ABSTRACT
Objective To investigate acute effects of anaerobic exercises by a bicycle ergometer on arterial elastic modulus and local hemodynamics in human common carotid arteries with different genders. Methods Nine male and eight female healthy young volunteers at the age of 20-30 year-old successively underwent four groups of exercise trainings with the same workload by an anaerobic bicycle ergometer. The waveforms of arterial diameter and center-line blood velocity were measured in the right common carotid artery using a color Ultrasonic Doppler for each group when at rest and right after exercise training. The heart rate, systolic and diastolic blood pressures were simultaneously measured in brachial artery using an automatic electronic sphygmomanometer. All the measured data were analyzed based upon the principle of classic hemodynamics. The arterial elastic modulus and local hemodynamic parameters, including pressure-strain elastic modulus, flow rate, circumferential strain, wall shear stress and oscillatory shear index (OSI), were then calculated. Results The heart rate and arterial elastic modulus increased after exercises; with the accumulative exercises, in one cardiac cycle, the maximum and mean center-line velocity and flow rate increased while the minimum velocity and flow rate decreased; the systolic and mean blood pressure increased while diastolic blood pressure exhibited no significant change; no significant change could be found in the circumferential strain; the maximum and mean shear stress increased significantly while the minimum shear stress reduced; the oscillatory shear index also increased. Conclusions The anaerobic exercises by a bicycle ergometer may increase the arterial elastic modulus and induce significant effects on local hemodynamic parameters in common carotid arteries for young volunteers with different genders at the age of 20 30 year old. The results in this study could provide useful hemodynamic information for regulation of cerebrovascular function by anaerobic exercises.