Effects of acute resistance exercise on arterial stiffness in young men

The Value of Serial Measurement of Arterial Stiffness in Cardiovascular Disease

Clinically assessing arterial stiffness is valuable because it aids in predicting future cardiovascular events. There are several methods for measuring arterial stiffness, including pulse wave velocity (PWV), augmentation index, and pulse pressure. Numerous studies have shown that these indicators of arterial stiffness possess prognostic value for various patient groups as well as the general population. In cross-sectional studies, arterial stiffness was also linked to organ damage indices. However, most studies related to arterial stiffness have relied on a single measurement. Taking multiple serial measurements of arterial stiffness offers several advantages. Through repeated assessments, one can confirm the variability of arterial stiffness and observe changes over time, which is beneficial for understanding its pathophysiology. Such repeated measurements are also invaluable in evaluating the efficacy of interventions aimed at improving arterial stiffness. However, caution is needed, as there is no standardized method for measuring arterial stiffness. For instance, with PWV, the values can be influenced by numerous external factors. Therefore, the external conditions during the measurement must be noted. It's essential to recognize the pros and cons of repeated arterial stiffness measurements and integrate them effectively into clinical practice.

Effects of resistance exercise alone or with caffeine on hemodynamics, autonomic modulation and arterial stiffness in resistance-trained women

AIM

Both an acute bout of resistance exercise (RE) and caffeine consumption can significantly alter hemodynamics, autonomic modulation, and arterial stiffness, which may correlate with adverse cardiovascular events. However, effects of an acute bout of RE and caffeine are unclear in resistance-trained women.

PURPOSE

The purpose of this study was to compare the effects of an acute bout of RE with repetitions to failure on squat and bench press, with or without caffeine, on performance, resting and recovery measures of hemodynamics, autonomic modulation, as well as arterial stiffness in resistance-trained women.

METHODS

Eleven women participated in a double-blind, placebo controlled cross-over design in which they consumed caffeine (4 mg/kg) or placebo at least 72 h apart. Sixty minutes following ingestion, participants performed two sets of 10 repetitions followed by a third set to failure on squat and bench press. Hemodynamics, autonomic modulation, and arterial stiffness were measured at rest, 60 min post-ingestion, and three minutes and 10 min following RE.

RESULTS

Data demonstrated caffeine has no additive effects on performance, hemodynamics, autonomic modulation, or arterial stiffness (p > 0.05) before or following an acute bout of RE in resistance-trained women compared to a placebo.

CONCLUSIONS

Resistance-trained women may not observe any alteration to RE performance on the squat and bench press in terms of repetitions to failure following caffeine ingestion. In addition, the data from the present study suggests that there may also not be any further negative effects on the cardiovasculature if caffeine is consumed prior to the RE bout.

Effect of Exercise on Arterial Stiffness in Healthy Young, Middle-Aged and Older Women: A Systematic Review

Arterial stiffness, an age-dependent phenomenon, is improved with exercise, which in turn may prevent cardiovascular diseases in women. However, there is a lack of consolidated information on the impact of exercise on arterial stiffness among healthy women. The aim of this review was to (i) analyse the effect of exercise on arterial stiffness in healthy young, middle-aged, and older women, and (ii) recommend types, intensity, and frequency for each age group. Database searches on PubMed, ScienceDirect, Web of Science, and Scopus were conducted using PRISMA guidelines until September 2022. The keywords were: exercise, women/female, and arterial stiffness. The inclusion criteria were: healthy women, supervised exercise, and arterial stiffness measures. Study quality and bias were assessed using the PEDro scale. Fifty-one papers were classified into young (n = 15), middle-aged (n = 14), and older (n = 22) women. Improvements in arterial stiffness were observed among: young women (Pulse Wave Velocity, PWV: 4.9-6.6 m/s), following an 8-week high-intensity aerobic (3 days/week) or hypoxic high-intensity interval training; middle-aged women (PWV: 5.1-7.9 m/s), aerobic exercise with moderate intensity or stretching exercise at "moderate to heavy" (Borg Scale), 20-30 s per site, 10 s of rest interval for 30 min; and for older women (PWV: 7.9-15.6 m/s), resistance training at light intensity, aerobic exercise at any intensity, or a combination of the two exercises. This review shows that arterial stiffness increases with age in healthy women and has an inverse relationship with exercise intensity. Therefore, when prescribing exercise to improve arterial stiffness, age and arterial stiffness measures should be accounted for.

Acute arterial stiffness responses to on-ball balance exercises in young and middle-aged adults: Role of posture and cumulative effects

Objective: To examine the acute arterial stiffness changes after maintaining one bout of balance on Swiss ball using different postures in young and middle-aged adults, and to evaluate the cumulative exposure effects on arterial stiffness after multiple exercise bouts in middle-aged adults. Methods: Using crossover design, we first enrolled 22 young adults (24.0 ± 1.1 years) and randomized them to non-exercise control (CON), on-ball balance exercise trial lasting 1 × 5 min in kneeling posture (K1) and sitting posture (S1). In a following crossover experiment, 19 middle-aged adults (53.0 ± 4.7 years) were randomized to non-exercise control (CON), on-ball balance exercise trial lasting 1 × 5 min in kneeling posture (K1) and in sitting posture (S1), and on-ball balance exercise trial lasting 2 × 5 min in kneeling posture (K2) and in sitting posture (S2). Cardio-ankle vascular index (CAVI), an indicator of systemic arterial stiffness, was measured at baseline (BL), immediately after (0 min), and every 10 min after exercise. CAVI changes from BL in the same trial (⊿CAVI) were used for analysis. Results: In K1 trial, ⊿CAVI decreased significantly at 0 min (p < 0.05) in both young and middle-aged adults; however in S1 trial, ⊿CAVI at 0 min increased significantly in young adults (p < 0.05), with ⊿CAVI tending to increase in middle-aged adults. Bonferroni post-test revealed that at 0 min, ⊿CAVI of K1 in both young and middle-aged adults, and ⊿CAVI of S1 in young adults differed significantly from that of CON (p < 0.05). In middle-aged adults, ⊿CAVI decreased significantly at 10 min compared to BL in K2 trial (p < 0.05), and increased at 0 min compared to BL in S2 trial (p < 0.05); however, difference compared to CON was not significant. Conclusion: Single on-ball balance bout in kneeling posture improved arterial stiffness transiently in both young and middle-aged adults; however, sitting posture elicited opposite changes, and this happened only in young adults. Multiple balance bouts resulted in no significant change in arterial stiffness in middle-aged adults.

Arterial Stiffness Response to Acute Combined Training with Different Volumes in Coronary Artery Disease and Heart Failure Patients

Resistance training has been shown to acutely increase arterial stiffness (AS), while endurance training appears to decrease AS. However, the findings are from studies in apparently healthy subjects and have limited applicability to patients at low and high cardiovascular risk, for whom combined exercise is recommended. We compared the time course of changes in local and regional indices of AS in response to high-volume combined endurance training (CET) and high-volume combined resistance training (CRT) in patients with coronary artery disease (CAD) and heart failure (HF). We studied 20 men with CAD and HF (10 each) aged 68.3 ± 9.6 years. AS was measured by pulse wave velocity (PWV), and brachial and central blood pressure (BP) were determined after 15 min of rest and 5 and 15 min after the exercise session. All patients completed two sessions on nonconsecutive days. A protocol by time interaction effect was observed for carotid (η² = 0.21, p = 0.02), aortic (η² = 0.60, p < 0.001), and femoral (η² = 0.46, p = 0.01) PWV after CET and CRT, suggesting that PWV decreased after CET and increased after CRT. Decreases in the brachial and central variables of BP across time points were observed in both protocols. CET decreased whereas CRT increased carotid, aortic, and femoral PWV at 15 min after exercise in patients with CAD and HF.

