Effect of whole body resistance training on arterial compliance in young men

Effect of an 11-Week Resistance Training Program on Arterial Stiffness in Young Women

ABSTRACT

Morgan, B, Mirza, AM, Gimblet, CJ, Ortlip, AT, Ancalmo, J, Kalita, D, Pellinger, TK, Walter, JM, and Werner, TJ. Effect of an 11-week resistance training program on arterial stiffness in young women. J Strength Cond Res 37(2): 315-321, 2023-The current investigation was conducted to determine the effect of 2 resistance training models on indices of arterial stiffness in young, healthy women. Twenty-four women, untrained college students, aged 18-22 years were randomized into 1 of 3 groups: control (CON) group ( n = 8), high-intensity (HI) resistance exercise group ( n = 8), and high-volume (HV) resistance exercise group ( n = 8). Subjects randomized to resistance training groups were required to perform strength training exercises 3-5 days a week for 11 weeks. The exercise regimen consisted of 2-3 sets of 3-8 repetitions (80-90% of 1 repetition maximum [1RM]) for the HI group and 3-4 sets of 10-15 repetitions (50-70% of 1RM) for the HV group. All subjects were instructed to continue their normal diet and avoid cardiovascular exercise during the study. After the intervention, there was a significant increase in carotid femoral pulse wave velocity (PWV) (6.39 ± 0.73 to 8.40 ± 2.31 m·s -1 ; p < 0.05) and carotid radial PWV (9.77 ± 1.74 to 12.58 ± 2.09 m·s -1 ; p < 0.05) in the CON group alone. Both the HI and HV groups increased their maximum squat (36.6 ± 7.9 vs. 41.3 ± 31.8 percent change; p < 0.05), bench press (34.4 ± 12.6 vs. 23.4 ± 11.1 percent change; p < 0.05), and seated row (22.0 ± 12.6 vs. 21.9 ± 12.5 percent change; p < 0.05), respectively. Our findings support the use of resistance training exercise without undue impact on vascular compliance in otherwise healthy women.

High-Intensity Interval Training Combined with Different Types of Exercises on Cardiac Autonomic Function. An Analytical Cross-Sectional Study in CrossFit® Athletes

It is well established that endurance exercise has positive effects on cardiac autonomic function (CAF). However, there is still a dearth of information about the effects of regular high-intensity interval training combined with different types of exercises (HIITCE) on CAF.

OBJECTIVE

The aim of this study is to compare CAF at rest, its reactivity, and reactivation following maximal exercise testing in HIITCE and endurance athletes.

METHODS

An observational study was conducted with 34 male athletes of HIITCE (i.e., CrossFit^®) [HG: n = 18; 30.6 ± 4.8 years] and endurance athletes (i.e., triathlon) [TG.: n = 16; 32.8 ± 3.6 years]. We analyzed 5 min of frequency-domain indices (TP, LF, HF, LFn, HFn, and LF/HF ratio) of heart rate variability (HRV) in both supine and orthostatic positions and its reactivity after the active orthostatic test. Post-exercise heart rate recovery (HRR) was assessed at 60, 180, and 300 s. Statistical analysis employed a non-parametric test with a p-value set at 5%.

RESULTS

The HG showed reduced HFn and increased LFn modulations at rest (supine). Overall cardiac autonomic modulation (TP) at supine and all indices of HRV at the orthostatic position were similar between groups. Following the orthostatic test, the HG showed low reactivity for all HRV indices compared to TG. After the exercise, HRR does not show a difference between groups at 60 s. However, at 180 and 300 s, an impairment of HRR was observed in HG than in TG.

CONCLUSION

At rest (supine), the HG showed reduced parasympathetic and increased sympathetic modulation, low reactivity after postural change, and impaired HRR compared to TG.

Effects of aerobic, resistance, and combined training on endothelial function and arterial stiffness in older adults: study protocol for a systematic review and meta-analysis

INTRODUCTION

Aging is an independent risk factor for cardiovascular events. It promotes vascular dysfunction which is associated with risk factors for cardiovascular diseases (CVDs). Exercise can modulate vascular function parameters, but little is known about the effects of different modalities of training (aerobic, resistance, and combined) on endothelial function and arterial stiffness in older adults.

METHODS

This systematic review study will include randomized controlled trials (RCTs) selected from the electronic databases MEDLINE (PubMed), Cochrane, LILACS, EMBASE, and Web of Science. We will follow the PRISMA guidelines and PICOS framework. Studies involving both male and female older adults (≥60 years old) with or without comorbidities undergoing aerobic, resistance, and/or combined training compared to a control group (no exercise) will be eligible. We will use the Cochrane Risk of Bias 2 (RoB 2) tool to evaluate the quality of individual studies and GRADE to assess the strength of evidence. Statistical analyses will be conducted with RStudio for Windows (v1.3.959) using R package meta.

DISCUSSION

A systematic review and meta-analysis involving data from studies of older adults would deepen our understanding of vascular adaptations to exercise training in this population. It could provide new insights into how health providers can improve patient management and prevention of cardiovascular events in older adults.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO 42021275451.

Efeito de um Programa de Exercício Físico na Pressão Arterial Aguda e Crônica em Sobreviventes de Câncer de Mama

Introdução: Poucos estudos exploraram o desfecho de componentes hemodinâmicos em sobreviventes de câncer em um programa de exercícios físicos. Objetivo: Verificar alterações agudas e crônicas na pressão arterial sistólica (PAS) e diastólica (PAD) durante um programa de exercícios em sobreviventes de câncer de mama. Método: Um hospital de referência, 24 mulheres sobreviventes participaram de um programa de exercícios físicos. A PA foi monitorada com monitor digital de pulso, antes e após a realização das sessões. Para comparação pré e pós-exercício em cada sessão, foi empregado o teste t para amostras pareadas. Para analises dos efeitos crônicos, utilizou-se a analise de variância (Anova), com medidas repetidas para identificar possíveis diferenças nas variáveis PAS e PAD pré-exercício ao longo das 15 sessões de treinamento. Considerou-se o nível de significância de 5%. Resultados: Observou-se que, com exceção da quarta e sexta sessões, os níveis de PAS diminuíram em todas as sessões após o exercício (p≤0,05). Para a PAD, somente houve diminuição significativa após o exercício nas três primeiras sessões. Nos efeitos crônicos, ocorreu redução media nos valores de PAS em repouso ao longo das sessões, com efeito hipotensor acima de 70% a partir da sétima sessão (p≤0,05). Na PAD, diferenças nos valores em repouso se acentuaram a partir da decima sessão; ao comparar com os valores de PAD em repouso, verificou-se efeito hipotensor acima de 94%. Conclusão: Sobreviventes que aderiram ao programa de exercício físico apresentaram redução aguda e crônica da PAS e da PAD.

The Effect of Whole-Body Traditional and Functional Resistance Training on CAVI and Its Association With Muscular Fitness in Untrained Young Men

Background: Resistance training-induced changes in the muscle function is essential for the health promotion of the young and older, but the discrepancies of the effect of resistance training on arterial stiffness leads to the divergence regarding to the effect of resistance training on cardiovascular health. What confuses our understanding in this field may be the following factors: external load (higher intensity vs. lighter intensity), participants’ cardiovascular health, and arterial stiffness assessment measurement. The purpose of the present study was to investigate the effects of the whole-body traditional high-intensity vs. functional low-intensity resistance training protocol on systemic arterial stiffness, and their association with muscular fitness components in untrained young men.

