###### Abstract  
Multiple sclerosis is a prevalent neurodegenerative disease that significantly affects gait and exercise capacity. The core system is involved in providing sufficient spinal stability for dealing with stability demands. People with multiple sclerosis exhibit reduced trunk stability, which may affect stability during tasks such as reaching, stepping, and unexpected perturbations. This systematic review aimed to evaluate the effects of core training on gait and exercise capacity in people with multiple sclerosis. A systematic review was conducted in the databases PubMed/Medline, Web of Science (WOS), ScienceDirect, CINAHL, Scopus, and Physiotherapy Evidence Database (PEDro). Randomized controlled trials up to January 2025 included the following PICO inclusion criteria: (Participants) adults with a multiple sclerosis diagnosis; (Intervention) a core stability training program (alone or combined with another intervention); (Comparison) compared to no intervention, placebo or any other intervention; (Outcomes) and including at least one outcome related to gait and/or exercise capacity. The search identified 781 records, and finally 12 studies were included in this review. Methodological quality and risk of bias were assessed using the PEDro scale (with 8 as the median score) and the Cochrane risk assessment tool (ROB2), showing in most cases some concerns, particularly regarding outcome selection. Most of the studies included reported significant improvements in gait assessed with the timed up and go, timed 25-foot walk, and six spot step tests. Also, the results of exercise capacity assessed with the 6 min and 2-min walk test significantly increased in most of the studies. The reviewed articles suggest that a core-based exercise program may be effective in improving gait and exercise capacity in people with multiple sclerosis. However, considering the heterogeneity of the interventions, results, population, and the high risk of bias of some trials, more research is needed to validate these preliminary results. core exercise training; exercise therapy; multiple sclerosis; neurorehabilitation; quality of life +
Footnote †: journal:prevent relapses, or partially reverse disability. However, non-pharmacological interventions, such as physical exercise, have also proven beneficial in improving both physical and mental functional capacities in people with MS [4; 5]. Physical exercise may include Pilates, yoga, aerobic training, resistance training, aquatic therapy, virtual reality training, or whole-body vibration training [5]. MS presents considerable heterogeneity in both symptom manifestation and clinical progression [6]. Fatigue, one of the most common symptoms, affects up to 80% of people with MS. It is typically perceived as a lack of physical and/or mental energy that interferes with daily activities and may be associated with reduced activity levels [4]. A recent study has shown that the cerebellum is involved in MS-related fatigue, including physical cognitive, and psychosocial domains, as well as in overall clinical disability [6]. Gait impairment and exercise capacity are also common among individuals with MS [7]. Gait is significantly affected at both self-selected and increased pace across all stages of the disease, with more pronounced deficits in advanced stages [8]. Common gait abnormalities include muscle weakness, spasticity, imbalance, and reduced walking speed [2; 9]. Exercise capacity, defined as the maximum amount of physical exertion a person can sustain, is closely linked to cardiovascular and respiratory function [10]. A previous study reported that individuals with MS exhibited significantly higher heart rates during exercise and covered shorter distances compared to healthy controls. The reduced performance in the Six-Minute Walk Test (6 MWT) was attributed to limitations in ADL, elevated resting heart rate, and fatigue [11].