Arterial Stiffness following Endurance and Resistance Exercise Sessions in Older Patients with Coronary Artery Disease

Arterial stiffness (AS) is associated with coronary artery disease (CAD). Acute endurance training decreases AS, whereas acute resistance training increases it. However, these results are from studies in apparently healthy adults, and there is no information on the effects of such afterload AS in elderly patients with CAD. We aimed to investigate the effect of acute endurance or resistance training on the time course of changes in the indices of AS in elderly patients with CAD in order to understand how stiffness responds after training. We tested 18 trained men with CAD. AS was measured using central and peripheral pulse wave velocity (PWV) after 15 min of rest and after 5, 15, and 30 min of endurance and resistance training sessions. The endurance session consisted of high-intensity interval walking at 85-90% of maximum heart rate, and the resistance session consisted of 70% of the maximum of one repetition. An interaction effect was found for central and peripheral PWV (p ≤ 0.001; carotid, η² = 0.72; aortic, η² = 0.90; femoral, η² = 0.74), which was due to an increase in PWV after resistance and a decrease in central and peripheral PWV after endurance. This study demonstrates that training mode influences the time course of AS responses to acute exercise in these patients. Acute endurance training decreased AS, whereas resistance training significantly increased it.

Changes in Arterial Stiffness in Response to Various Types of Exercise Modalities: A Narrative Review on Physiological and Endothelial Senescence Perspectives

Arterial stiffness is a reliable independent predictor of cardiovascular events. Exercise training might enhance arterial compliance through improved metabolic health status. Different modes of exercise may have different effects on arterial stiffness. However, the interactions among different modes of exercise on endothelial senescence, the development of arterial vascular stiffness, and the associated molecular mechanisms are not completely understood. In this narrative review, we evaluate the current evidence focusing on the effects of various exercise modes on arterial stiffness and vascular health, and the known underlying physiological mechanisms are discussed as well. Here, we discuss the most recent evidence of aerobic exercise, high-intensity interval training (HIIT), and resistance exercise (RE) on arterial stiffness and endothelial senescence in physiological and cellular studies. Indeed, aerobic, HIIT, and progression RE-induced arterial compliance may reduce arterial stiffness by effectively promoting nitric oxide (NO) bioavailability and reducing endothelial senescence. However, the transient increase in inflammation and sympathetic activation may contribute to the temporary elevation in arterial stiffness following whole-body high-intensity acute resistance exercise.

Sex Differences in Measures of Wave Reflection and Aortic Arterial Stiffness in Response to Weight Machine Resistance Exercise

While it has been demonstrated that acute resistance exercise (RE) alters measures of wave reflection and aortic arterial stiffness in young, healthy individuals, limited research has evaluated sex differences. Accordingly, we recruited moderately active, resistance-trained men (Age: 22 ± 3yrs, n=12) and women (23 ± 3yrs, n=10) to perform two randomized conditions consisting of an acute bout of weight machine RE or a quiet control (CON). Measures of aortic wave reflection and aortic stiffness were taken at baseline and 15 minutes following the RE (Recovery). At baseline, women had significantly higher heart rate (p = 0.05) and lower brachial systolic blood pressure (p = 0.009) compared to men. There were no significant three-way interactions for any variable. Significant condition by time interactions were noted for heart rate (Baseline: 65 ± 10bpm, Recovery: 87 ± 13bpm, p = 0.001), brachial systolic blood pressure (Baseline: 116 ± 9mmHg, Recovery: 123 ± 10mmHg, p = 0.014), and the augmentation index (AIx) normalized at 75bpm (Baseline: 7.7 ± 12.8%, Recovery: 15.5 ± 9.5%, p = 0.002) such that Recovery was augmented compared to Baseline following RE but not CON. There was also a significant main effect of time for augmentation pressure (Baseline: 4.1 ± 4.0mmHg, Recovery: 4.0 ± 3.6mmHg, p = 0.04) such that it decreased from Baseline to Recovery following RE but not the CON. There were no significant effects of sex, condition, or time on aortic arterial stiffness. Men and women have similar responses in measures of aortic wave reflection and aortic arterial stiffness following acute RE using weight machines.

Effects of acute sympathetic activation on the central artery stiffness after strenuous endurance exercise

Purpose

Augmented central arterial stiffness (CAS) increases cardiovascular risk. CAS can be augmented by physical exercise and sympathetic activation (SYMP) induced by stressful stimuli. Interestingly, sympathetic vasoconstriction triggered by a sympathetic stimulant is augmented immediately after a strenuous half-marathon compared to at rest. This study assessed whether CAS also augments more post- than pre-half-marathon in response to SYMP. Such assessment takes on relevance considering the growing popularity of strenuous, long-distance endurance exercises.

Methods

13 healthy recreational runners (age 46.1 ± 6.5 years; $$V^{\prime}{\text{O}}_{2} \max$$ V ′ O 2 max 54.23 ± 9.31 mlO2/min/kg) provided the following measurements prior to and within 10 min following a strenuous half-marathon: beat-by-beat aortic pulse wave velocity (aPWV; index of CAS), mean blood pressure, and heart rate assessment. Measures were performed at rest and during a 2 min handgrip-mediated SYMP. The effects of the half-marathon and SYMP were assessed by two-way repeated-measures ANOVA.

Results

Measurements of the aPWV pre- and post-race were not significantly different (7.5 ± 0.8 vs 7.8 ± 0.8 m/s, p = 0.34; pre- vs post-race). 2 min of SYMP increased the baseline aPWV post-race (7.8 ± 0.8 vs 8.4 ± 0.8, p = 0.003; rest vs SYMP) but not pre-race (7.5 ± 0.8 vs 7.9 ± 0.9, p = 0.21).

Conclusion

The baseline aPWV assessed 7 to 8 min after a strenuous half-marathon is similar to that pre-race in healthy runners. This agrees with previous studies suggesting CAS being at or below resting values > 5 min following completion of aerobic exercises. The same sympathetic stressor augments CAS to a greater extent 8–10 min post-race than pre-race, suggesting a greater post-exercise stiffening of central artery segments triggered by the same task.

The Effect of a Single Bout of Resistance Exercise with Blood Flow Restriction on Arterial Stiffness in Older People with Slow Gait Speed: A Pilot Randomized Study

Purpose: Low-intensity resistance exercise with moderate blood-flow restriction (LIRE-BFR) is a new trending form of exercises worldwide. The purpose of this study was to compare the acute effect of a single bout of traditional resistance exercise (TRE) and LIRE-BFR on arterial stiffness in older people with slow gait speeds. Methods: This was a randomized, controlled clinical study. Seventeen older adults (3 men; 14 women; 82 ± 5 years old) completed a session of TRE (n = 7) or LIRE-BFR (n = 10). At baseline and after 60 min post-exercise, participants were subject to blood pressure measurement, heart rate measurements and a determination of arterial stiffness parameters. Results: There was no significant difference between the TRE and LIRE-BFR group at baseline. Pulse-wave velocity increased in both groups (p < 0.05) post-exercise with no between-group differences. Both exercise modalities did not produce any adverse events. The increase in systolic blood pressure, pulse pressure, augmentation pressure and pulse wave velocity (all p > 0.05) were similar after both TRE and LIRE-BFR. Conclusion: TRE and LIRE-BFR had similar responses regarding hemodynamic parameters and pulse-wave velocity in older people with slow gait speed. Long-term studies should assess the cardiovascular risk and safety of LIRE-BFR training in this population.