Methods: In this randomized controlled trial, twenty-nine untrained young men (mean age about 22.5 years old) were randomized into a 6-weeks (three sessions per week) supervised whole-body traditional high-intensity resistance group (TRT, n = 15) consisting of 4–5 sets of 12 repetitions (70%1RM, lower-repetitions) or a whole-body functional low-intensity resistance group (FRT, n = 14) with 4–5 sets of 20 repetitions (40%1RM, higher-repetitions) to volitional failure. The systemic arterial stiffness (cardio-ankle vascular index, CAVI) and muscular fitness components were assessed before and after the 6-weeks training program.

Results: There was a significant decrease (pre-post) for CAVI only in FRT group (p < 0.05), but no significant difference was observed between two groups. In addition, the TRT and FRT groups showed equally significantly increased in maximal strength, muscular endurance and power (within group: both p < 0.01); however, the independent t test exhibited that the difference between two groups in terms of change in maximal strength, muscular endurance and power were no significant (p > 0.05). Furthermore, the reduction in CAVI was negatively correlated with the increase in 1RM of bench press for all participants (r = −0.490, p < 0.01).

Conclusion:Using present criterion-standard assessments measurements demonstrates that CAVI was significantly reduced after 6-weeks functional resistance training with beneficial effect on muscular fitness. Negative and significant association between CAVI and 1RM bench press indicated the cardiovascular health may be involved in the regulation of resistance training.

Effects of 6-Week Traditional and Functional Resistance Training on Arterial Stiffness and Muscular Strength in Healthy Young Men

Background

The present study investigated the effects of traditional resistance training (TRT) and functional resistance training (FRT) on arterial stiffness and muscular strength in healthy young men.

Methods

This randomized controlled trial included 29 untrained healthy young men aged 18–29 years who were randomly divided into two groups, namely, TRT group (n = 15) and FRT group (n = 14). All participants underwent numerous tests, such as those for body composition, cardio-ankle vascular index, blood pressure, heart rate, and maximal strength before and after the 6-week training program. The exercise training comprised whole-body strength training exercises 3 days a week for 6 weeks. The total training volume and number of sets (4–5 sets) were kept constantly similar in each group. The TRT group completed 4–5 sets of 8–12 repetitions [70% of 1 repetition maximum (1RM)], whereas the FRT group completed 4–5 sets of 15–22 repetitions (40% 1RM).

Results

The TRT and FRT groups exhibited equally significantly increased maximal strength (within group: both p < 0.01). Furthermore, the independent t-test showed that the differences between the two groups in terms of changes in maximal strength were no significant (between group: both p > 0.05). Additionally, significant main effects of time (pre vs. post) were observed for the left and right cardio-ankle vascular indices (p < 0.05); however, no significant difference were observed between the groups. For body compositions outcome measures, no significant differences between groups were observed.

Conclusion

Six weeks of FRT and TRT exhibit no difference in terms of effects on arterial stiffness and muscular strength.

Associations between duration and volume of muscle-strengthening exercise and clinically assessed hypertension among 10 519 UK adults: a cross-sectional study

BACKGROUND

Clinical evidence shows that muscle-strengthening exercise (MSE) is important for the treatment and management of hypertension. However, the links between MSE and hypertension in epidemiological research are currently poorly understood. This study examines the association between MSE duration and volume with clinically assessed hypertension.

METHODS

Cross-sectional data (n = 10 519, adults ≥16 years) were pooled from the Health Survey for England (2012, 2016). Self-reported MSE mode (own bodyweight; gym-based), duration, and volume were tested for associations with sphygmomanometer measured hypertension (SBP ≥ 130 mmHg or DBP ≥ 80 mmHg). Poisson regressions with robust error variance were used to calculate the prevalence ratios of hypertension (outcome variable) across MSE (exposure variables: duration (minutes [0 (reference); 10-20; 21-59; ≥60/session]); and volume [0 (reference); low <mean; high ≥mean/week]) for each mode and the modes combined.

RESULTS

Most adults (81.1%) did no MSE. However, in those who did (n = 1984), undertaking any MSE, regardless of mode, duration, or volume, was associated with a reduced likelihood of hypertension (adjusted prevalence ratios 0.61-0.90). When compared with the reference groups (no MSE), some modes had more favourable associations (e.g. ≥60 min/session of own bodyweight MSE; ≥mean min/week of gym-based MSE).

CONCLUSION

Irrespective of duration or volume, MSE was associated with a lower prevalence of clinically assessed hypertension. Public-health campaigns and other interventions that successfully promote small-to-moderate increases in MSE participation may reduce the prevalence of hypertension.

Body height determines carotid stiffness following resistance exercise in young Japanese men

Height is inversely associated with an increase in arterial stiffness after habitual resistance exercise (RE). Considering that RE is performed during exercise prescriptions, the association between height and the acute effects of RE on arterial stiffness should be clarified. We investigated the effects of height on arterial stiffness following transient RE. Thirty-nine young Japanese men were studied under parallel experimental conditions (sham control [seated rest] and RE [5 sets of 10 repetitions at 75% of one-repetition maximum]), which were randomly ordered on two separate days. The subjects were divided into tertiles of height (each group, n = 13). The β-stiffness index (index of arterial stiffness), assessed by carotid pulse pressure and distension, was measured in all subjects. A significant interaction between time, height, and RE was found for the β-stiffness index (P = 0.01). RE significantly increased the β-stiffness index in the lower height group (P < 0.001), but not in the middle and higher height groups. Height was negatively associated with an increase in β-stiffness index following RE, even after controlling the confounders, including exercise volume and changes in heart rate and carotid pulse pressure (P = 0.003). The mediation analysis demonstrated a mediating effect of carotid distension on the relationship between height and changes in the β-stiffness index. These results suggest that short height individuals have increased arterial stiffness following RE due to decreased mechanical distension, rather than through the widening of pulsatile pressure.

Effects of a 12-Week Resistance Training Program on Arterial Stiffness: A Randomized Controlled Trial

ABSTRACT

Werner, TJ, Pellinger, TK, Rosette, VD, and Ortlip, AT. Effects of a 12-week resistance training program on arterial stiffness: a randomized controlled trial. J Strength Cond Res 35(12): 3281-3287, 2021-Arterial stiffness is an indicator of disease and is an independent predictor of cardiovascular events. Some reports indicate that resistance training increases indices of arterial stiffness, whereas others report no association. This study sought to determine the association between 2 common resistance training models and indices of arterial stiffness. We recruited 30 male, untrained subjects (18-30 years) and randomized them into 1 of 3 groups: control (CON, n = 10), high-intensity resistance exercise (HI, n = 10), and high-volume resistance exercise (HV, n = 10). Subjects randomized to the resistance training groups were required to perform whole-body strength training exercises 3-5 days a week for 12 weeks. The exercise regimen consisted of 2-3 sets of 3-8 repetitions (80-90% of 1 repetition maximum [1RM]) for the HI group and 3-4 sets of 10-15 repetitions (50-70% of 1RM) for the HV group. Anthropometry, carotid artery diameters, peripheral and central blood pressure, and maximal dynamic strength were measured before and after the 12-week study period. Subjects were instructed to maintain their normal diet and avoid aerobic exercise during the study. After the intervention, both the HI and HV groups increased their maximal strength on the back squat, bench press, and seated row (all p < 0.05). However, there were no changes in arterial stiffness indices between the groups. Using a randomized controlled trial with validated measurements of arterial stiffness, chronic resistance training does not appear to influence central arterial stiffness, regardless of training volume and load.

