2Assistant Professor of Sport Physiology, Physical Education Department, Shiraz University, Shiraz, Iran
Background & Aims: Endothelin_1 secreted by endothelial cells has been identified as the strongest vascular constrictor. The aim of the present study was to investigate the role of concurrent training on plasma concentration of endothelin_1 and its relationship with blood pressure of old women. Methods: A total of 20 menopause women (Mean age: 67.47±5.92 years, mean body length: 152.92±7.52cm, mean weight: 65.83±11.83 kg, mean BMI 28.47±4.98 kg/m2 , fat percentage: 18.61±3.57, and WHR: 0.929±0.045) were selected purposefully and randomly assigned into the two groups of ten people. The experimental group did eight weeks of concurrent training in the form of three days per week each day two sessions resistance training with the intensity of 40 to 65% of one maximum repetition and with overload of 5% after each 6 sessions and aerobic training with 60 to 70% of maximum heart rate. Before and after eight weeks of exercise, the resting level of endothelin_1 and systolic and diastolic blood pressure were measured and recorded. Paired t-test was used for investigating the within group changes and independent t-test was used for investigating the between groups differences. Pearson correlation coefficient was used for investigating the relationship between endothelin_1 concentration and blood pressure. P<0.05 was considered as statistically significant level. Results: The results of this study showed that an 8-week concurrent exercise has a significant effect on decreasing endothelin_1 concentration (p=0.003), and also decreasing systolic (p=0.002) and diastolic (p=0.000) blood pressure of old women. There was a direct correlation between endothelin_1 level and systolic blood pressure (p=0.601). Nevertheless, there was no correlation between endothelin_1 level and diastolic blood pressure (r=0.352). Conclusion: Concerning the decrease of plasma endothelin_1 concentration and decrease of systolic and diastolic blood pressure following concurrent exercise, and concerning the relationship of endothelin_1 level and systolic blood pressure, it seems that one period of concurrent exercise with this intensity and volume can effect plasma endothelin_1 concentration as a risk factor for hypertension in old women.