The effect of a resistance training course with citrulline malate supplementation on resting serum BDNF, nitric oxide and estrogen levels in postmenopausal women

Exercise training is a non-pharmacological method that is effective in reducing postmenopausal complications; citrulline is also an effective supplement for exercise performance. The purpose of this study was to investigate the effect of eight weeks of resistance training and citrulline malate supplementation on resting levels of BDNF, NO and estrogen in postmenopausal women.

In the present quasi-experimental research, 42 postmenopausal women were divided into six groups including: Exercise + Supplement, Exercise + Placebo, Exercise, control, Supplement and Placebo. Resistance training was performed for eight weeks, three sessions per week at intensity of 45-55% of 1 repetition of maximum. Supplementation consisted of 200 ml of water, 8 g of citrulline malate, 20 ml of lemon juice and 10 g of sugar one hour before the training session. Data were analyzed by two-way ANOVA and dependent t-test at the significant level (P < 0.05).

Increase in estrogen, NO and BDNF was significantly higher in exercise + supplement group than in exercise and supplement groups (P <0.001). Also, there was a significant increase in estrogen in the exercise group compared to the supplement group (P < 0.001), but there was no difference between NO and BDNF levels in the exercise and supplement groups.

According to the results both resistance training and supplement citrulline malate had an effective methods for increasing serum levels of estrogen, NO and BDNF in postmenopausal women, and combining both methods has more effect on the improvement of these variables than either method alone.