Effects of preconditioning or following exercise on brain-derived neurotrophic factor (BDNF): A systematic review in animal models of multiple sclerosis‏

Brain-derived neurotrophic factor (BDNF) plays a vital role in the brain. On the other hand, researchers showed that exercise may cause more release of BDNF and thus have a positive effect on the brain. Studies have reported controversial findings in multiple sclerosis, and there are no broad conclusions on this topic. This study aims to systematically investigate the effect of exercise training on BDNF concentration in multiple sclerosis animal models. Searches were conducted in the electronic databases of PubMed, Scopus, Medline, Cochrane Library and Google Scholar search engine to obtain the related articles about the role of exercise training on BDNF levels just in animal models of multiple sclerosis. All of the database searches were limited to the period from inception to February 2021. Two reviewers extracted study details and data. The methodological quality of the studies that used animal models was assessed using the PEDro Scale. Fourteen articles were included in this review with scores from 7/10 to 8/10 according to the PEDro scale. Five articles reported elevation, one article reported a reduction; and eight articles reported no changes in BDNF level following or preconditioning exercise training in model of multiple sclerosis. The findings of this study showed that aerobic exercise increases changes in central BDNF concentration in multiple sclerosis in animal model

The Effect of Two Kinds of Aerobic Exercise on the Static and Dynamic Balance of Old Men

Objectives: The aim of present study is to determine the effect of two methods of aerobic training on static and dynamic balance in old men.  Methods & Materials: 37 aged people over 60 years old who were physically healthy divided into three groups after randomly carrying out pretest: 1) walking or running aerobic exercise group (n=12), 2) cycling aerobic exercise group (n=13) and 3) control group (n=12). Then groups 1 and 2, participated in running or walking exercise and cycling aerobic exercise as well with 60 percent of maximum heartbeat intensity. These two groups who were considered experimental groups of research appeared on exam site for 8 weeks, each week 3 sessions and each session 45 minutes. They rested one day between every two sessions of exercise. During the project group 3 (control) continued its daily activities and had no especial exercise. After the training period, all subjects participated in the posttest session. In order to measure the static and dynamic balance Sharpend Romberg test and balancing timber test were used. The covariance analysis test (ANCOVA) was also applied to examine the effect of exercise on the dependent variables and to study differences between group.  Results: The findings showed that exercise training programs in both experimental groups in research compared with control group significantly improved static and dynamic balance of subjects. It was also showed that the development of the first group (walking or running exercise group) in both static and dynamic balance test was significantly higher than Group 2 (bike exercise group).  Conclusion: According to the results, it is recommended that trainers, organizations and institutions that deal with the elderly, use the cycling and walking exercises, especially walking and jogging to reduce the risk of further problem in these people