Arterial Stiffness Alterations in Simulated Microgravity and Reactive Sledge as a Countermeasure

INTRODUCTION

Experiments during spaceflight and simulated microgravity as head-down tilt bedrest, demonstrated the role of arterial stiffness among others, in microgravity induced cardiovascular pathologies and emphasized the need for a robust countermeasure.

AIM

The purpose of the present study was to evaluate the use of a new countermeasure, consisting of a high intensity Reactive Sledge (RSL) jumps training protocol, to counteract changes in arterial stiffness during long term head down tilt bedrest (LTBR).

METHODS

The participants enrolled in the study were 23 male, healthy volunteers, aged between 20 and 45 years, subjected to LTBR for 60 days and randomly assigned either to a control (11) or to a training sledge (12) group using RSL 3-4 times per week, as a countermeasure. Recorded values were systolic and diastolic blood pressure, heart rate and the user's arterial stiffness index.

RESULTS

Compared to baseline measurements, there was a deterioration in the values of arterial stiffness, systolic and diastolic blood pressure and heart rate, in both groups until day 35 of LTBR, interpreted as adaptation to the microgravity environment. From this day until the end of the experiment, arterial stiffness of the control group was constantly fluctuating, while constantly improving for the training group. During the recovery period, arterial stiffness values returned to the pre-experimental levels in both groups.

CONCLUSIONS

Overall, arterial stiffness increased the longer the time spent in LTBR and the countermeasure was partially effective in preventing the observed phenomenon. German Clinical Trials Register (DRKS), DRKS00012946, September 18, 2017, retrospectively registered.

Vascular Ageing and Aerobic Exercise

Impairment of vascular function, in particular endothelial dysfunction and large elastic artery stiffening, represents a major link between ageing and cardiovascular risk. Clinical and experimental studies identified numerous mechanisms responsible for age-related decline of endothelial function and arterial compliance. Since most of these mechanisms are related to oxidative stress or low-grade inflammation, strategies that suppress oxidative stress and inflammation could be effective for preventing age-related changes in arterial function. Indeed, aerobic physical activity, which has been shown to improve intracellular redox balance and mitochondrial health and reduce levels of systemic inflammatory markers, also improves endothelial function and arterial distensibility and reduces risk of cardiovascular diseases. The present paper provides a brief overview of processes underlying age-related changes in arterial function, as well as the mechanisms through which aerobic exercise might prevent or interrupt these processes, and thus attenuate vascular ageing.

Low-to-Moderate-Intensity Resistance Exercise Effectively Improves Arterial Stiffness in Adults: Evidence From Systematic Review, Meta-Analysis, and Meta-Regression Analysis

Background/Purpose: Resistance exercise (RE) is known to improve cardiovascular health, but the role of RE variables on arterial stiffness is inconclusive. In this systematic review and meta-analysis, we investigated the influence of RE and its intensities on arterial stiffness measured as pulse wave velocity (PWV) in young and middle-aged adults. Methods: Web of Science, PubMed/MEDLINE, Scopus, EMBASE, Cochrane Library, ScienceDirect, CINAHL, Wiley Online Library, and Google Scholar were searched for relevant studies. RE trials that reported PWV data, and compared with respective controls were included. The Cochrane Collaboration tool was used to assess the risk of bias. Results: Data were synthesized from a total of 20 studies, involving 981 participants from control (n = 462) and exercise (n = 519) trials. The test for overall effect (pooled outcome) showed RE intervention had no effect on arterial stiffness (SMD = -0.09; 95% CI: -0.32, 0.13; P = 0.42), but risk of heterogeneity (I 2) was 64%. Meta-regression results revealed a significant correlation (P = 0.042) between RE intensity and PWV changes. Consequently, the trials were subgrouped into high-intensity and low-to-moderate-intensity to identify the effective RE intensity. Subgroup analysis showed that low-to-moderate-intensity significantly decreased PWV (SMD = -0.34; 95% CI: -0.51, -0.17; P < 0.0001), while high-intensity had no effect (SMD = 0.24; 95% CI: -0.18, 0.67; P = 0.26). When trials separated into young and middle-aged, low-to-moderate-intensity notably decreased PWV in young (SMD = -0.41; 95% CI: -0.77, -0.04; P = 0.03) and middle-aged adults (SMD = -0.32; 95% CI: -0.51, -0.14; P = 0.0007), whereas high-intensity had no effect in both age groups. Conclusions: Our findings demonstrated that RE intensity is the key variable in improving arterial stiffness. Low-to-moderate-intensity can prescribe as an effective non-pharmacological strategy to treat cardiovascular complications in young and middle-aged adults.

Effect of an Acute Resistance Training Bout and Long-Term Resistance Training Program on Arterial Stiffness: A Systematic Review and Meta-Analysis

Resistance training (RT) and exercise is useful for preventing cardiovascular disease, systolic hypertension and stroke, which are associated with the stiffening of the larger central arterial system. The aim of this systematic review was to (a) understand the changes in arterial stiffness (AS) in various parts of the body measurement after acute RT bout and long-term RT, and (b) to determine the impact of exercise intensity on these changes in healthy individuals. A systematic computerized search was performed according to the PRISMA in PubMed, Scopus and Google Scholar with final selection of 23 studies. An acute RT bout led to a temporary increase in pulse wave velocity (PWV) regardless of the measurement method or intensity. A long-term RT at above an 80% repetition maximum (RM) have an ambiguous effect on PWV. A low-intensity RT or whole-body vibration training program decreased carotid-femoral PWV and brachial-ankle PWV (d = 1.02) to between 0.7 ± 1.4 ms-1 (p < 0.05) and 1.3 ± 1.07 ms-1 (p < 0.05) and improved other cardiac functions. A long-term RT of moderate (60-80% 1RM) or low intensity (<60% one-repetition maximum (1RM)) can decrease AS. Low and moderate intensity RT is beneficial to reduce high AS to prevent cardiovascular diseases.

The Acute Effect of Exercise on Arterial Stiffness in Healthy Subjects: A Meta-Analysis

Arterial stiffness has been shown to be a subclinical marker associated with cardiovascular disease. Meanwhile, long-term exercise has been demonstrated to reduce arterial stiffness, providing a decrease in cardiovascular risk. However, the acute effect of exercise on arterial stiffness is unclear. This systematic review and meta-analysis aimed to assess the acute effect of exercise interventions on arterial stiffness in healthy adults. We searched the Cochrane Central Register of Controlled Trials, MEDLINE (via Pubmed), Scopus, and Web of Science databases, from their inception to 30 June 2020. A meta-analysis was performed to evaluate the acute effect of exercise on arterial stiffness using random-effects models to calculate pooled effect size estimates and their corresponding 95% CI. Pulse wave velocity was measured as an arterial stiffness index. The 30 studies included in the meta-analysis showed that pulse wave velocity was not modified immediately after exercise (0 min post) (ES: 0.02; 95% CI: −0.22, 0.26), but subsequently decreased 30 min after exercise (ES: −0.27; 95% CI: −0.43, −0.12). Thereafter, pulse wave velocity increased to its initial value 24 h after exercise (ES: −0.07; 95% CI: −0.21, 0.07). Our results show that, although there is a significant reduction in pulse wave velocity 30 min after exercise, the levels of arterial stiffness return to their basal levels after 24 h. These findings could imply that, in order to achieve improvements in pulse wave velocity, exercise should be performed on a daily basis.

