## 1 Introduction  
Strokes are a significant public health issue, being one of the most common causes of death and often leading to permanent disability and impairment [1, 2, 3]. It is estimated that there are currently 9.53 million prevalent stroke cases in the European Union. By 2047, the number of prevalent stroke cases is expected to increase by more than a fourth, reaching over 12 million [3]. This increase is related to the aging of the population of the European Union, as age is one of the most significant risk factors for stroke [2, 4].  
A key aspect in counteracting the disabling effects of strokes is the initiation of early and comprehensive rehabilitation. Neurological rehabilitation of stroke patients is typically conducted based on activities such as kinesitherapy and therapy using specialized methods like NDT Bobath or PNF [5, 6, 7]. It also includes hand therapy, balance training, gait re-education, and occupational therapy (particularly self-care training and improving the ability to perform activities of daily living) [8]. All these elements should be introduced as early as the patient's condition allows because, in the case of a stroke, we refer to the concept of a \"therapeutic window\", denoting the period during which therapy has the highest likelihood of achieving the best outcome [7]. This is related to the intense course of neuroplasticity processes in the early period after a stroke. Neuroplasticity is a phenomenon that allows the recovery of functions lost by the brain. It is based on the restoration of connections between nerve cells that were lost due to damage (e.g., as a result of a stroke or a traumatic brain injury) [9; 10]. This phenomenon involves a range of both intracellular and extracellular mechanisms that enable the brain's self-repair and reorganization, allowing it to regain functions lost due to damage most effectively [11].  
Promoting neuroplasticity in neurological rehabilitation is mainly achieved through appropriate exercises that engage or stimulate the patient's motor system, allowing for the restoration of lost motor functions. However, in recent years, additional methods that may influence neuroplasticity and increase the effectiveness of rehabilitation have been explored [12; 13]. Some of these methods involve using physical stimuli to enhance neuroplasticity processes.  
In recent years, Repetitive Transcranial Magnetic Stimulation (rTMS) has gained significant popularity in the treatment of stroke patients [13; 14]. Additionally, reports suggest that not only rTMS but also the application of Extremely Low-Frequency Magnetic Fields Therapy (ELF-MFs) may be useful in the treatment of neurological patients [12; 13; 15]. ELF-MFs could, therefore, be a therapy that, by supporting neuroplasticity, enhances the effectiveness of traditional physiotherapeutic methods in the rehabilitation of stroke patients.  
The literature describes two areas for the application of this type of stimulation: the head and the pelvic region [13]. Some authors suggest that application to the head may induce epileptic seizures [12]; however, according to the available literature, no data support this [13; 16]. Moreover, one study claims the safety of ELF-MF stimulation in the head area [16]. Therefore, an assessment of potential differences in the effectiveness of magnetic field application to the head versus the pelvic region in stroke patients is needed. However, due to uncertainties regarding the safety of this type of therapy, conducting such a study should be preceded by safety and feasibility studies. Thus, this pilot study aimed to assess the feasibility of the study, as well as the safety of the procedure.