Stature is negatively associated with increased arterial stiffness after high-intensity bicep curls training in young Japanese men

Reports have indicated that high-intensity resistance training (RT) increases or does not change arterial stiffness. Meanwhile, higher stature has been suggested to have a protective effect on cardiovascular disease and arterial stiffness. Stature could explain the disagreement in the reported effects of RT on arterial stiffness. This study was aimed at investigating whether stature is related to RT-induced change in arterial stiffness. Thirty-six young Japanese men were assigned to the control (n = 15) and training groups (n = 21). RT programme consisted of supervised bicep curls 3 days per week for 4 weeks (5 sets of 10 repetitions at 75% of 1-repetition maximum). Arterial compliance (AC) and β-stiffness index (via combination of ultrasound and carotid pressure waveforms) were measured in all participants. To verify the effect of stature on RT-induced change in arterial stiffness, the training group was divided into tertiles of stature: lower, middle, and higher stature groups (each group, n = 7). RT significantly decreased AC and increased β-stiffness index in only the lower stature group (both, P < 0.05). Moreover, stature was positively associated with decreased AC and negatively associated with increased β-stiffness index, even after adjusting for confounders including changes in relative strength, pulse pressure, and arterial distension (P < 0.05). The present results suggest that short stature contributes to the increase in arterial stiffness induced by RT in young Japanese men. The present findings suggest that stature should be taken into consideration when designing/engaging in RT programme, due to potential implications for cardiovascular health.Highlights Participants were divided into 3 groups according to tertiles of statures, and arterial stiffness of lower stature group (range of stature: 161.0-169.8 cm) increased after resistance training in young Japanese men, but not middle and higher stature group.Stature was negatively associated with the changed arterial stiffness by resistance training.This study suggests that short stature contributes to the elevation in arterial stiffness elicited by resistance training.

Brachial and central blood pressure and arterial stiffness in adult elite athletes

Purpose

Measures of arterial stiffness (AS) and central blood pressure (BP) are indicators for cardiovascular health and possess a high prognostic value in the prediction of cardiovascular events. The effects of physical training are widely unexplored in the context of competitive, high-performance sports. Therefore, we aimed to present possible reference values of brachial and central BP and of AS of adult elite athletes compared to a control group.

Methods

A total of 189 subjects participated in this cross-sectional study. Of these were 139 adult elite athletes (70 male, 69 female) performing on top-national and international level, and 50 control subjects (26 male, 24 female). Resting brachial and central BP and aortic pulse wave velocity (PWV) were measured and were compared in terms of sex, sport category, and age of the athletes.

Results

Results show no difference between athletes and controls in any parameter. Women exhibit lower brachial and central BP and AS values compared to men. PWV is positively correlated with age. Evaluation of the parameters according to the different sport categories showed that endurance athletes exhibit lower BP and PWV compared to other athletes.

Conclusions

This study presents brachial and central BP and PWV values of athletes, suggesting that high-performance sport does not negatively impact AS. The proposed reference values might support a more detailed evaluation of elite athlete’s cardiovascular and hemodynamic system and a better assignment to possible risk groups.

Is Stiffness Parameter β Useful for the Evaluation of Atherosclerosis?~ Its Clinical Implications, Limitations, and Future Perspectives ~

Atherosclerosis comprises two components, atherosis and sclerosis, characterized by morphological wall thickening and functional stiffening, respectively, of the arterial wall. In recent years, much interest has been directed to the role of functional changes in large arteries, i.e., increased stiffness or decreased elasticity, on the development of cardiovascular diseases. In fact, the clinical evaluation of arterial stiffness is increasingly performed in patients with cardiovascular risk factors. Local arterial stiffness is measured using an ultrasound technique implemented with an echo-tracking system at the common carotid and femoral arteries. Several indices of local arterial stiffness are obtained by ultrasound, among which stiffness parameter β is unique because it is the least affected by blood pressure at the time of measurement. Evidence from cross-sectional studies indicates that increased stiffness parameter β is associated with a number of cardiovascular risk factors, such as older age, smoking, insufficient physical activity, hypertension, obesity, metabolic syndrome, insulin resistance, type 2 diabetes, chronic kidney disease, and comorbid cardiovascular disease. Results from several prospective observational studies also suggest that carotid stiffness parameter β is a useful surrogate marker of cardiovascular events and/or mortality, although the results differ depending on the characteristics of the study subjects. Furthermore, several interventional studies have shown that carotid stiffness parameter β improved after lifestyle modification or drug treatment. In this review, we summarize the current evidence of stiffness parameter β of the carotid artery and discuss its clinical implications as a marker of vascular health or as a predictor of cardiovascular outcomes.

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.

The importance of physical function as a clinical outcome: Assessment and enhancement

The burgeoning population of older adults is intrinsically prone to cardiovascular disease (CVD) in a context of multimorbidity and geriatric syndromes. Risks include high susceptibility to functional decline, with many older adults tipping towards patterns of sedentary behavior and to downstream effects of frailty, falls, disability, poor quality of life, as well as increased morbidity and mortality even if the incident CVD was treated perfectly. While physical activity has been shown to moderate these patterns both as primary or secondary preventive medical care, the majority of older adults fail to meet physical activity recommendations. Clinicians of all specialities, including CVD medicine, can benefit from greater proficiency in functional assessments for their older adults, as well as from insights how to initiate effective functional enhancing approaches even in older adults who may be frail, deconditioned, and medically complex. Pertinent functional assessments include traditional cardiovascular metrics of cardiorespiratory fitness, as well as strength and balance. This review summarizes the components of a wide-ranging functional assessment that can be used to enhance care for older adults with CVD, as well as interventions to improve physical function.

Thigh muscle size and vascular function after blood flow-restricted elastic band training in older women

We examined the effect of elastic band training with blood flow restriction (BFR) on thigh muscle size and vascular function in older women. Older women were divided into three groups: low-intensity elastic band BFR training (BFR-Tr, n = 10), middleto high-intensity elastic band training (MH-Tr, n = 10), and no training (Ctrl, n = 10) groups. BFR-Tr and MH-Tr groups performed squat and knee extension exercises using elastic band, 2 days/week for 12 weeks. During BFR-Tr exercise session, subjects wore pressure cuffs around the most proximal region of both thighs. The following measurements were taken before (pre) and 3-5 days after (post) the final training session: MRI-measured muscle cross-sectional area (CSA) at mid-thigh, maximum voluntary isometric contraction (MVIC) of knee extension, central systolic blood pressure (c-SBP), central-augmentation index (c-AIx), cardio-ankle vascular index testing (CAVI), ankle-brachial pressure index (ABI). Quadriceps muscle CSA (6.9%) and knee extension MVIC (13.7%) were increased (p < 0.05) in the BFR-Tr group, but not in the MH-Tr and the Ctrl groups. Regarding c-SBP, c-AIx, CAVI and ABI, there were no changes between pre- and post- results among the three groups. Elastic band BFR training increases thigh muscle CSA as well as maximal muscle strength, but does not decrease vascular function in older women.

