The Relationship Between Arterial Stiffness and Resistance Training

Effects of different training modes on hemodynamics and vascular endothelial function in young obese adults

Comparing the effects of 8 weeks of aerobic (AE) and resistance exercise (RE) on cardiovascular function in obese young adults. Exploring the mechanisms of resistance exercise on cardiovascular function. 44 subjects (22.4 ± 2.7 years, female/male: 26/18) were randomly divided into the AE and RE group. AE group performed platform running with 70-75% heart rate max. RE group performed deep squat, bench press, and hard pull training in sequence with 70-75% 1 repetition maximum. Body composition, cardio-vascular function indicators were measured before and after the interventions. After eight weeks, body fat percentage was reduced in both groups (AE: P < 0.0001, RE:P = 0.03). Hemodynamic indices (P < 0.05), endothelium-dependent diastolic function (AE:P = 0.01, RE:P = 0.024) and endothelial nitric oxide synthase (P < 0.0001) were increased. Both AE and RE exercise increased cardiac function (P < 0.05). The RE group (P = 0.002) had a significantly higher muscle mass. Brachial-ankle pulse wave conduction velocity (left: P = 0.006; right: P < 0.0001) was significantly lower in the AE group. Both AE and RE significantly reduced the body fat percentage, improved cardiac function, hemodynamic, and vascular endothelial function in obese young adults. AE has a stronger effect on reducing arterial stiffness, whereas resistance exercise has a stronger effect on building muscle, but does not change arterial stiffness.

Effect of Acute Resistance Exercise and Resistance Exercise Training on Central Pulsatile Hemodynamics and Large Artery Stiffness: Part I

Background

Engaging in habitual resistance exercise training (RET; also known as strength training) causes systemic health effects beyond those caused by aerobic/endurance exercise training alone. Despite the resoundingly favorable effect of habitual RET on measures of cardiovascular disease risk, controversy still exists regarding the vascular health effects of this exercise modality largely because some studies find increases in large artery stiffness and central pulsatile hemodynamics with RET. In this two-part series, we examine the effect of acute resistance exercise (RE) and RET on large artery stiffness and pulsatile hemodynamics. We perform a historical overview of seminal/classic studies and report on key findings that have shaped the field. We provide personal commentary on the studies and potential implications of findings related to the acute effects of RE on large artery stiffness and central pulsatile hemodynamics. For part one of this two-part series, we perform a detailed analysis of the hemodynamic signature produced during RE and discuss the sub-acute effects on short-term modulation of large artery stiffness and central pulsatile hemodynamics.

Summary

Acute RE elicits marked ("extreme") elevations in arterial pressure, mediated primarily by increases in vascular resistance and intrathoracic pressure (ITP). Vascular compression from muscular contraction contributes to increases in afterload via increased vascular resistance and pressure from wave reflections. However, as a result of the higher ITP associated with breath holds (Valsalva maneuver) during high relative efforts (>80%), the change in pressure across the aortic wall (transmural pressure) is less than the change in intra-arterial pressure.

Key Messages

The high arterial pressures during some heavy weight lifting exercises are associated with positive swings with ITP related to the Valsalva maneuver and elevations in vascular resistance. The pressure oscillations lead to marked stress within the vascular wall and likely contribute to elevations in large artery stiffness over the subsequent hour.

The influence of physical activity and sex on carotid artery longitudinal wall motion in younger healthy adults

Carotid artery longitudinal wall motion (CALM) is a novel preclinical marker for atherosclerosis that describes the axial anterograde and retrograde motion of the intima-media complex. While regular physical activity and sex are known to independently influence arterial stiffness, their roles on axial arterial wall behaviour are unknown. The purpose of this study is to examine whether physical activity and sex impact CALM. We hypothesized that CALM retrograde displacement and total amplitude would be greater in females and active individuals, as a function of arterial stiffness. Fifty-seven young healthy adults (30 females; aged 22 ± 3 years) were evaluated for CALM outcomes and arterial stiffness and grouped by physical activity based on active (V̇O2 = 44.2 ± 8.9 mL/kg/min) or sedentary (V̇O2 = 33.7 ± 6.7 mL/kg/min) lifestyles defined by the Canadian 24-Hour Movement Guidelines. Arterial stiffness and CALM were measured by carotid-femoral pulse wave velocity (cfPWV) and vascular ultrasound at the right common carotid artery with speckle tracking analysis, respectively. cfPWV was greater in males (p < 0.01) with no interaction between sex and physical activity (p = 0.90). CALM anterograde displacement was greater in males (p = 0.03) resulting in a forward shift in total CALM pattern, which became less prominent when controlling for mean arterial pressure (p = 0.06). All other CALM outcomes were not different between activity and sex. V̇O2max was not correlated to any CALM outcome (all p > 0.05). Apparent sex differences in vascular function extend to novel CALM outcomes but may be confounded by blood pressure. We recommend sex-balanced design and reporting in future studies due to possible anterograde-shifted CALM patterns in healthy males.