Effects of aerobic, resistance and concurrent exercise on pulse wave reflection and autonomic modulation in men with elevated blood pressure

The acute effects of exercise modes on pulse wave reflection (PWR) and their relationship with autonomic control remain undefined, particularly in individuals with elevated blood pressure (BP). We compared PWR and autonomic modulation after acute aerobic (AE), resistance (RE), and concurrent exercise (CE) in 15 men with stage-1 hypertension (mean ± SE: 34.7 ± 2.5 years, 28.4 ± 0.6 kg/m², 133 ± 1/82 ± 2 mmHg). Participants underwent AE, RE, and CE on different days in counterbalanced order. Applanation tonometry and heart rate variability assessments were performed before and 30-min postexercise. Aortic pressure decreased after AE (− 2.4 ± 0.7 mmHg; P = 0.01), RE (− 2.2 ± 0.6 mmHg; P = 0.03), and CE (− 3.1 ± 0.5 mmHg; P = 0.003). Augmentation index remained stable after RE, but lowered after AE (− 5.1 ± 1.7%; P = 0.03) and CE (− 7.6 ± 2.4% P = 0.002). Systolic BP reduction occurred after CE (− 5.3 ± 1.9 mmHg). RR-intervals and parasympathetic modulation lowered after all conditions (~ 30–40%; P < 0.05), while the sympathovagal balance increased after RE (1.2 ± 0.3–1.3 ± 0.3 n.u., P < 0.05). Changes in PWR correlated inversely with sympathetic and directly with vagal modulation in CE. In conclusion, AE, RE, and CE lowered central aortic pressure, but only AE and CE reduced PWR. Overall, those reductions related to decreased parasympathetic and increased sympathetic outflows. Autonomic fluctuations seemed to represent more a consequence than a cause of reduced PWR.

Effects of Resistance Training on Arterial Stiffness in Healthy People: A Systematic Review

The influence of aerobic training on cardiovascular disorders has already been demonstrated. However, the effect of resistance training is less well known. Arterial stiffness is an increasingly important measure in cardiovascular health. Therefore, this review attempted to study the results of resistance training-based interventions on arterial stiffness in healthy people, for both acute and chronic interventions. A literature search was conducted for randomized controlled trials on the acute and chronic effects of strength training. Studies published in PubMed and SportDiscus databases between 1999 and April 2019 were analyzed. In chronic strength training effects, the majority of groups showed large (d = -1.49 to -1.20) and moderate (d = -1.07) decreases, and small and trivial changes in arterial stiffness. In acute effects interventions, a very large decrease (d = -3.92) was observed, while large (d = 1.24-1.48) and very large (d = 3.88) increases were also found. A resistance training-based intervention of more than four weeks' duration with a frequency of two days per week seems not to compromise cardiovascular health, due to decreases in arterial stiffness. However, there is a general trend towards both increasing and maintaining arterial stiffness after isolated strength training sessions.

Influence of the order of aerobic and resistance exercise on hemodynamic responses and arterial stiffness in young normotensive individuals

AIMS

To investigate the effects of a combination of aerobic and resistance exercises and the inverse sequence on the hemodynamic parameters and indicators of arterial stiffness in healthy young adult subjects.

METHODS

Fifteen subjects were randomized in a crossover procedure according to two experimental conditions: combined aerobic exercise (30 min of treadmill running, 75-80% - peak VO₂) followed by resistance exercise (5 exercises, 3 sets - 10 RM) (AR) or vice versa (RA). Data of the hemodynamic parameters and arterial stiffness were obtained at baseline and after exercise (post-10, post-20, and post-30 min). Two-way ANOVA for repeated measurements was performed with the Newman-Keuls post-hoc. The significance level adopted was p < 0.05.

RESULTS

The results of the two-way ANOVA for repeated measures were not statistically significant for brachial and central systolic and diastolic blood pressure, respectively, or arterial stiffness indicators: reflected wave indicators and pulse wave velocity (P > 0.05). Statistically significant interactions were observed before and after the exercise sessions for heart rate and rate pressure product (P = < 0.001).

CONCLUSION

The performance order of aerobic exercise followed by resistance exercise (AR) and the reverse order (RA) present similar changes in blood pressure (BP) and arterial stiffness. However, resistance exercise before aerobic exercise promotes increases in heart rate and rate product pressure.

Low Dose Resistance Exercise: A Pilot Study Examining Effects on Blood Pressure and Augmentation Index Between Intensities

INTRODUCTION

The effects of resistance exercise on vascular function are unclear.

AIM

To investigate the acute haemodynamic (blood pressure and augmentation index) and rate of perceived exertion (RPE) response to two types of resistance exercises of equal workload-a set of unilateral 35% of one repetition maximum (1RM) quadriceps extension and a set of unilateral 70% 1RM quadriceps extension.

METHODS

Twenty two young healthy males completed both exercises on separate days. Heart rate, central and peripheral systolic and diastolic blood pressure (BP), augmentation pressure, augmentation index (AIx), augmentation index at a heart rate of 75 beats per minute (AIx75), and RPE were measured using applanation tonometry before exercise, immediately after exercise, 5 min after exercise and 15 min after exercise.

RESULTS

AIx75 was significantly lower 5 min after exercising at 35% of 1RM than 70% of 1RM. Systolic blood pressure was significantly lower at 5 min post exercise for both intensities. There was no significant difference in RPE between conditions or time points.

CONCLUSIONS

Results suggest that changes in blood pressure and augmentation index vary depending on the intensity of resistance exercise regardless of the volume of exercise carried out. Changes in AIx75 in response to resistance exercise may be independent of changes in BP.

The Acute Effects of High-Intensity Cycling Exercise on Arterial Stiffness in Adolescent Wrestlers

The aim of this study was to determine the acute effects of high‐intensity cycling exercise on the variables of carotid artery compliance, distensibility and beta stiffness index in elite adolescent wrestlers. The subjects were elite athletes competing in national, European and World Championships, who attended a training camp in the province of Kahramanmaras organized by the Turkish Centre for Olympic Preparation. The study sample comprised 31 male elite wrestlers with a mean age of 15.90 ± 0.87 years, body height of 165.97 ± 9.7 cm and body mass of 66.3 ± 18.45 kg. The arterial stiffness variables of the wrestlers were measured with high‐resolution Doppler ultrasonography before and 5 min after 30 s of high‐intensity cycling exercise (the Wingate Anaerobic Cycling test). The results showed a statistically significant correlation between mean power performance and carotid artery compliance at the 5th min after a single cycling sprint exercise (p < 0.05). No correlation was determined between peak power and the arterial stiffness variables (p > 0.05). The study results indicate that acute changes in arterial stiffness variables are associated with the performance level of high‐intensity cycling exercise in a group of elite adolescent wrestlers.

