Resistance training-induced decrease in central arterial compliance is associated with decreased subendocardial viability ratio in healthy young men

The effect of different proximities to failure on arterial stiffness following resistance training protocols matched for volume-load

This study compared acute changes in measures of arterial stiffness (AS) between two resistance training (RT) protocols that were load, volume and rest matched, but differed in intensity of effort. Eleven healthy adults (36.4 ± 6.8 years) performed a RT protocol with high intensity of effort (HE) and a RT protocol with low intensity of effort (LE). The HE protocol consisted of 3 sets of 12 repetitions, while the LE comprised of 6 sets of 6 repetitions. Loading intensity, volume load, and total rest duration were equivalent between the RT sessions. Pulse wave velocity, augmentation index values collected at baseline, immediately post and 15 min post-exercise. HE elicited significantly greater increases in carotid-femoral pulse wave velocity (6.4 ± 0.3 to 7.3 ± 0.5 m/s) when compared to LE (6.6 ± 0.3 to 6.7 ± 0.3 m/s) (p < 0.05). Both HE and LE induced significant increases in augmentation index (13 ± 5.6 to 28.1 ± 9.3%) post exercise (all p < 0.05). These findings demonstrate that RT with a lower intensity of effort attenuate increases in measures of arterial stiffness compared to a RT scheme at higher intensity of effort when volume load and total rest are equalized.

Hemodynamic analysis of blood flow restriction training: a systematic review

Blood Flow Restriction Training (BFRT) is a low-load training technique that involves applying pressure to partially restrict arterial blood flow while occluding venous return. Despite its growing popularity, there is still no consensus on how combining BFRT with resistance or aerobic training influences hemodynamic responses, or on the safest and most effective methods for implementing it. This review aims to systematically identify the effects of BFRT on hemodynamic parameters. A systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement guidelines. The Chinese literature search was performed in the China National Knowledge Infrastructure (CNKI) database. English literature search was conducted in the Web of Science, PubMed, and Google Scholar databases. The studies included human subjects, the outcome indicators included hemodynamic evaluation indicators, and only randomized controlled trials and randomized crossover trials were considered. Non-Chinese or English literature, duplicate studies, and those with missing data were excluded. The adapted STROBE checklist was used to assess the risk of bias, 44 articles were included in this review. Results indicated that BFRT has increased heart rate and blood lactate levels, while its effect on blood oxygen saturation varies. Additionally, BFRT significantly enhances cardiac output but may either have no significant effect or cause a decrease in stroke volume. Furthermore, BFRT improves pulse wave velocity from the femur to the posterior tibia, suggesting a positive influence on cardiovascular function. BFRT induces changes in arterial structure and function, with these indicators interacting to produce both positive and negative effects on cardiovascular health. The primary mechanisms by which BFRT influences hemodynamics include the activation of the sympathetic and vagus nerves, as well as the regulation of chemical mediators in body fluids that modulate cardiovascular function. Convenient, economical, non-invasive, and easily measurable hemodynamic indicators are expected to become an efficient tool for evaluating the effects of exercise training. Further research is needed to establish the optimal compression thresholds and durations for different populations and exercise types, as well as to assess the long-term impact of BFRT on hemodynamic parameters.

The correlation between subendocardial viability ratio and the degree of coronary artery stenosis in patients with coronary heart disease and its predictive value for the incidence of short-term cardiovascular events

OBJECTIVES

This study aimed to analyze the ability of subendocardial viability ratio (SEVR) to predict the degree of coronary artery stenosis and the relationship between SEVR and the incidence of short-term cardiovascular endpoint events.

METHOD

The indexes of 243 patients with chest pain were collected.. Binary logistic regression analyses were performed using the dichotomous outcome of high and non-high SYNTAX scores. Receiver operating characteristic curves were employed to comparatively analyze the diagnostic efficiencies of the indices and models. A survival analysis combined with the Cox regression analysis was performed using the Kaplan-Meier method to understand the relationship between the SEVR and the incidence of cardiovascular events within 1 year in patients with coronary heart disease (CHD).

