Progressive resistance training without volume increases does not alter arterial stiffness and aortic wave reflection

Area of Science:

• Cardiovascular Physiology
• Exercise Science
• Vascular Biology

Background:

• Endurance exercise effectively reduces arterial stiffness.
• The impact of resistance training (RT) on arterial stiffening remains debated, with some studies showing increased stiffness in young adults following high-volume RT.
• Progressive overload is a key principle in RT, but its effect on vascular health needs clarification.

Purpose of the Study:

• To test the hypothesis that a resistance training protocol emphasizing progressively higher intensity without increasing training volume does not elevate central or peripheral arterial stiffness.
• To determine if such a protocol alters aortic pressure wave reflection in young men and women.
• To investigate the effects on vascular function markers and body composition.

Main Methods:

• A 12-week randomized controlled trial involving young adults (n=24 RT group, n=18 control group).
• The RT group performed 2 sets of 8-12 repetitions to volitional fatigue, 3 days/week, using progressively higher intensity.
• Measurements included pulse wave velocity (PWV), augmentation index (AIx), flow-mediated dilation (FMD), plasma nitrate/nitrite (NOx), norepinephrine (NE), and body composition.

Main Results:

• RT significantly increased one-repetition maximum strength, lean body mass, and reduced body fat percentage.
• No significant changes were observed in central (carotid-femoral) or peripheral (carotid-radial, femoral-distal) PWV.
• Aortic pressure wave reflection (AIx) and brachial FMD remained unchanged, as did plasma NOx and NE levels.

Conclusions:

• A resistance training protocol focused on increasing intensity without concurrent volume increases does not induce arterial stiffening in young adults.
• This RT approach does not negatively impact aortic pressure wave characteristics or vascular endothelial function.
• The findings suggest that RT can be safely implemented to improve strength and body composition without compromising arterial health in young individuals.