Free-weight versus weight machine resistance exercise on pulse wave reflection and aortic stiffness in resistance-trained individuals

The purpose of this study was to compare the vascular responses to acute free-weight (FW) resistance exercise (RE) versus weight machines (WM). Thirty-two resistance-trained individuals participated in this study. Both modalities involved performing acute RE and a control. Blood pressure and measures of pulse wave reflection were assessed using pulse wave analysis. Aortic stiffness was assessed using carotid-femoral pulse wave velocity (cf-PWV). A repeated measures analysis of variance was used to determine the effects of modality (FW and WM) and condition (acute RE and control) across time (rest and 10-20 min after exercise) on measures of pulse wave reflection and aortic stiffness. Significance was set a priori at p ≤ 0.05. There were no modality by condition by time interactions for any variable, such that the FW and WM modalities responded similarly across time after acute RE (p > 0.05). There were significant (p ≤ 0.05) increases in heart rate, aortic systolic blood pressure, aortic pulse pressure, augmentation index normalized at 75bpm, and decreases in subendocardial viability ratio (SEVR) after acute RE, compared to rest. There was also a significant (p ≤ 0.05) increase in cf-PWV after acute RE, compared to rest. In conclusion, this study demonstrates that acute free-weight and weight-machine RE are associated with transient increases in measures of pulse wave reflection and aortic stiffness, with reductions in myocardial perfusion. These data demonstrate that both modalities result in significant stress on the myocardium during recovery, while simultaneously increasing pressure on the aorta for at least 10-20 min.

Effects of a highly intensive clean and jerk exercise on blood pressure and arterial stiffness in experienced non-professional weight lifters

PURPOSE

Weight lifting training has gained much popularity in recent years and is frequently used in non-professional and professional settings. However, little is known about the acute effects of a highly intensive weight lifting exercise (clean and jerk) on the hemodynamic reaction.

METHODS

18 non-professional experienced weight lifters were recruited. Hemodynamic parameters were obtained and measured at baseline (T1), after warming up (T2), and after a highly intensive clean and jerk exercise (90-95% of personal best; T3). Further, 15 (T4), and 30 min (T5) post-exercise measurements were conducted. Evaluated parameters were heart rate (HR) (b/min), peripheral and central systolic and diastolic blood pressure (pSysBP, pDiaBP, cSysBP, cDiaBP) (mmHg), pulse wave velocity (PWV) (m/s), and double product (DP).

RESULTS

All hemodynamic values increased from T1 up to T3 with significantly higher values measured at T3 compared to T1 and T2. Values of measured parameters at T3 were as follows: HR: 94.4 ± 15.6 b/min, pSysBP: 147.1 ± 15.9 mmHg, pDiaBP: 87.4 ± 12.2 mmHg, cSysBP: 129.3 ± 13.8 mmHg, cDiaBP: 89.9 ± 12.8 mmHg, and: 5.8 ± 0.5 m/s, DP: 14053 ± 3669. Post-exercise (T4, T5), all values returned to baseline levels.

CONCLUSIONS

Results indicate that a highly intensive weight lifting exercise led to an acute increase of blood pressure and an acute stiffening of the arteries. Yet, increases were moderate and did not reach disproportionately high levels and returned to baseline levels within 15 min post-exercise. Hence, no negative acute effects of a maximum weight lifting exercise on the hemodynamic system are observed.

The Effect of 1 Week of a Multi-ingredient Dietary Preworkout Supplement on Resting and Postacute Resistance Exercise Vascular Function

Dietary preworkout supplements are popular among recreational exercisers and athletes. However, the effects of these supplements on the vasculature, both at rest and during exercise, are not well studied. Therefore, the purpose of this study was to determine the effect of 1 week of supplementation with a multi-ingredient dietary preworkout supplement on measures of vascular function at rest and immediately following acute resistance exercise in young, recreationally active adults. Twelve participants (9 males and 3 females; mean ± SD: age = 24.5 ± 3.4 years and body mass index = 24.3 ± 4.7 kg/m²) completed this double-blind, randomized, crossover design study. After familiarization, participants were randomized to either a taste-matched placebo or the preworkout supplement for 1 week preceding the testing visits. Participants underwent measures of vascular function, including brachial artery flow-mediated dilation, measures of central and peripheral blood pressure, and measures of arterial stiffness via pulse wave analysis and pulse wave velocity. All measures were taken at rest and immediately following an acute bilateral leg press exercise session. Resting and postacute exercise flow-mediated dilation, blood pressure, and arterial stiffness were similar between the placebo and the preworkout supplement visits. One week of multi-ingredient preworkout supplementation does not affect vascular function at rest or in response to an acute bout of resistance exercise in young, healthy, recreationally active individuals.

Influence of Exercise Mode on Post-exercise Arterial Stiffness and Pressure Wave Measures in Healthy Adult Males

Background: Exercise mode has been reported to be an important determinant of arterial stiffness and wave reflection changes following a brief bout of exercise with inconsistent results to date. This study examined the impact of exercise mode on arterial stiffness and pressure wave measures following acute aerobic exercise (AER), resistance exercise (RES), and a control (CON) condition with no exercise. Methods: In a randomized, cross-over, repeated measures design, 21 healthy adult males (26.7 ± 7.2 years) undertook three experimental intervention sessions: AER (30-min cycle ergometry at 70-75% maximum heart rate), RES (3 × 10 repetitions of six upper and lower body exercises at 80-90% of 10-repetition maximum) and CON (30-min seated rest). Measures of arterial stiffness and pressure waves, such as carotid-femoral pulse wave velocity (cf-PWV), augmentation index (AIx), AIx corrected for heart rate of 75 (AIx75), and forward wave (Pf), backward wave (Pb) and reflection magnitude, were assessed at Rest and at 10-min intervals for 60 min after the intervention sessions. Comparisons between interventions and over time were assessed via repeated measures ANOVA and post-hoc Tukey's tests. Results: No significant differences in cf-PWV were noted between the three interventions at rest or post-intervention. However, RES led to significantly greater post-intervention AIx, AIx75, Pf, and Pb compared to AER and CON with AIx75 also remaining significantly elevated throughout the post-intervention period. In contrast, AER resulted in a brief, significant elevation of AIx75 and no change in cf-PWV, Pf, Pb, and reflection magnitude. Conclusions: Exercise mode, specifically RES and AER, significantly influenced the time course of pressure wave reflection responses following a brief bout of exercise in healthy adult males. Distinct adjustments during exercise including changes in blood pressure and vasomotor tone may be key modulators of post-exercise arterial function. Identification of modal differences may assist in understanding the impact of exercise on cardiovascular function and the mechanisms by which exercise benefits vascular health.