RESULTS

SEVR was significantly lower ( P  < 0.05) in the high-stenosis group than control and low-stenosis groups. The diagnostic efficacy of SEVR [area under the curve (AUC) = 0.861] was better than those of age (AUC = 0.745), ABI (AUC = 0.739), and AIx@HR75 (AUC = 0.659). The cutoff SEVR was 1.105. In patients with confirmed CHD who had been discharged from the hospital for 1 year, only SEVR affected survival outcomes (hazard ratio = 0.010; 95% confidence interval: 0.001-0.418; P  = 0.016).

CONCLUSION

A significant decrease in SEVR predicted severe coronary artery stenosis, with a cutoff value of 1.105 and an accuracy of 0.861. In patients with CHD, the lower the SEVR, the higher was the rate of cardiovascular events at 1 year after hospital discharge.

Advanced cardiovascular physiology in an individual with type 1 diabetes after 10-year ketogenic diet

Adults with type 1 diabetes (T1D) have an elevated risk for cardiovascular disease (CVD) compared with the general population. HbA1c is the primary modifiable risk factor for CVD in T1D. Fewer than 1% of patients achieve euglycemia (<5.7% HbA1c). Ketogenic diets (KD; ≤50 g carbohydrate/day) may improve glycemia and downstream vascular dysfunction in T1D by reducing HbA1c and insulin load. However, there are concerns regarding the long-term CVD risk from a KD. Therefore, we compared data collected in a 60-day window in an adult with T1D on exogenous insulin who consumed a KD for 10 years versus normative values in those with T1D (T1D norms). The participant achieved euglycemia with an HbA1c of 5.5%, mean glucose of 98 [5] mg/dL (median [interquartile range]), 90 [11]% time-in-range 70-180 mg/dL (T1D norms: 1st percentile for all), and low insulin requirements of 0.38 ± 0.03 IU/kg/day (T1D norms: 8th percentile). Seated systolic blood pressure (SBP) was 113 mmHg (T1D norms: 18th percentile), while ambulatory awake SBP was 132 ± 15 mmHg (T1D target: <130 mmHg), blood triglycerides were 69 mg/dL (T1D norms: 34th percentile), low-density lipoprotein was 129 mg/dL (T1D norms: 60th percentile), heart rate was 56 beats/min (T1D norms: >1SD below the mean), carotid-femoral pulse wave velocity was 7.17 m/s (T1D norms: lowest quartile of risk), flow-mediated dilation was 12.8% (T1D norms: >1SD above mean), and cardiac vagal baroreflex gain was 23.5 ms/mmHg (T1D norms: >1SD above mean). Finally, there was no indication of left ventricular diastolic dysfunction from echocardiography. Overall, these data demonstrate below-average CVD risk relative to T1D norms despite concerns regarding the long-term impact of a KD on CVD risk.NEW & NOTEWORTHY Adults with type 1 diabetes (T1D) have a 10-fold higher risk for cardiovascular disease (CVD) compared with the general population. We assessed cardiovascular health metrics in an adult with T1D who presented with a euglycemic HbA1c after following a ketogenic diet for the past 10 years. Despite concerns about the ketogenic diet increasing CVD risk, the participant exhibited below-average CVD risk relative to others with T1D when considering all outcomes together.

The relationship between combat-related traumatic amputation and subclinical cardiovascular risk

BACKGROUND

The relationship between acute combat-related traumatic injury (CRTI) to coronary flow reserve (CFR) and subclinical cardiovascular risk have not been examined and was the primary aim of this study.

