People with central nervous system disorders such as spinal cord injury, stroke, cerebral palsy, Parkinson's disease, multiple sclerosis, etc… often have impaired lower extremity function that limits activities of daily life and independence. Different body-weight support systems have been developed to facilitate the rehabilitation process by compensating for the user's residual abilities. However, studies on weight-supported gait training on a treadmill have failed to show superiority over conventional rehabilitation programs for spinal cord injury and stroke. A recent study by the group around Grégoire Courtine showed that body-weight support systems that provide assistance only in the vertical direction disrupt the production of gait and balance, suggesting that current practices may even be detrimental for relearning to walk. For the past year, the Clinique Romande de Réadaptation (CRR) worked together with the G-Lab at EPFL and G-Therapeutics on a new robot platform specifically developed to provide adjustable trunk support along four independent degrees of freedom (LEAP). The investigators were able to draw on their long-term experience, which consists of different body weight support training systems for stroke and spinal cord injury. This knowledge, combined with the input of our therapists and physicians and the specific requirements for people with neurological/musculoskeletal disorders, has resulted in a design that can provide adjustable bodyweight support during over-ground locomotion, treadmill, stairs training, standing up and sitting down and for support during the training of activities of daily living.

The scope of this study is to examine how well the robot can be used for rehabilitation therapy in everyday clinical practice. This includes, among other things, technical aspects such as the handling of the hardware, the adaptability of the robot to the patient, and the safety during operation (such as the fall prevention). Various patient-specific aspects will also be evaluated e.g. comfort, positioning, or motivation of the patient. This study also aims to evaluate the software with the various support modes, operating options, and the user interface of the LEAP.

Healthy participants fulfilling all of the following inclusion criteria are eligible for the study:

• The healthy volunteer or legal representative has been informed and has signed the informed consent form
• Age 18-80 or age 5-10 (women or men)
• Weight below 137 kg
• Height between 120 and 190 cm
• Agree to comply in good faith with all conditions of the study and to attend all required training

Patients fulfilling all of the following inclusion criteria are eligible for the study:

• The patient has been informed and has signed the informed consent form
• Age 18-80 (women or men)
• Weight below 137 kg
• Height between 120 and 190 cm
• Neurological/musculoskeletal diagnoses
• Impairment of the lower extremities
• Stable medical and physical condition as considered by the attending doctor or physician
• Agree to comply in good faith with all conditions of the study and to attend all required training
• Other (non-neurological) diagnoses, who require intense training of the lower extremities
• The rehabilitation physician or doctor provides a final agreement whether the participant can train with the LEAP

The presence of any one of the following exclusion criteria will lead to exclusion of the participant, for example:

• Strong adipositas, which makes it not possible to adjust the harness to the anthropometrics of the participant
• Bracing of the spinal column.
• Severe joint contractures disabling or restricting lower limb movements
• Instabilities of bones or joints, fractures or osteoporosis/osteopenia
• Allergy against material of harness
• Open skin lesions
• Luxations or subluxations of joints that should be positioned in LEAP
• Strong pain
• Strong spontaneous movements like ataxia, dyskinesia, myoclonus*
• Instable vital functions like pulmonal or cardiovascular conditions
• Uncooperative or aggressive behaviour
• Severe cognitive deficits
• Inability to signal pain or discomfort
• Apraxia*
• Severe spasticity (Ashworth 4)
• Severe epilepsy*
• Insufficient head stability
• Infections requiring isolation of the patient
• History of significant autonomic dysreflexia
• Systemic malignant disorders
• Cardiovascular disorders restricting physical training
• Peripheral nerve disorders
• Other anatomic or co-morbid conditions that, in the investigator's opinion, could limit the patient's ability to participate in the study or to comply with follow-up requirements, or impact the scientific soundness of the study results.
• Known or suspected non-compliance, drug or alcohol abuse,
• Inability to follow the procedures of the study, e.g. due to language problems, psychological disorders, dementia, etc. of the participant,
• Participation in another study with investigational drug within the 30 days preceding and during the present study
• Previous enrolment into the current study Contraindications marked with an * are relative contraindications. Final approval needs to be obtained from the attending medical doctor.