Comparison of changes in miR-146a gene expression and serum levels of TNF-α, IL-6 and CRP following interval or continuous aerobic training with calorie restriction in obese women

Micro-RNAs (miRNA) are short RNA molecules that as significant regulators of physiological processes associated with obesity play important roles in body; this is while the combination of effect of interval and continuous aerobic training along with calorie restriction can affect the gene expression of miR-146a and some inflammatory factors like tumor necrosis factor- α (TNF-α), interleukin -6 (IL-6) and C-reactive protein (CRP). Therefore, the aim of the present study was to determine the effect of two types of exercise training along with intermittent calorie restriction (ICR) on miR-146a expression and TNF-α, IL-6 and CRP levels in obese women.

Twenty-eight women were selected by targeted sampling from obese women aged 35-45 years in Tabriz city and were divided randomly into four groups including of ICR (ICR, 20 percent), high intensity interval training and ICR (10 percent calorie restriction from exercise and 10 percent ICR), a combination of continuous aerobic training and ICR (10 percent calorie restriction from exercise and 10 percent ICR) and control groups. Interval training (up to 75-95% of the maximum reserve heart rate) and continuous training (up to 60-75% of the maximum reserve heart rate) was performed for 8 weeks with repetition of 3 sessions per week. Dependent variables were measured before the intervention and 72 hours after the last training session. Results were extracted using Shapiro-Wilk, repeated measure analysis of variance and Bonferroni tests at the significance level of p<0.05.

Both training groups with calorie restriction compared to the control group showed a significant increase in maximal oxygen uptake and miR-146a expression and a significant decrease in TNF-α, IL-6 and CRP (p<0.05). While, there was no significant difference between the two groups of interval and continuous aerobic exercise with calorie restriction (p<0.05.)

Doing exercise (regardless of whether it is interval or continuous) and limiting daily calorie intake can be effective in reducing chronic inflammation in obese people and can be used as a non-pharmacological method to help solve the problems of these people.