METHODS AND RESULTS

UK combat veterans from the ADVANCE cohort study (UK-Afghanistan War 2003-14) with traumatic limb amputations were compared to injured non-amputees and to a group of uninjured veterans from the same conflict. Subclinical cardiovascular risk measures included fasted blood atherogenic index of plasma (AIP), triglyceride-glucose index (TyG; insulin resistance), the neutrophil-lymphocyte ratio (NLR) and high-sensitivity C-reactive protein (hs-CRP; vascular inflammation), body mass index (BMI) and visceral fat volume (dual-energy X-ray absorptiometry) and 6-min walk distance (6MWD; physical performance). The subendocardial viability ratio (SEVR), to estimate CFR, was calculated using arterial pulse waveform analysis (Vicorder device). In total 1144 adult male combat veterans were investigated, comprising 579 injured (161 amputees, 418 non-amputees) and 565 uninjured men. AIP, TyG, NLR, hs-CRP, BMI, total body fat and visceral fat volume were significantly higher and the SEVR and 6MWD significantly lower in the amputees versus the injured-non-amputees and uninjured groups. The SEVR was lowest in those with above knee and multiple limb amputations. CRTI (ExpB 0.96; 95% CI 0.94-0.98: p < 0.0001) and amputation (ExpB 0.94: 95% CI 0.91-0.97: p < 0.0001) were independently associated with lower SEVR after adjusting for age, rank, ethnicity and time from injury.

CONCLUSION

CRTI, traumatic amputation and its worsening physical deficit are associated with lower coronary flow reserve and heightened subclinical cardiovascular risk.

Eccentric exercise improves myocardial oxygen supply/demand balance with decelerating aortic diastolic pressure decay: The acute and chronic studies

Both eccentric (ECC) and concentric (CON) exercises improve energy expenditure and blood lipid profile. Although ECC exercise has a more beneficial effect on these factors than CON exercise, its benefits on vital organs are still unclear. This study investigated the mode-of-action-dependent effects on myocardial perfusion index. Seventeen healthy men (age: 26 ± 5 years) were randomly enrolled in CON (n = 9) and ECC (n = 8) groups. Transient exercise and regular training (three-day a week for 4-week) included bicep curl comprising 5-set of 10-repetition, each using 75% one-repetition maximum concentric loading. The ECC group performed one-repetition of ECC for 3-s and CON for 1-s, while the CON group performed one-repetition of CON for 3-s and ECC for 1-s. All participants were assessed for subendocardial viability ratio (SEVR, myocardial perfusion index) and aortic diastolic pressure decay. Before study, these were found to be same for both groups. Transient (ΔSEVR: 20.3 ± 13.3%, p = 0.01; Δdecay: -0.07 ± 0.02 s^-1, p < .001) and regular (ΔSEVR: 18.5 ± 12.8%, p = .001; Δdecay: -0.06 ± 0.05 s^-1, p = .004) ECC (but not CON) exercises significantly increased SEVR and decelerated decay. Increased SEVR with ECC exercise was associated with decelerated decay (transient ECC: r² = 0.56, 95% confidence interval [CI] = -0.95 to -0.10, p = .03; regular ECC: r² = 0.53, 95% CI = -0.95 to -0.05, p = .04). These findings suggest that ECC exercise improves myocardial perfusion and diastolic pressure contour is involved in physiological mechanisms.

Sports activities at a young age decrease hypertension risk-The J-Fit+ study

This study aimed to assess (1) blood pressure between young, current athletes, and non-athletes early in life; (2) hypertension prevalence between former athletes and the general population later in life; and (3) understand the mechanisms between exercise training and hypertension risks in the form of DNA methylation. Study 1: A total of 354 young male participants, including current athletes, underwent blood pressure assessment. Study 2: The prevalence of hypertension in 1269 male former athletes was compared with that in the Japanese general population. Current and former athletes were divided into three groups: endurance-, mixed-, and sprint/power-group. Study 3: We analyzed the effect of aerobic- or resistance-training on DNA methylation patterns using publicly available datasets to explore the possible underlying mechanisms. In young, current athletes, the mixed- and sprint/power-group exhibited higher systolic blood pressure, and all groups exhibited higher pulse pressure than non-athletes. In contrast, the prevalence of hypertension in former athletes was significantly lower in all groups than in the general population. Compared to endurance-group (reference), adjusted-hazard ratios for the incidence of hypertension among mixed- and sprint/power-group were 1.24 (0.87-1.84) and 1.50 (1.04-2.23), respectively. Moreover, aerobic- and resistance-training commonly modified over 3000 DNA methylation sites in skeletal muscle, and these were suggested to be associated with cardiovascular function-related pathways. These findings suggest that the high blood pressure induced by exercise training at a young age does not influence the development of future hypertension. Furthermore, previous exercise training experiences at a young age could decrease the risk of future 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.