Physical Activity for the Prevention of Cardiovascular Diseases

Over the last decade, the quantity and quality of scientific literature examining the relationship between physical activity (PA) and cardiovascular diseases (CVD) have significantly increased. Data from the literature now unequivocally show that physical inactivity is one of the major risk factors for CVD. It is believed that obesity, the prevalence of which has tripled over the last three decades, and physical inactivity among children are the main factors that will increase the prevalence of CVD in this century. The cardiovascular benefits of exercise are multifactorial and include important systemic effects on skeletal muscle, the peripheral vasculature, metabolism, and neurohumoral systems, as well as beneficial alterations within the myocardium itself. Thus, exercise does much more than change traditional risk factors, such as blood pressure, blood lipids, glucose tolerance and insulin resistance, metabolic syndrome, and overweight and obesity. Evidence from epidemiologic studies suggests that the preventive effects of PA may be achieved by 150 minutes of moderate PA a week, while increases in the intensity and volume of exercise lead to further health benefits. This dose–response gradient is curvilinear, with the largest gains from the first hour of weekly exercise. However, although much progress has been made in this field, existing studies performed on human subjects do not clearly show what type, intensity, and duration of exercise is most beneficial to cardiovascular fitness and metabolic optimization. Animal-based exercise studies may provide more information and help to elucidate the abilities of different training regimens to reduce the risk of CVD.

Acute Effect of High-Intensity Eccentric Exercise on Vascular Endothelial Function in Young Men

Choi, Y, Akazawa, N, Zempo-Miyaki, A, Ra, S-G, Shiraki, H, Ajisaka, R, and Maeda, S. Acute effect of high-intensity eccentric exercise on vascular endothelial function in young men. J Strength Cond Res 30(8): 2279-2285, 2016-Increased central arterial stiffness is as an independent risk factor for cardiovascular disease. Evidence regarding the effects of high-intensity resistance exercise on vascular endothelial function and central arterial stiffness is conflicting. The purpose of this study was to examine the effects of acute high-intensity eccentric exercise on vascular endothelial function and central arterial stiffness. We evaluated the acute changes in endothelium-dependent flow-mediated dilation (FMD), low-flow-mediated constriction (L-FMC), and arterial stiffness after high-intensity eccentric exercise. Seven healthy, sedentary men (age, 24 ± 1 year) performed maximal eccentric elbow flexor exercise using their nondominant arm. Before and 45 minutes after eccentric exercise, carotid arterial compliance and brachial artery FMD and L-FMC in the nonexercised arm were measured. Carotid arterial compliance was significantly decreased, and β-stiffness index significantly increased after eccentric exercise. Brachial FMD was significantly reduced after eccentric exercise, whereas there was no significant difference in brachial L-FMC before and after eccentric exercise. A positive correlation was detected between change in arterial compliance and change in FMD (r = 0.779; p ≤ 0.05), and a negative correlation was detected between change in β-stiffness index and change in FMD (r = -0.891; p < 0.01) with eccentric exercise. In this study, acute high-intensity eccentric exercise increased central arterial stiffness; this increase was accompanied by a decrease in endothelial function caused by reduced endothelium-dependent vasodilation but not by a change in endothelium-dependent vasoconstriction.

Endurance Training Intensity Does Not Mediate Interference to Maximal Lower-Body Strength Gain during Short-Term Concurrent Training

We determined the effect of concurrent training incorporating either high-intensity interval training (HIT) or moderate-intensity continuous training (MICT) on maximal strength, counter-movement jump (CMJ) performance, and body composition adaptations, compared with single-mode resistance training (RT). Twenty-three recreationally-active males (mean ± SD: age, 29.6 ± 5.5 y; V˙O2peak, 44 ± 11 mL kg⁻¹·min⁻¹) underwent 8 weeks (3 sessions·wk⁻¹) of either: (1) HIT combined with RT (HIT+RT group, n = 8), (2) work-matched MICT combined with RT (MICT+RT group, n = 7), or (3) RT performed alone (RT group, n = 8). Measures of aerobic capacity, maximal (1-RM) strength, CMJ performance and body composition (DXA) were obtained before (PRE), mid-way (MID), and after (POST) training. Maximal (one-repetition maximum [1-RM]) leg press strength was improved from PRE to POST for RT (mean change ± 90% confidence interval; 38.5 ± 8.5%; effect size [ES] ± 90% confidence interval; 1.26 ± 0.24; P < 0.001), HIT+RT (28.7 ± 5.3%; ES, 1.17 ± 0.19; P < 0.001), and MICT+RT (27.5 ± 4.6%, ES, 0.81 ± 0.12; P < 0.001); however, the magnitude of this change was greater for RT vs. both HIT+RT (7.4 ± 8.7%; ES, 0.40 ± 0.40) and MICT+RT (8.2 ± 9.9%; ES, 0.60 ± 0.45). There were no substantial between-group differences in 1-RM bench press strength gain. RT induced greater changes in peak CMJ force vs. HIT+RT (6.8 ± 4.5%; ES, 0.41 ± 0.28) and MICT+RT (9.9 ± 11.2%; ES, 0.54 ± 0.65), and greater improvements in maximal CMJ rate of force development (RFD) vs. HIT+RT (24.1 ± 26.1%; ES, 0.72 ± 0.88). Lower-body lean mass was similarly increased for RT (4.1 ± 2.0%; ES; 0.33 ± 0.16; P = 0.023) and MICT+RT (3.6 ± 2.4%; ES; 0.45 ± 0.30; P = 0.052); however, this change was attenuated for HIT+RT (1.8 ± 1.6%; ES; 0.13 ± 0.12; P = 0.069). We conclude that concurrent training incorporating either HIT or work-matched MICT similarly attenuates improvements in maximal lower-body strength and indices of CMJ performance compared with RT performed alone. This suggests endurance training intensity is not a critical mediator of interference to maximal strength gain during short-term concurrent training.

