Effect of Exercise on Arterial Stiffness: Is There a Ceiling Effect?

Area of Science:

• Cardiovascular Physiology
• Exercise Science
• Vascular Biology

Background:

• The impact of regular exercise on arterial stiffness in healthy individuals is unclear, with existing studies yielding conflicting results.
• Assessing arterial properties at discrete time points limits understanding of training-induced adaptations.
• This study aimed to elucidate the time course of changes in central arterial stiffness during an endurance training program.

Purpose of the Study:

• To determine the temporal adaptations of central arterial stiffness in response to a supervised endurance training intervention.
• To investigate changes in aorta characteristic impedance (Zc) and carotid distensibility (CD) over an 8-week training period.

Main Methods:

• Nine healthy, untrained adults underwent 8 weeks of supervised endurance training (ET) (3 sessions/week).
• Aorta characteristic impedance (Zc) and carotid distensibility (CD) were measured using ultrasonography at baseline and weeks 2, 4, and 8.
• Maximal oxygen consumption (VO2max) was assessed to evaluate changes in exercise capacity.

Main Results:

• VO2max significantly increased by 12% over 8 weeks of ET (P < 0.001).
• Systolic blood pressure increased by 7% (P = 0.019), and aorta Zc augmented by 38% (P = 0.003).
• Carotid distensibility showed a non-significant trend towards decrease (P = 0.196), despite a significant linear decreasing trend (P = 0.016).

Conclusions:

• Conventional endurance training, while enhancing aerobic capacity, led to an augmentation of central arterial stiffness in young, healthy individuals.
• These findings suggest that elastic arteries in healthy individuals may not become more compliant through standard exercise interventions.
• Arterial stiffness improvement through exercise might be contingent on the presence of pre-existing arterial impairment.