Pulse wave reflection responses to bench press with and without practical blood flow restriction

Resistance exercise is recommended to increase muscular strength but may also increase pulse wave reflection. The effect of resistance exercise combined with practical blood flow restriction (pBFR) on pulse wave reflection is unknown. The purpose of this study was to evaluate the differences in pulse wave reflection characteristics between bench press with pBFR and traditional high-load bench press in resistance-trained men. Sixteen resistance-trained men participated in the study. Pulse wave reflection characteristics were assessed before and after low-load bench press with pBFR (LL-pBFR), traditional high-load bench press (HL), and a control (CON). A repeated-measures ANOVA was used to evaluate differences in pulse wave reflection characteristics among the conditions across time. There were significant (p ≤ 0.05) interactions for heart rate, augmentation index, augmentation index normalized at 75 bpm, augmentation pressure, time-tension index, and wasted left ventricular energy such that they were increased after LL-pBFR and HL compared with rest and CON, with no differences between LL-pBFR and HL. Aortic pulse pressure (p < 0.001) was elevated only after LL-pBFR compared with rest. In addition, there was a significant (p ≤ 0.05) interaction for aortic diastolic blood pressure (BP) such that it was decreased after LL-pBFR compared with rest and CON but not HL. The subendocardial viability ratio and diastolic pressure-time index were significantly different between LL-pBFR and HL compared with rest and CON. There were no significant interactions for brachial systolic or diastolic BP, aortic systolic BP, or time of the reflected wave. In conclusion, acute bench press resistance exercise significantly altered pulse wave reflection characteristics without differences between LL-pBFR and HL.

Effects of Exercise Training in Hypoxia Versus Normoxia on Vascular Health

BACKGROUND

Exercise training (ExT) prompts multiple beneficial adaptations associated with vascular health, such as increases in skeletal muscle capillarization and vascular dilator function and decreases in arterial stiffness. However, whether ExT performed in hypoxic conditions induces enhanced effects is unclear.

OBJECTIVE

We sought to systematically review the literature and determine whether hypoxic ExT leads to superior vascular adaptations compared with normoxic ExT.

METHODS

We searched MEDLINE, Scopus, and Web of Science from their inception until September 2015 for articles assessing vascular adaptations to ExT performed under hypoxic and normoxic conditions. We performed meta-analyses to determine the standardized mean difference (SMD) between the effects of ExT performed in hypoxia versus normoxia on vascular adaptations. We assessed heterogeneity among studies using I ² statistics and evaluated publication bias via the Begg and Mazumdar's rank correlation test and Egger's regression test.

RESULTS

After systematic review, we included 21 controlled studies, including a total of 331 individuals (mean age 19-57 years, 265 males). ExT programs primarily consisted of cycling endurance training performed in normobaric hypoxia or normoxia; duration ranged from 3 to 10 weeks. The exercise intensity was similar in relative terms in the groups trained in hypoxia and normoxia in the majority of studies (17 of 21). After data pooling, skeletal muscle capillarization (n = 182, SMD = 0.40, 95 % confidence interval [CI] 0.10-0.70; P = 0.01) and vascular dilator function (n = 71, SMD = 0.67, 95 % CI 0.17-1.18; P = 0.009) but not arterial stiffness (n = 112, SMD = -0.03, 95 % CI -0.69 to 0.63; P = 0.93), were enhanced with ExT performed in hypoxia versus normoxia. We only found heterogeneity among studies assessing arterial stiffness (I ² = 63 %, P = 0.02), and no publication bias was detected.

CONCLUSION

Based on current published studies, hypoxic ExT potentiates vascular adaptations related to skeletal muscle capillarization and dilator function. These findings may contribute to establishing effective exercise programs designed to enhance vascular health.

Small arteries stay stiff for a longer period following vibration exercises in combination with blood flow restriction

PURPOSE

The aim of this study was to assess the effect of isometric exercises performed during whole-body vibration (WBV) with and without blood flow restriction (BFR) on arterial elasticity and hemodynamic variables.

METHODS

Eight male subjects performed static upper body (UB) and lower body (LB) exercises on a vibration platform with and without BFR. During BFR sessions, BFR cuffs were placed on the arms or legs and inflated to a target pressure. Exercises consisted of eight 45-s sets for UB, and ten 1-min sets for LB. Arterial elasticity and hemodynamic variables were assessed before, at 10 min and 40 min postexercise. Repeated measures ANOVA was used to test the mean differences in related variables.

RESULTS

A significant condition (BFR versus no-BFR) main effect was detected for small arterial elasticity (P<0·05). For heart rate (HR), there were significant time (P<0·01), condition (P = 0·02) and body (P = 0·04) main effects during exercise and condition (P<0·04) and time (P<0·01) main effects following exercise. Significantly lower values in systemic vascular resistance were detected at 10 min post compared to 40 min post (P<0·02) and UB compared to LB (P = 0·02).

CONCLUSIONS

Results showed that small arteries stayed stiffer for a longer period of time after vibration exercises with BFR and BFR placed a greater demand on cardiovascular system. Findings also indicated that the type of exercises performed and/or the measurement location are very important and should be taken into account when examining arterial response.

Menstrual phase and the vascular response to acute resistance exercise

INTRODUCTION

Aerobic exercise has a favorable effect on systemic vascular function, reducing both central (large elastic artery) and peripheral (smaller muscular artery) stiffness. The effects of resistance exercise (RE) on arterial stiffness are more complex. Acute RE increases central artery stiffness while decreasing peripheral stiffness. To date, the majority of studies have been performed in predominantly male participants.

PURPOSE

To examine the effect of acute RE on central and peripheral arterial stiffnesses in women, a secondary purpose was to explore the influence of cyclic changes in estrogen status across the menstrual cycle on the arterial response to acute RE.

METHODS

18 healthy women [28 ± 7 years, body mass index (BMI) 22.6 ± 2.9 kg/m²] completed an acute RE bout during the early follicular and the early luteal phase of their menstrual cycle. Salivary 17β-Estradiol concentration was measured during each phase, using a passive drool technique. Pulse-wave velocity (PWV) was obtained from the carotid-femoral and carotid-radial pulse sites to measure central and peripheral stiffness, respectively, using applanation tonometry. PWV was measured at rest, immediately, 10, 20, and 30 min post-RE.

RESULTS

17β-Estradiol concentration was significantly lower in the early follicular vs. the early luteal phase of the menstrual cycle (1.78 ± 0.51 vs. 2.40 ± 0.26 pg/ml, p = 0.01). Central PWV significantly increased (p < 0.05) and peripheral PWV significantly decreased (p < 0.05) post-RE in both the early follicular and early luteal phases. No phase-by-time interaction was detected for either vascular segment (p > 0.05).

CONCLUSION

Women experience increases in central arterial stiffness and reductions in peripheral arterial stiffness following acute RE. Menstrual cycle phase may not influence changes in arterial stiffness in response to acute RE.