Relative lower body circumferences are associated with the prevalence of metabolic syndrome and arterial stiffness

Body circumference is a known health-related factor. This cross-sectional study aimed to investigate the associations of relative lower body circumferences with metabolic syndrome (MetS) and arterial stiffness (AS) in 684 men aged > 40 (mean, 54.6 ± 8.5) years. Participants were measured for waist, thigh, and calf circumferences; underwent blood tests and blood pressure measurements to detect MetS; and received brachial ankle pulse wave velocity measurements to measure AS. The waist-to-thigh, waist-to-calf, and thigh-to-calf circumferences were calculated and classified into quartiles. Age-adjusted multiple logistic regression models were used to assess the associations between the circumference ratios and AS vs. non-AS and MetS vs. non-MetS (systolic and diastolic blood pressure, triglycerides, high-density lipoprotein cholesterol, and fasting plasma glucose). The mean body mass index was 24.9 ± 2.8 kg/m2; the mean waist, thigh, and calf circumferences were 87.4 ± 7.6, 53.8 ± 4.2, and 36.4 ± 2.7 cm, respectively. Compared to the lowest quartiles, participants in waist-to-thigh circumference quartiles 3 (odds ratio [OR] = 3.195, 95% confidence interval [CI] = 1.825-5.594, p < 0.001) and 4 (OR = 4.755, 95% CI = 2.715-8.325, p < 0.001), and participants in waist-to-calf circumference quartiles 2 (OR = 2.511, 95% CI = 1.397-4.511, p = 0.002), 3 (OR = 3.929, 95% CI = 2.076-7.435, p < 0.001), and 4 (OR = 5.298, 95% CI = 2.847-9.858, p < 0.001) had significantly greater risks of MetS; participants in waist-to-calf circumference quartile 4 (OR = 2.481, 95% CI = 1.477-4.167, p < 0.001) and participants in waist-to-calf circumference quartile 4 (OR = 1.763, 95% CI = 1.088-2.856, p = 0.021) had a significantly greater risk of AS, indicating that age-adjusted relative lower body circumferences associate with MetS and AS. Large thigh and calf circumferences may indicate reduced risks for cardiovascular disease.

The effects of resistance exercise training on arterial stiffness in metabolic syndrome

PURPOSE

Arterial stiffness is a strong independent risk factor for cardiovascular disease and is elevated in individuals with metabolic syndrome (MetS). Resistance training is a popular form of exercise that has beneficial effects on muscle mass, strength, balance and glucose control. However, it is unknown whether resistance exercise training (RT) can lower arterial stiffness in patients with MetS. Thus, the aim of this study was to examine whether a progressive RT program would improve arterial stiffness in MetS.

METHODS

A total of 57 subjects (28 healthy sedentary subjects; 29 MetS) were evaluated for arterial structure and function, including pulse wave velocity (cfPWV: arterial stiffness), before and after an 8-week period of RT or continuation of sedentary lifestyle.

RESULTS

We found that 8 weeks of progressive RT increased skeletal muscle strength in both Con and MetS, but did not change arterial stiffness in either MetS (cfPWV; Pre 7.9 ± 0.4 m/s vs. Post 7.7 ± 0.4 m/s) or healthy controls (cfPWV; Pre 6.9 ± 0.3 m/s vs. Post 7.0 ± 0.3 m/s). However, when cfPWV is considered as a continuous variable, high baseline measures of cfPWV tended to show a decrease in cfPWV following RT.

CONCLUSION

Eight weeks of progressive RT did not decrease the group mean values of arterial stiffness in individuals with MetS or healthy controls.

Aerobic or Resistance Training and Pulse Wave Velocity in Kidney Transplant Recipients: A 12-Week Pilot Randomized Controlled Trial (the Exercise in Renal Transplant [ExeRT] Trial)

BACKGROUND

Cardiovascular disease remains the leading cause of death in kidney transplant recipients. This pilot study examined the potential effect of aerobic training or resistance training on vascular health and indexes of cardiovascular risk in kidney transplant recipients.

STUDY DESIGN

Single-blind, randomized, controlled, parallel trial.

SETTING & PARTICIPANTS

60 participants (mean age, 54 years; 34 men) were randomly assigned to aerobic training (n=20), resistance training (n=20), or usual care (n=20). Participants were included if they had a kidney transplant within 12 months prior to baseline assessment. Patients were excluded if they had unstable medical conditions or had recently started regular exercise.

INTERVENTION

Aerobic training and resistance training were delivered 3 days per week for a 12-week period. The usual-care group received standard care.

OUTCOMES & MEASUREMENTS

Pulse wave velocity, peak oxygen uptake (Vo2peak), sit-to-stand 60, isometric quadriceps force, and inflammatory biomarkers were assessed at 0 and 12 weeks.

RESULTS

The anticipated 60 participants were recruited within 12 months. 46 participants completed the study (aerobic training, n=13; resistance training, n=13; and usual care, n=20), resulting in a 23% attrition rate. Analyses of covariance, adjusted for baseline values, age, and dialysis vintage pretransplantation, revealed significant mean differences between aerobic training and usual care in pulse wave velocity of -2.2±0.4 (95% CI, -3.1 to -1.3) m/s (P<0.001) and between resistance training and usual care of -2.6±0.4 (95% CI, -3.4 to -1.7) m/s (P<0.001) at 12 weeks. Secondary analyses indicated significant improvements in Vo2peak in the aerobic training group and in Vo2peak, sit-to-stand 60, and isometric muscle force in the resistance training group compared with usual care at 12 weeks. There were no reported adverse events, cardiovascular events, or hospitalizations as a result of the intervention.

LIMITATIONS

Pilot study, small sample size, no measure of endothelial function.

CONCLUSIONS

Both aerobic training and resistance training interventions appear to be feasible and clinically beneficial in this patient population.

Effect of resistance training on microvascular density and eNOS content in skeletal muscle of sedentary men

OBJECTIVE

The effects of RT on muscle mass, strength, and insulin sensitivity are well established, but the underlying mechanisms are only partially understood. The main aim of this study was to investigate whether RT induces changes in endothelial enzymes of the muscle microvasculature, which would increase NO bioavailability and could contribute to improved insulin sensitivity.

METHODS

Eight previously sedentary males (age 20 ± 0.4 years, BMI 24.5 ± 0.9 kg/m(2) ) completed six weeks of RT 3x/week. Muscle biopsies were taken from the m. vastus lateralis and microvascular density; and endothelial-specific eNOS content, eNOS Ser(1177) phosphorylation, and NOX2 content were assessed pre- and post-RT using quantitative immunofluorescence microscopy. Whole-body insulin sensitivity (measured as Matsuda Index), microvascular Kf (functional measure of the total available endothelial surface area), and arterial stiffness (AIx, central, and pPWV) were also measured.

RESULTS

Measures of microvascular density, microvascular Kf , microvascular eNOS content, basal eNOS phosphorylation, and endothelial NOX2 content did not change from pre-RT to post-RT. RT increased insulin sensitivity (p < 0.05) and reduced resting blood pressure and AIx (p < 0.05), but did not change central or pPWV.

CONCLUSIONS

RT did not change any measure of muscle microvascular structure or function.

Effects of acute and chronic exercise in patients with essential hypertension: benefits and risks

The importance of regular physical activity in essential hypertension has been extensively investigated over the last decades and has emerged as a major modifiable factor contributing to optimal blood pressure control. Aerobic exercise exerts its beneficial effects on the cardiovascular system by promoting traditional cardiovascular risk factor regulation, as well as by favorably regulating sympathetic nervous system (SNS) activity, molecular effects, cardiac, and vascular function. Benefits of resistance exercise need further validation. On the other hand, acute exercise is now an established trigger of acute cardiac events. A number of possible pathophysiological links have been proposed, including SNS, vascular function, coagulation, fibrinolysis, and platelet function. In order to fully interpret this knowledge into clinical practice, we need to better understand the role of exercise intensity and duration in this pathophysiological cascade and in special populations. Further studies in hypertensive patients are also warranted in order to clarify the possibly favorable effect of antihypertensive treatment on exercise-induced effects.

