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Introduction: Physical activity increases serum levels of brain-derived neurotrophic factor (BDNF) in patients with Multiple Sclerosis (MS); however, the effect of learning a skill using mental imagery in the PETTLEP model and comparing its effectiveness with physical activity in the levels of this factor has not been investigated so far. This study aimed to compare the learning of a skill through PETTLEP imagery and physical training. Moreover, it was attempted to investigate the effect of the combination of these two methods on BDNF levels and memory function in MS patients.
 
Materials & Methods: In total, 30 women with MS and a mean age of 37.5±3.02 years Expanded Disability Status Scale (EDSS)=0-2 were included in this study. Based on Kim Karad visual memory test scores, they were divided into three homogeneous groups of 10 subjects per group. The groups included PETTLEP imagery, physical activity, and combined physical training and PETTLEP imagery. Before the intervention, visual memory was assessed using the Kim Karad visual memory test, and BDNF serum concentration by blood sampling method. The groups were subjected to three 30-min sessions weekly (for six weeks). After the intervention, the research variables were reevaluated at the posttest stage. Ethics code: IR.SSRC.REC.1397.012  
 
Findings: The result of one-way ANOVA showed that the combination of PETTLEP imagery exercises and physical training, compared to physical training and imagery alone, increased BDNF levels (P=0.026 and P≤0.0005, respectively). However, imagery training improved memory performance in the short term and long-term memory, compared to physical training (P=0.009 and P=0.034) or combined exercise (P≥0.05).
 
Discussions & Conclusions: Combination of physical training and imagery is effective in the rehabilitation of MS patients, and it can be used as a non-pharmacological method in this regard.