support;
* Be able to give informed consent and be motivated to participate in 3- month intensive physical fitness training.

Exclusion Criteria:

* Mini Mental State Examination \<20;
* Unstable angina pectoris;
* Unstable cardiac conditions;
* Complex ventricular arrhythmia;
* Resting systolic blood pressure \>200 mm/Hg - Resting diastolic blood pressure \>100 mm/Hg;
* Aphasia (unable to follow two commands);
* Other medical conditions precluding participation in aerobic exercise.