Cardiac rehabilitation improves coronary endothelial function in patients with heart failure due to dilated cardiomyopathy: A positron emission tomography study

BACKGROUND

Endothelial dysfunction is common in patients with heart failure and is associated with poor clinical outcome. Cardiac rehabilitation is able to enhance peripheral endothelial function but its impact on coronary vasomotion remains unknown. We aimed to evaluate the effect of cardiac rehabilitation on coronary vasomotion in patients with heart failure.

METHOD

We prospectively enrolled 29 clinically stable heart failure patients from non-ischaemic dilated cardiomyopathy and without coronary risk factors. Myocardial blood flow was quantified using (15)-O water positron emission tomography at rest and during a cold pressor test, before and after 12 weeks of cardiac rehabilitation and optimization of medical therapy.

RESULTS

Rest myocardial blood flow was significantly improved after the completion of rehabilitation compared to baseline (1.31 ± 0.38 mL/min/g vs. 1.16 ± 0.41 mL/min/g, p = 0.04). The endothelium-related change in myocardial blood flow from rest to cold pressor test and the percentage of myocardial blood flow increase during the cold pressor test were both significantly improved after cardiac rehabilitation (respectively from -0.03 ± 0.22 mL/min/g to 0.19 ± 0.22 mL/min/g, p < 0.001 and from 101.5 ± 16.5% to 118.3 ± 24.4%, p < 0.001). Left ventricular ejection fraction, plasma levels of brain natriuretic peptide, maximal oxygen consumption and the Minnesota Living with Heart Failure Questionnaire score were also significantly improved. The improvement was not related to uptitration of medical therapy.

CONCLUSIONS

Coronary endothelial function is altered in patients with heart failure due to non-ischaemic dilated cardiomyopathy. In these patients, cardiac rehabilitation significantly improves coronary vasomotion.

Age, aerobic fitness, and cerebral perfusion during exercise: role of carbon dioxide

Middle cerebral artery mean velocity (MCAvmean) is attenuated with increasing age both at rest and during exercise. The aim of this study was to determine the influence of the age-dependent reduction in arterial Pco2 (PaCO2) and physical fitness herein. We administered supplemental CO2 (CO2 trial) or no additional gas (control trial) to the inspired air in a blinded and randomized manner, and assessed middle cerebral artery mean flow velocity during graded exercise in 1) 21 young [Y; age 24 ± 3 yr (±SD)] volunteers of whom 11 were trained (YT) and 10 considered untrained (YUT), and 2) 17 old (O; 66 ± 4 yr) volunteers of whom 8 and 9 were considered trained (OT) and untrained (OUT), respectively. A resting hypercapnic reactivity test was also performed. MCAvmean and PaCO2 were lower in O [44.9 ± 3.1 cm/s and 30 ± 1 mmHg (±SE)] compared with Y (59.3 ± 2.3 cm/s and 34 ± 1 mmHg, P < 0.01) at rest, independent of aerobic fitness level. The age-related decreases in MCAvmean and PaCO2 persisted during exercise. Supplemental CO2 reduced the age-associated decline in MCAvmean by 50%, suggesting that PaCO2 is a major component in the decline. On the other hand, relative hypercapnic reactivity was neither influenced by age ( P = 0.46) nor aerobic fitness ( P = 0.36). Although supplemental CO2 attenuated exercise-induced reduction in cerebral oxygenation (near-infrared spectroscopy), this did not influence exercise performance. In conclusion, PaCO2 contributes to the age-associated decline in MCAvmean at rest and during exercise; however exercise capacity did not diminish this age effect.

Lack of age-related increase in carotid artery wall viscosity in cardiorespiratory fit men

OBJECTIVES

Age-related arterial stiffening and reduction of arterial elasticity are attenuated in individuals with high levels of cardiorespiratory fitness. Viscosity is another mechanical characteristic of the arterial wall; however, the effects of age and cardiorespiratory fitness have not been determined. We examined the associations among age, cardiorespiratory fitness and carotid arterial wall viscosity.

METHODS

A total of 111 healthy men, aged 25-39 years (young) and 40-64 years (middle-aged), were divided into either cardiorespiratory fit or unfit groups on the basis of peak oxygen uptake. The common carotid artery was measured noninvasively by tonometry and automatic tracking of B-mode images to obtain instantaneous pressure and diameter hysteresis loops, and we calculated the effective compliance, isobaric compliance and viscosity index.

RESULTS

In the middle-aged men, the viscosity index was larger in the unfit group than in the fit group (2533 vs. 2018 mmHg·s/mm, respectively: P<0.05), but this was not the case in the young men. In addition, effective and isobaric compliance were increased, and viscosity index was increased with advancing age, but these parameters were unaffected by cardiorespiratory fitness level.

CONCLUSION

These results suggest that the wall viscosity in the central artery is increased with advancing age and that the age-associated increase in wall viscosity may be attenuated in cardiorespiratory fit men.

Resting heart rate and the association of physical fitness with carotid artery stiffness

BACKGROUND

Physical fitness is known to influence arterial stiffness. Resting heart rate is reduced by exercise and positively associated with arterial stiffness. This study aimed to investigate the role of resting heart rate in the relationship of physical fitness with arterial stiffness.

METHODS

Subjects were 2,328 young adults from the Childhood Determinants of Adult Health study. Cardiorespiratory fitness was estimated as physical work capacity at a heart rate of 170 bpm. Muscular strength was estimated by hand-grip (both sides), shoulder (pull and push), and leg strength. Arterial stiffness was measured using carotid ultrasound.

RESULTS

Arterial stiffness was negatively associated with cardiorespiratory fitness (men P < 0.001; women P = 0.002), and positively associated with muscular strength in women (P = 0.002) but not in men. Resting heart rate was positively associated with arterial stiffness (P < 0.001 both men and women). Adjustment for resting heart rate reduced the inverse association of arterial stiffness with cardiorespiratory fitness by 93.7% (men) and 67.6% (women) but substantially increased the positive association of arterial stiffness with muscular strength among women and revealed a positive association of arterial stiffness with muscular strength among men. These findings were independent of body size, blood pressure, biochemical markers, socioeconomic status, smoking, and alcohol consumption.

CONCLUSIONS

Our findings attribute a key intermediary role for resting heart rate in the relationship between fitness and arterial stiffness, whereby higher cardiorespiratory fitness may reduce arterial stiffness mainly through resting heart rate, and higher muscular strength might have deleterious effects on arterial stiffness that are partially offset by lower resting heart rate.

Vascular adaptations to low-load resistance training with and without blood flow restriction

PURPOSE

To examine the effects of low-load knee extensor training to fatigue with and without blood flow restriction (BFR) on calf vascular conductance, calf venous compliance, and peripheral arterial stiffness in middle-aged individuals.

METHODS

Eleven men (55 ± 8 years) and five post-menopausal women (57 ± 5 years) completed 6 weeks of unilateral knee extensor training with one limb exercising with BFR (BFR limb) and the contralateral limb exercising without BFR (free flow, FF limb). Before and after the training, femoral pulse wave velocity (PWV), calf blood flow (normalized as conductance), and calf venous compliance were measured in each limb.

