An experimental study will be carried out to examine how a manual therapy protocol can influence a series of parameters related to motor and non-motor symptoms in patients who have Parkinson's disease / Parkinsonism. To do this, an intervention will be carried out that will last a minimum of 6 weeks. In addition to their ongoing treatment, the study subjects will receive a maximum of 2 sessions of manual therapy each week. They will undergo a series of measurements both before and after the intervention related to gait, balance, non-motor symptoms, and some more specific parameters of gait. The study's main objective is to obtain information about possible treatment models based on manual therapy for Parkinson's disease. It is also hoped to compile a series of results that will lead to conclusions and benefit the development of physiotherapy for this disease. It is also hoped that this will help those affected so that the treatment is as comprehensive as possible and that the physiotherapist can use as many tools as are available to them to address the pathology.