Background: Aging induces structural and functional changes in the heart that are associated with increased risk of cardiovascular disease and impaired functional capacity in the elderly. However, physiological changes at the starting of exercise and during recovery phase have not been evaluated at all. Six-minutes walk distance (6MWD) test assess exercise tolerance and cardiovascular responses during training. This study is focused to quantify hemodynamic profile to compare dynamic cardiovascular profile during a six-minute walk in elderly and young participants.
Materials and Methods: The database was composed of two groups of 46 normotensive subjects: young (20 to 40 years, n=23) and elderly (60 to 80 years, n=23). There were no differences of gender between young and elderly groups. Beat-to-beat blood pressure and pulse were measured by Finapres during six-minute walk distance test: a first phase of rest with a duration of 3 minutes (pre-exercise), a second phase, with a duration of 6 minutes, in which patients are doing the exercise and the third phase with a duration of 3 minutes (recovery and post-exercise phases). An average of systolic and diastolic blood pressures and overall heart rate were determined.
Results: Differences in blood pressure and heart rate and the regularity were found between age groups. Moreover, systolic blood pressure showed differences in all the phases in the female gender, for instance during the exercise phase 118,50±20,60 in the young women vs. 163,87±20,86 in older adult women (p<0.001). Moreover, the activation time differences during the recovery phase, were statistically significant, with higher values in the older adults, 71,54±11,13 ms. 62,26±13,24 ms. in young adults group (p=0.016).
Conclusion: In summary, our results suggest that hemodynamic measurements provide complementary information that can be very helpful to characterize aging cardiac dynamic.