RESULTS

PWV increased following training in both limbs (main effect of time, p = 0.036; BFR limb 8.9 ± 0.8 vs. 9.5 ± 0.9 m/s, FF limb 9.0 ± 1.2 vs. 9.0 ± 1.1; Pre vs. Post). Calf blood flow increased (p = 0.026) in the FF limb (25.0 ± 7.0 vs. 31.8 ± 12.0 flow/mmHg; Pre vs. Post) but did not change (p = 0.831) in the BFR limb (29.1 ± 11.3 vs. 28.7 ± 11.5 flow/mmHg; Pre vs. Post). Calf venous compliance did not change in either limb following training.

CONCLUSIONS

These results suggest low-load BFR resistance training to fatigue elicits small increases in peripheral arterial stiffness without eliciting concomitant changes in venous compliance. In addition, unlike low-load knee extensor training without BFR, training with BFR did not enhance calf blood flow.

Arterial compliance and stiffness following low-intensity resistance exercise

PURPOSE

Although acute high-intensity resistance exercise to exhaustion decreases arterial compliance and increases arterial stiffness, the effect of low-intensity resistance exercise (LRE) to exhaustion on arterial compliance and stiffness remains unknown. The present study investigated the acute effects of LRE on arterial compliance and stiffness.

METHODS

Ten healthy individuals (age 26 ± 5 years) performed LRE (40% of 1 repetition maximum) and control (CON: seated rest in the exercise room) trials on separate days in a randomized controlled crossover fashion. The LRE comprised three sets of bench presses to exhaustion with an inter-set rest period of 2 min. In the CON trial, LRE was not performed. Carotid arterial compliance, the β-stiffness index (via simultaneous B-mode ultrasound and applanation tonometry), carotid and brachial blood pressure and heart rate were measured before and at 30 and 60 min after both trials.

RESULTS

Carotid arterial compliance and the β-stiffness index significantly increased and decreased, respectively (both P < 0.05), at 30 and 60 min after the LRE trials, but neither significantly differed after the CON trials. Carotid and brachial blood pressure and heart rate did not change at 30 and 60 min after both trials from baseline.

CONCLUSION

These results suggest that LRE acutely increases arterial compliance and decreases arterial stiffness.

Effects of resistance training on central blood pressure in obese young men

Central blood pressure is a predictor of the risk of cardiovascular disease (CVD), and the effects of resistance training (RT) on central blood pressure are largely unknown. This study explored the effects of high-intensity RT on central blood pressure, indices of arterial stiffness and wave reflection and inflammatory/atherogenic markers in overweight or obese, sedentary young men. Thirty-six participants were randomized to RT (12 weeks of training, 3/wk, n=28) or control groups (C, 12 weeks of no training, n=8) and assessed for changes in central and brachial blood pressures, augmentation index (AIx), carotid-femoral pulse wave velocity (cfPWV), carotid intima-media thickness (cIMT), body composition, lipids and inflammatory/atherogenic markers. High-intensity RT resulted in decreased central and brachial systolic/diastolic blood pressures (all P0.03), despite not altering AIx (P=0.34) or cfPWV (P=0.43). The vascular endothelial growth factor increased (P=0.03) after RT, without any change in cIMT, C-reactive protein, oxidized LDL (oxLDL) or other inflammatory markers (all P0.1). Changes in the central systolic blood pressure (cSBP) were positively correlated with changes in oxLDL (r=0.42, P=0.03) and soluble E-selectin (r=0.41, P=0.04). In overweight/obese young men, high-intensity RT decreases cSBP, independently of weight loss and changes in arterial stiffness. The cardioprotective effects of RT may be related to effects on central blood pressure.

Exercise training reduces peripheral arterial stiffness and myocardial oxygen demand in young prehypertensive subjects

BACKGROUND

Large artery stiffness is a major risk factor for the development of hypertension and cardiovascular disease. Persistent prehypertension accelerates the progression of arterial stiffness.

METHODS

Forty-three unmedicated prehypertensive (systolic blood pressure (SBP) = 120-139 mm Hg or diastolic blood pressure (DBP) = 80-89 mm Hg) men and women and 15 normotensive time-matched control subjects (NMTCs; n = 15) aged 18-35 years of age met screening requirements and participated in the study. Prehypertensive subjects were randomly assigned to a resistance exercise training (PHRT; n = 15), endurance exercise training (PHET; n = 13) or time-control group (PHTC; n = 15). Treatment groups performed exercise training 3 days per week for 8 weeks. Pulse wave analysis, pulse wave velocity (PWV), and central and peripheral blood pressures were evaluated before and after exercise intervention or time-matched control.

RESULTS

PHRT and PHET reduced resting SBP by 9.6±3.6mm Hg and 11.9±3.4mm Hg, respectively, and DBP by 8.0±5.1mm Hg and 7.2±3.4mm Hg, respectively (P < 0.05). PHRT and PHET decreased augmentation index (AIx) by 7.5% ± 2.8% and 8.1% ± 3.2% (P < 0.05), AIx@75 by 8.0% ± 3.2% and 9.2% ± 3.8% (P < 0.05), and left ventricular wasted pressure energy, an index of extra left ventricular myocardial oxygen requirement due to early systolic wave reflection, by 573±161 dynes s/cm(2) and 612±167 dynes s/cm(2) (P < 0.05), respectively. PHRT and PHET reduced carotid-radial PWV by 1.02±0.32 m/sec and 0.92±0.36 m/sec (P < 0.05) and femoral-distal PWV by 1.04±0.31 m/sec and 1.34±0.33 m/sec (P < 0.05), respectively. No significant changes were observed in the time-control groups.

CONCLUSIONS

This study suggests that both resistance and endurance exercise alone effectively reduce peripheral arterial stiffness, central blood pressures, augmentation index, and myocardial oxygen demand in young prehypertensive subjects.

Potential benefits of exercise on blood pressure and vascular function

Physical activity seems to enhance cardiovascular fitness during the course of the lifecycle, improve blood pressure, and is associated with decreased prevalence of hypertension and coronary heart disease. It may also delay or prevent age-related increases in arterial stiffness. It is unclear if specific exercise types (aerobic, resistance, or combination) have a better effect on blood pressure and vascular function. This review was written based on previous original articles, systematic reviews, and meta-analyses indexed on PubMed from years 1975 to 2012 to identify studies on different types of exercise and the associations or effects on blood pressure and vascular function. In summary, aerobic exercise (30 to 40 minutes of training at 60% to 85% of predicted maximal heart rate, most days of the week) appears to significantly improve blood pressure and reduce augmentation index. Resistance training (three to four sets of eight to 12 repetitions at 10 repetition maximum, 3 days a week) appears to significantly improve blood pressure, whereas combination exercise training (15 minutes of aerobic and 15 minutes of resistance, 5 days a week) is beneficial to vascular function, but at a lower scale. Aerobic exercise seems to better benefit blood pressure and vascular function.

