Immediate post-exercise blood pressure and arterial compliance in middle-aged and older normotensive females: A cross-sectional study

Carotid Arterial Compliance during Different Intensities of Submaximal Endurance Exercise

Background: The purpose of this investigation was to determine the elastic characteristics of the common carotid artery (CCA) during endurance exercise at 3 different intensities. Methods: Twenty young healthy participants (10 males and 10 females) participated in this quasi-experimental cross-sectional study. Participants were tested in two sessions: (1) we took resting measurements of the elastic characteristics of the CCA and performed a cardiopulmonary exercise test (CPET) on a cycle ergometer to determine submaximal exercise intensities, and we conducted (2) measurements of the elastic characteristics of the CCA while exercising in a cycle ergometer at 3 intensities based on blood lactate levels of low (<2 mmol/L), moderate (2-4 mmol/L), and high (>4 mmol/L). Beta stiffness was calculated using CCA diameters during systole and diastole, measured with high-definition ultrasound imaging, and CCA systolic and diastolic pressures were measured via applanation tonometry. Results: Overall, there were no differences between males and females in terms of any of the studied variables (p > 0.05). In addition, no significant changes were found in the CCA beta stiffness and vessel diameter (p > 0.05) between exercise intensities. There was a significant exercise intensity effect on CCA systolic pressure (p < 0.05), but not on CCA diastolic pressure (p > 0.05). Conclusions: The biomechanical characteristics of the CCA, determined via compliance and beta-stiffness, do not change during cyclical aerobic exercise, regardless of exercise intensity.

Impact of muscle echo intensity on post-exercise blood pressure response in older normotensive and hypertensive females: Pilot study

Exaggerated post-exercise blood pressure (BP) is considered a risk factor for the development of cardiovascular disease in older females. Muscle echo intensity (EI) using ultrasound can be used to evaluate intramuscular fat, one of the risk factors for cardiovascular disease. This study aimed to determine whether intramuscular fat assessed by muscle echo intensity is associated with the post-exercise BP response in older females. Ten older normotensive (SBP <130 mmHg, 71 ± 4 years), eight systolic BP-controlled (78 ± 4 years), and 17 hypertensive (SBP ≥130 mmHg, 74 ± 6 years) females were studied. After obtaining ultrasound images to assess the EI, participants performed ramp-up exercise until 50% maximal voluntary contraction (MVC: ~30-s; 3% MVC/s gradually increased knee extension force from 0% to 50% MVC followed by sustaining the force at 50% MVC for 10-s) and then five MVCs (~50 s; 10-s rest between each contraction). BP was measured before and immediately after exercise. Mean arterial pressure (MAP) pre- and post-exercise were significantly lower in normotensive and SBP-controlled, than in -uncontrolled hypertensive females (PRE: 85 ± 5 and 87 ± 7 vs. 106 ± 9; POST: 92 ± 8 and 94 ± 9 vs. 103 ± 11 mmHg, respectively, p < 0.05). EI was negatively correlated with ∆diastolic BP (∆DBP) but not ∆SBP and ∆MAP in normotensive females only (∆SBP, r = -0.21, p = 0.56; ∆DBP, R = -0.73, p = 0.02; ∆MAP, R = -0.49, p = 0.15). Greater intramuscular fat as indicated by higher EI is associated with less BP elevation immediately after exercise in older normotensive females. Greater intramuscular fat may lead to lower intramuscular pressure, resulting in less post-exercise BP elevation.

Immediate post-exercise blood pressure and arterial stiffness in hypertensive and normotensive older females

Although it has been suggested that increased arterial stiffness is linked to exaggerated blood pressure (BP) from brief moderate exercise, it is not clear whether this occurs in older adults with and without hypertension. This study investigates whether the immediate post‐exercise systolic BP following brief moderate exercise is associated with arterial stiffness in older females with different BP status. This cross‐sectional study included 191 older females aged 60–80 years without known cardiovascular disease (CVD). Arterial stiffness was determined by aortic pulse wave velocity (aPWV). Systolic BP was measured before and immediately following a 3‐min moderate walking test (stage 1 Bruce protocol). Specific quartile‐based thresholds were used to define an exaggerated immediate post‐exercise systolic BP for hypertensive and normotensive older females (quartile 4 as an exaggerated response). Traditional CVD risk factors were assessed (covariates). Older females from the highest quartile of immediate post‐exercise absolute systolic BP showed higher aPWV compared to their peers from the lowest quartile (β = .22 m/s, p = .018). The quartile‐based threshold to define the exaggerated post‐exercise systolic BP was higher in hypertensive than in normotensive older females (174 vs. 172 mmHg). In summary, exaggerated immediate post‐exercise systolic BP following a brief moderate exercise is associated with higher arterial stiffness in older females with different BP status.