Background & Aims: This study aimed to determine the pretreatment effect of 6 week swimming exercise with injections of vitamin D supplementation on the levels of Nerve Growth Factor (NGF) in female Lewis rats.

Materials & Methods: This experimental in vitro study that was conducted on female Lewis rats. In this study, animals were randomly divided into 9 groups (n=5 per group), including sham, EAE control, vitamin D healthy, EAE vitamin D, healthy swimming, EAE swimming, EAE combination and healthy combination. Swimming training program included one hour daily for 6 weeks and 5 days a week. In addition, supplementary groups received vitamin D supplementation (2ng/0.2mg sesame oil/every two days) intraperitoneally for 2 weeks. NGF levels were measured by ELISA.

Results: The results of this study indicated that NGF levels in each group of EAE vitamin D and EAE swimming significantly increased compared with control group (respectively P= 0.049, P= 0.006). Also NGF levels in EAE combination group significantly increased compared with control group (p=0.004). Furthermore, the weight of EAE vitamin D group, EAE swimming training group and EAE combination group increased compared with control that these only in EAE vitamin D group were not significant (respectively P= 0.164, P=0.001, P= 0.016).

Conclusion: From the results it can be concluded the factors effective in neuroprotection are pretreatment with medium-term training, swimming and injection of vitamin D, and increasing the levels of NGF. Hence, it seems that swimming is a good way to enhance the protection of nerve cells in the brain against MS risk factors and promotion of brain health.