Beyond medications and diet: alternative approaches to lowering blood pressure: a scientific statement from the american heart association

Many antihypertensive medications and lifestyle changes are proven to reduce blood pressure. Over the past few decades, numerous additional modalities have been evaluated in regard to their potential blood pressure-lowering abilities. However, these nondietary, nondrug treatments, collectively called alternative approaches, have generally undergone fewer and less rigorous trials. This American Heart Association scientific statement aims to summarize the blood pressure-lowering efficacy of several alternative approaches and to provide a class of recommendation for their implementation in clinical practice based on the available level of evidence from the published literature. Among behavioral therapies, Transcendental Meditation (Class IIB, Level of Evidence B), other meditation techniques (Class III, Level of Evidence C), yoga (Class III, Level of Evidence C), other relaxation therapies (Class III, Level of Evidence B), and biofeedback approaches (Class IIB, Level of Evidence B) generally had modest, mixed, or no consistent evidence demonstrating their efficacy. Between the noninvasive procedures and devices evaluated, device-guided breathing (Class IIA, Level of Evidence B) had greater support than acupuncture (Class III, Level of Evidence B). Exercise-based regimens, including aerobic (Class I, Level of Evidence A), dynamic resistance (Class IIA, Level of Evidence B), and isometric handgrip (Class IIB, Level of Evidence C) modalities, had relatively stronger supporting evidence. It is the consensus of the writing group that it is reasonable for all individuals with blood pressure levels >120/80 mm Hg to consider trials of alternative approaches as adjuvant methods to help lower blood pressure when clinically appropriate. A suggested management algorithm is provided, along with recommendations for prioritizing the use of the individual approaches in clinical practice based on their level of evidence for blood pressure lowering, risk-to-benefit ratio, potential ancillary health benefits, and practicality in a real-world setting. Finally, recommendations for future research priorities are outlined.

High-intensity endurance training results in faster vessel-specific rate of vasorelaxation in type 1 diabetic rats

This study examined the effects of 6 weeks of moderate- (MD) and high-intensity endurance training (HD) and resistance training (RD) on the vasorelaxation responsiveness of the aorta, iliac, and femoral vessels in type 1 diabetic (D) rats. Vasorelaxation to acetylcholine was modeled as a mono-exponential function. A potential mediator of vasorelaxation, endothelial nitric oxide synthase (e-NOS) was determined by Western blots. Vessel lumen-to-wall ratios were calculated from H&E stains. The vasorelaxation time-constant (τ) (s) was smaller in control (C) (7.2±3.7) compared to D (9.1±4.4) and it was smaller in HD (5.4±1.5) compared to C, D, RD (8.3±3.7) and MD (8.7±3.8) (p<0.05). The rate of vasorelaxation (%·s⁻¹) was larger in HD (2.7±1.2) compared to C (2.0±1.2), D (2.0±1.5), RD (2.0±1.0), and MD (2.0±1.2) (p<0.05). τ vasorelaxation was smaller in the femoral (6.9±3.7) and iliac (6.9±4.7) than the aorta (9.0±5.0) (p<0.05). The rate of vasorelaxation was progressively larger from the femoral (3.1±1.4) to the iliac (2.0±0.9) and to the aorta (1.3±0.5) (p<0.05). e-NOS content (% of positive control) was greater in HD (104±90) compared to C (71±64), D (85±65), RD (69±43), and MD (76±44) (p<0.05). e-NOS normalized to lumen-to-wall ratio (%·mm⁻¹) was larger in the femoral (11.7±11.1) compared to the aorta (3.2±1.9) (p<0.05). Although vasorelaxation responses were vessel-specific, high-intensity endurance training was the most effective exercise modality in restoring the diabetes-related loss of vascular responsiveness. Changes in the vasoresponsiveness seem to be endothelium-dependent as evidenced by the greater e-NOS content in HD and the greater normalized e-NOS content in the smaller vessels.

Resistance exercise training reduces arterial reservoir pressure in older adults with prehypertension and hypertension

We examined changes in central blood pressure (BP) following resistance exercise training (RET) in men and women with prehypertension and never-treated hypertension. Both Windkessel theory and wave theory were used to provide a comprehensive examination of hemodynamic modulation with RET. Twenty-one participants (age 61±1 years, n=6 male; average systolic blood pressure (SBP)/diastolic blood pressure (DBP)=138/84 mm Hg) were randomized to either 12 weeks of RET (n=11) or an inactive control group. Central BP and augmentation index (AIx) were derived from radial pressure waveforms using tonometry and a generalized transfer function. A novel reservoir-wave separation technique was used to derive excess wave pressure (related to forward and backward traveling waves) and reservoir pressure (related to the capacitance/Windkessel properties of the arterial tree). Wave separation using traditional impedance analysis and aortic flow triangulation was also applied to derive forward wave pressure (Pf) and backward wave pressure (Pb). There was a group-by-time interaction (P<0.05) for central BP as there was a significant ~6 mm Hg reduction in SBP and ~7 mm Hg reduction in DBP following RET with no change in the control condition. There were also group-by-time interactions (P<0.05) for Pf, excess wave pressure and reservoir pressure attributable to reductions in these parameters in the RET group concomitant with slight increases in the control group. There was no change in AIx or Pb (P>0.05). RET may reduce central BP in older adults with hypertension and prehypertension by lowering Pf and reservoir pressure without affecting pressure from wave reflections.

Blood flow restricted exercise and vascular function

It is established that regular aerobic training improves vascular function, for example, endothelium-dependent vasodilatation and arterial stiffness or compliance and thereby constitutes a preventative measure against cardiovascular disease. In contrast, high-intensity resistance training impairs vascular function, while the influence of moderate-intensity resistance training on vascular function is still controversial. However, aerobic training is insufficient to inhibit loss in muscular strength with advancing age; thus, resistance training is recommended to prevent sarcopenia. Recently, several lines of study have provided compelling data showing that exercise and training with blood flow restriction (BFR) leads to muscle hypertrophy and strength increase. As such, BFR training might be a novel means of overcoming the contradiction between aerobic and high-intensity resistance training. Although it is not enough evidence to obtain consensus about impact of BFR training on vascular function, available evidences suggested that BFR training did not change coagulation factors and arterial compliance though with inconsistence results in endothelial function. This paper is a review of the literature on the impact of BFR exercise and training on vascular function, such as endothelial function, arterial compliance, or other potential factors in comparison with those of aerobic and resistance training.

Resistance, aerobic, and combination training on vascular function in overweight and obese adults

The authors investigated the effects of moderate-intensity resistance, aerobic, or combined exercise on blood pressure and arterial stiffness in overweight and obese individuals compared with no exercise. Participants were randomized to 4 groups: control, aerobic, resistance, and combination. Assessments were made at baseline, week 8, and week 12. In participant-designated responders, those in the intervention groups who had improved levels of systolic blood pressure (SBP) or augmentation index (AI), we observed a significant decrease of SBP in aerobic (-4%, P=.027), resistance (-5.1%, P=.04), and combination groups (-6.3%, P=.000) at week 8 and in the combination group (-6.3%, P=.005) at week 12, compared with baseline. AI was significantly lower at week 12 in the aerobic (-12%, P=.047), resistance (-9.5%, P=.036), and combination (-12.7%, P=.003) groups compared with baseline, as well as in the combination group (-10.7%, P=.047) compared with the control group. We did not observe significant changes in SBP, DBP, or AI between the interventions when assessing the entire cohort, although there were significant improvements in a subgroup of responders. Thus, some but not all overweight and obese individuals can improve blood pressure and arterial stiffness by participating in regular combination exercise, decreasing the risk of developing cardiovascular disease.