Acute Effects of Exercise Mode on Arterial Stiffness and Wave Reflection in Healthy Young Adults: A Systematic Review and Meta-Analysis

Background: This systematic review and meta-analysis quantified the effect of acute exercise mode on arterial stiffness and wave reflection measures including carotid-femoral pulse wave velocity (cf-PWV), augmentation index (AIx), and heart rate corrected AIx (AIx75). Methods: Using standardized terms, database searches from inception until 2017 identified 45 studies. Eligible studies included acute aerobic and/or resistance exercise in healthy adults, pre- and post-intervention measurements or change values, and described their study design. Data from included studies were analyzed and reported in accordance with the Cochrane Handbook for Systematic Reviews of Interventions and PRISMA guidelines. Meta-analytical data were reported via forest plots using absolute differences with 95% confidence intervals with the random effects model accounting for between-study heterogeneity. Reporting bias was assessed via funnel plots and, individual studies were evaluated for bias using the Cochrane Collaboration's tool for assessing risk of bias. A modified PEDro Scale was applied to appraise methodological concerns inherent to included studies. Results: Acute aerobic exercise failed to change cf-PWV (mean difference: 0.00 ms^-1 [95% confidence interval: -0.11, 0.11], p = 0.96), significantly reduced AIx (-4.54% [-7.05, -2.04], p = 0.0004) and significantly increased AIx75 (3.58% [0.56, 6.61], p = 0.02). Contrastingly, acute resistance exercise significantly increased cf-PWV (0.42 ms^-1 [0.17, 0.66], p = 0.0008), did not change AIx (1.63% [-3.83, 7.09], p = 0.56), and significantly increased AIx75 (15.02% [8.71, 21.33], p < 0.00001). Significant heterogeneity was evident within all comparisons except cf-PWV following resistance exercise, and several methodological concerns including low applicability of exercise protocols and lack of control intervention were identified. Conclusions: Distinct arterial stiffness and wave reflection responses were identified following acute exercise with overall increases in both cf-PWV and AIx75 following resistance exercise potentially arising fromcardiovascular and non-cardiovascular factors that likely differ from those following aerobic exercise. Future studies should address identified methodological limitations to enhance interpretation and applicability of arterial stiffness and wave reflection indices to exercise and health.

AORTIC POST-RESISTANCE EXERCISE HYPOTENSION IN PATIENTS WITH PERIPHERAL ARTERY DISEASE

ABSTRACT Introduction: A single session of resistance training decreases brachial blood pressure (BP) in patients with peripheral artery disease (PAD). However, it is not known whether similar responses occur in aortic BP, which is a better predictor of cardiovascular risk. Objective: This study aimed to analyze the effects of a single session of resistance training on aortic BP in PAD patients. Methods: This randomized, crossover, controlled trial involved 16 patients. All of them performed a session of resistance training (R - 3 x 10 reps in eight exercises, 5-7 on the OMNI Scale) and a control session (C - resting for 50 min). Before and after each session, aortic BP was assessed by applanation tonometry technique. Results: There was an increase in systolic (P<0.002) and mean (P<0.001) aortic BP in both sessions; however, higher increases were observed in C session (P<0.001). Additionally, diastolic aortic BP only increased after C session (P=0.004). The hypotensive effect of the exercise on systolic, diastolic, and mean aortic BP were -12±2, -6±2, and -7±2 mmHg, respectively. Conclusion: A single session of resistance training promoted a hypotensive effect on aortic BP of patients with PAD, indicating an acute reduction in cardiovascular risk in this population. Level of Evidence I; Therapeutic studies - Investigating the results of treatment.

Acute changes in arterial stiffness following exercise in people with metabolic syndrome

BACKGROUND

This study aims to examine the changes in arterial stiffness immediately following sub-maximal exercise in people with metabolic syndrome.

METHODS

Ninety-four adult participants (19-80 years) with metabolic syndrome gave written consent and were measured for arterial stiffness using a SphygmoCor (SCOR-PVx, Version 8.0, Atcor Medical Private Ltd, USA) immediately before and within 5-10min after an incremental shuttle walk test. The arterial stiffness measures used were pulse wave velocity (PWV), aortic pulse pressure (PP), augmentation pressure, augmentation index (AI), subendocardial viability ratio (SEVR) and ejection duration (ED).

RESULTS

There was a significant increase (p<0.05) in most of the arterial stiffness variables following exercise. Exercise capacity had a strong inverse correlation with arterial stiffness and age (p<0.01).

CONCLUSION

Age influences arterial stiffness. Exercise capacity is inversely related to arterial stiffness and age in people with metabolic syndrome. Exercise induced changes in arterial stiffness measured using pulse wave analysis is an important tool that provides further evidence in studying cardiovascular risk in metabolic syndrome.

Free-weight resistance exercise on pulse wave reflection and arterial stiffness between sexes in young, resistance-trained adults

We sought to determine the sex-specific effects of an acute bout of free-weight resistance exercise (RE) on pulse wave reflection (aortic blood pressures, augmentation index (AIx), AIx at 75 bpm (AIx@75), augmentation pressure (AP), time of the reflected wave (Tr), subendocardial viability ratio (SEVR)), and aortic arterial stiffness in resistance-trained individuals. Resistance-trained men (n = 14) and women (n = 12) volunteered to participate in the study. Measurements were taken in the supine position at rest, and 10 minutes after 3 sets of 10 repetitions at 75% 1-repetition maximum on the squat, bench press, and deadlift. A 2 × 2 × 2 ANOVA was used to analyse the effects of sex (men, women) across condition (RE, control) and time (rest, recovery). There were no differences between sexes across conditions and time. There was no effect of the RE on brachial or aortic blood pressures. There were significant condition × time interactions for AIx (rest: 12.1 ± 7.9%; recovery: 19.9 ± 10.5%, p = .003), AIx@75 (rest: 5.3 ± 7.9%; recovery: 24.5 ± 14.3%, p = .0001), AP (rest: 4.9 ± 2.8 mmHg; recovery: 8.3 ± 6.0 mmHg, p = .004), and aortic arterial stiffness (rest: 5.3 ± 0.6 ms; recovery: 5.9 ± 0.7 ms, p = .02) with significant increases during recovery from the acute RE. There was also a significant condition × time for time of the reflected wave (rest: 150 ± 7 ms; recovery: 147 ± 9 ms, p = .02) and SEVR (rest: 147 ± 17%; recovery: 83 ± 24%, p = .0001) such that they were reduced during recovery from the acute RE compared to the control. These data suggest that an acute bout of RE increases AIx, AIx@75, and aortic arterial stiffness similarly between men and women without significantly altering aortic blood pressures.

Arterial stiffness and stroke: de-stiffening strategy, a therapeutic target for stroke

Stroke is the second leading cause of mortality and morbidity worldwide. Early intervention is of great importance in reducing disease burden. Since the conventional risk factors cannot fully account for the pathogenesis of stroke, it is extremely important to detect useful biomarkers of the vascular disorder for appropriate intervention. Arterial stiffness, a newly recognised reliable feature of arterial structure and function, is demonstrated to be associated with stroke onset and serve as an independent predictor of stroke incidence and poststroke functional outcomes. In this review article, different measurements of arterial stiffness, especially pressure wave velocity, were discussed. We explained the association between arterial stiffness and stroke occurrence by discussing the secondary haemodynamic changes. We reviewed clinical data that support the prediction role of arterial stiffness on stroke. Despite the lack of long-term randomised double-blind controlled therapeutic trials, it is high potential to reduce stroke prevalence through a significant reduction of arterial stiffness (which is called de-stiffening therapy). Pharmacological interventions or lifestyle modification that can influence blood pressure, arterial function or structure in either the short or long term are promising de-stiffening therapies. Here, we summarised different de-stiffening strategies including antihypertension drugs, antihyperlipidaemic agents, chemicals that target arterial remodelling and exercise training. Large and well-designed clinical trials on de-stiffening strategy are needed to testify the prevention effect for stroke. Novel techniques such as modern microscopic imaging and reliable animal models would facilitate the mechanistic analyses in pathophysiology, pharmacology and therapeutics.

