An alternation in arterial compliance associated with elevated aerobic fitness☆

Abstract 

Objective: To identify a nonpharmacologic method of enhancing arterial compliance, a correlate of atherogenesis; to determine the relationship between aerobic fitness levels and arterial compliance; and to identify a characteristic Doppler analog waveform associated with elevated levels of aerobic fitness. Design: A cross-sectional design was used to compare the Doppler studies of sedentary subjects and aerobically trained subjects. The trained subjects were divided into a moderately trained group and a highly trained group. Setting and Participants: One hundred subjects consisting of 50 sedentary control subjects and 50 aerobically trained subjects in a university-based setting. The mean age of the total group of subjects was 36.0 ± 8.6 years. Each group had an equal number of male and female subjects. Control subjects were sedentary, with normal vascular risk factor profiles and a mean aerobic capacity (maximum oxygen consumption) of 25.8 ± 3.0 mL · kg⁻¹ · min⁻¹. Trained subjects were divided into a moderately trained group and a highly trained group. The mean aerobic capacity for the moderately trained group was 46.0 ± 4.4 mL · kg⁻¹ · min⁻¹, and that for the highly trained group was 63.3 ± 6.7 mL · kg⁻¹ · min⁻¹. A standard Doppler examination, including ankle pressure index was performed on each subject. Main Outcome Measure: Arterial compliance measurements were recorded by using A-mode Doppler ultrasonography and analyzed by diastolic flow analysis. Results: Control subjects had a mean arterial compliance level of 21.1% ± 2.5%. The moderately trained subjects had a mean compliance level of 34.8% ± 4.9%, and the highly trained subjects had a mean compliance level of 46.0% ± 6.7%. An analysis of variance was used for this comparison and was significant at a P value of less than .01. Conclusion: These results demonstrate that elevated aerobic fitness levels are associated with an augmentation in arterial compliance. A linear relationship existed in our data between aerobic fitness levels and arterial compliance. This study suggests that enhanced arterial compliance is another beneficial cardioprotective effect associated with aerobic training. (J Manipulative Physiol Ther 2000;23:27–31)

Keywords:  Aerobic Exercise, Doppler Ultrasound