Response of Arterial Stiffness Four Weeks After Terminating Short-term Aerobic Exercise Training in a Sedentary Lifestyle

OBJECTIVES

The purpose of this study was to investigate the response of arterial stiffness in individuals with a sedentary lifestyle at 4 weeks after terminating a 2-week aerobic exercise session.

METHODS

Arterial stiffness was evaluated in 38 participants before starting and after completing a prescribed aerobic exercise program and also at 4 weeks after returning back to their sedentary lifestyle. Parameters regarding arterial compliance, distensibility, wall stress, and the elastic modulus were estimated from the information gained from sonography on the dimensions of carotid and femoral arteries and a sphygmomanometer on the pulse pressure.

RESULTS

Primary outcomes included whether short-term aerobic exercise reduced the heart rate, arterial pressure, and intima-media thickness and improved vascular biomechanics in physically inactive but otherwise healthy individuals. The benefits gained in arterial compliance and distensibility deteriorated with termination of exercise, but diastolic wall stress and the elastic modulus improved further.

CONCLUSIONS

In individuals with sedentary lifestyles, short-term aerobic exercise has strong four-week residual benefits on diastolic wall stress and the elastic modulus, but the effects appear to be negligible on arterial stiffness and distensibility.

Post-exercise effects on aortic wave reflection derived from wave separation analysis in young- to middle-aged pre-hypertensives and hypertensives

PURPOSE

Decreases in brachial blood pressure (BP) may occur for several hours following a bout of exercise. Although aortic backward waves predict cardiovascular damage independent of brachial BP, whether decreases in aortic backward waves also occur post-exercise in young-to-middle-aged hypertensives, the extent to which these changes exceed brachial BP changes, and the best method of identifying these changes is uncertain.

METHODS

We examined aortic function at baseline and 15-min post-exercise in 20 pre-hypertensive or hypertensive men and women (age 45 ± 7 years). Central aortic pressure, forward (Pf) and backward (Pb) wave pressures, the reflection index (RI) and augmentation pressure (AP) and index (AIx) were determined using applanation tonometry, and SphygmoCor software.

RESULTS

Decreases in central aortic (p < 0.001) but not brachial systolic BP and pulse pressure (PP) occurred post-exercise. In addition, decreases in post-exercise (baseline versus post-exercise) Pb (19 ± 4 vs 13 ± 3 mm Hg p < 0.0001), RI (72.9 ± 22.1 vs 47.6 ± 12.8 %, p < 0.0001), AIx (26.3 ± 10.8 vs 7.8 ± 11.6 %, p < 0.0001) and AP (9.9 ± 3.9 vs 2.8 ± 3.9 mm Hg, p < 0.0001), but not Pf, were noted. However, decreases in AIx were not correlated with decreases in Pb, and whilst decreases in aortic PP correlated with decreases in Pb (p < 0.0001), no correlations were noted with decreases in AP or AIx.

CONCLUSION

In young-to-middle-aged pre-hypertensive and hypertensive individuals, aortic backward waves decrease post-exercise; this change is not reflected in brachial BP measurements and is poorly indexed by measures of pressure augmentation.

Treadmill walking with load carriage increases aortic pressure wave reflection

INTRODUCTION AND OBJECTIVES

The study examined the effects of treadmill walking with load carriage on derived measures of central pressure and augmentation index in young healthy subjects.

METHODOLOGY

Fourteen male subjects (age 31.0 ± 1.0 years) volunteered in this study. Subjects walked 10 minutes on a treadmill at a speed of 5 km/h carrying no load during one session and a load of 10% of their body weight on both upper limbs in two water carboys with handle during the other session. Pulse wave analysis was performed at rest and immediately after exercise in the radial artery of the right upper limb by applanation tonometry.

RESULTS

The main result indicates that walking with load carriage sharply increased augmentation index at 75 bpm (-5.5 ± 2.2 to -1.4 ± 2.2% vs. -5.2 ± 2.8 to -5.5 ± 2.1%, p<0.05), and also induced twice as high increments in central pulse pressure (7.4 ± 1.5 vs. 3.1 ± 1.4 mmHg, p<0.05) and peripheral (20.5 ± 2.7 vs. 10.3 ± 2.5 mmHg, p<0.05) and central systolic pressure (14.7 ± 2.1 vs. 7.4 ± 2.0 mmHg, p<0.05).

CONCLUSIONS

Walking with additional load of 10% of their body weight (aerobic exercise accompanied by upper limb isometric contraction) increases derived measures of central pressure and augmentation index, an index of wave reflection and arterial stiffness.

Effect of acute resistance exercise on carotid artery stiffness and cerebral blood flow pulsatility

Arterial stiffness is associated with cerebral flow pulsatility. Arterial stiffness increases following acute resistance exercise (RE). Whether this acute RE-induced vascular stiffening affects cerebral pulsatility remains unknown. Purpose: To investigate the effects of acute RE on common carotid artery (CCA) stiffness and cerebral blood flow velocity (CBFv) pulsatility. Methods: Eighteen healthy men (22 ± 1 yr; 23.7 ± 0.5 kg·m⁻²) underwent acute RE (5 sets, 5-RM bench press, 5 sets 10-RM bicep curls with 90 s rest intervals) or a time control condition (seated rest) in a randomized order. CCA stiffness (β-stiffness, Elastic Modulus (Ep)) and hemodynamics (pulsatility index, forward wave intensity, and reflected wave intensity) were assessed using a combination of Doppler ultrasound, wave intensity analysis and applanation tonometry at baseline and 3 times post-RE. CBFv pulsatility index was measured with transcranial Doppler at the middle cerebral artery (MCA). Results: CCA β-stiffness, Ep and CCA pulse pressure significantly increased post-RE and remained elevated throughout post-testing (p < 0.05). No changes in MCA or CCA pulsatility index were observed (p > 0.05). There were significant increases in forward wave intensity post-RE (p < 0.05) but not reflected wave intensity (p > 0.05). Conclusion: Although acute RE increases CCA stiffness and pressure pulsatility, it does not affect CCA or MCA flow pulsatility. Increases in pressure pulsatility may be due to increased forward wave intensity and not pressure from wave reflections.

Intermittent, moderate-intensity aerobic exercise for only eight weeks reduces arterial stiffness: evaluation by measurement of stiffness parameter and pressure-strain elastic modulus by use of ultrasonic echo tracking

Background and purpose

Aerobic exercise has been reported to be associated with reduced arterial stiffness. However, the intensity, duration, and frequency of aerobic exercise required to improve arterial stiffness have not been established. In addition, most reports base their conclusions on changes in pulse wave velocity, which is an indirect index of arterial stiffness. We studied the effects of short-term, intermittent, moderate-intensity exercise training on arterial stiffness based on measurements of the stiffness parameter (β) and pressure–strain elastic modulus (E_p), which are direct indices of regional arterial stiffness.

Methods

A total of 25 young healthy volunteers (18 men) were recruited. By use of ultrasonic diagnostic equipment we measured β and E_p of the carotid artery before and after 8 weeks of exercise training.

Results

After exercise training, systolic pressure (P_s), diastolic pressure (P_d), pulse pressure, systolic arterial diameter (D_s), and diastolic arterial diameter (D_d) did not change significantly. However, the pulsatile change in diameter ((D_s − D_d)/D_d) increased significantly, and β and E_p decreased significantly.

Conclusions

For healthy young subjects, β and E_p were reduced by intermittent, moderate-intensity exercise training for only 8 weeks.