Circulating fibroblast growth factor 21 links hemodynamics with kidney function in middle-aged and older adults: A mediation analysis

Altered hemodynamics are commonly observed in individuals with declining renal function; however, the pathophysiological mechanisms linking renal dysfunction and hemodynamics have not been fully elucidated. Fibroblast growth factor 21 (FGF21), which upregulates sympathetic nerve activity, can alter systemic hemodynamics, and its level can increase as renal function declines. This study aimed to determine the associations among circulating FGF21 levels, hemodynamics, and renal function in middle-aged and older adults. In a total of 272 middle-aged and older adults (age range: 46-83 years), estimated glomerular filtration rate (eGFR), hemodynamics (brachial and aortic blood pressure and aortic pulse wave velocity [PWV]), and serum FGF21 levels were measured. For mediation analysis, hemodynamic parameters were entered as outcomes. eGFR or log-transformed urinary albumin and creatinine ratio (UACR) and log-transformed serum FGF21 levels were set as the predictors and mediator, respectively. According to multivariable regression models after adjusting for potential covariates, serum FGF21 levels were significantly associated with brachial systolic blood pressure (β = 0.140), pulse pressure (β = 0.136), and aortic PWV (β = 0.144). Mediation analyses showed that serum FGF21 levels significantly mediated the relationship of eGFR with brachial systolic blood pressure (indirect effect [95% confidence interval]: -0.032 [-0.071, -0.002]), pulse pressure (-0.019 [-0.041, -0.001]), and aortic PWV (-0.457 [-1.053, -0.021]) and the relationship of UACR with aortic PWV (7.600 [0.011, 21.148]). These findings suggest that elevated circulating FGF21 levels partially mediate the association of elevated blood pressure and/or aortic stiffness with renal dysfunction in middle-aged and older adults.

Hemodynamic response and pulse wave analysis after upper- and lower-body resistance exercise with and without blood flow restriction

Resistance exercise (RE) has been shown to elevate hemodynamics and pulse wave reflection. However, the effects of acute RE with blood flow restriction (BFR) on hemodynamics and pulse wave reflection are unclear. The purpose of this study was to evaluate the differences between upper- and lower-body RE with and without BFR on hemodynamics and pulse wave reflection. Twenty-three young resistance-trained individuals volunteered for the study. Hemodynamics and pulse wave reflection were assessed at rest, 10, 25, 40, and 55 min after either upper- or lower-body with or without BFR. The upper-body RE (URE) consisted of the latissimus dorsi pulldown and chest press; the lower-body RE (LRE) consisted of knee extension and knee flexion. The BFR condition consisted of four sets of 30, 15, 15, and 15 repetitions at 30% 1-repetition maximum (1RM) while the without BFR condition consisted of four sets of 8 repetitions at 70% 1RM. Heart rate, rate pressure product, and subendocardial viability ratio significantly (p < 0.05) increased after all exercises. Brachial and aortic systolic blood pressure (BP) significantly (p < 0.05) elevated after LRE while brachial and aortic diastolic BP significantly (p < 0.05) reduced after URE. Augmentation pressure, augmentation index (AIx), AIx normalized at 75 bpm, and wasted left ventricular pressure energy significantly (p < 0.05) increased after URE while transit time of reflected wave significantly (p < 0.05) decreased after LRE. URE places greater stress on pulse wave reflection while LRE results in greater responses in BP. Regardless of URE or LRE, the cardiovascular responses between BFR and without BFR are similar.HIGHLIGHTS High-load resistance exercise and low-load resistance exercise with blood flow restriction may produce similar cardiovascular responses.Upper-body resistance exercise generates greater changes on pulse wave reflections while lower-body resistance exercise induces greater elevations in systolic blood pressure.

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.

Music attenuates a widened central pulse pressure caused by resistance exercise: A randomized, single-blinded, sham-controlled, crossover study

Increasing central blood pressure is an independent predictor of cardiovascular disease and is an acute effect of high-intensity resistance exercise. It has been shown that classical music suppresses increased peripheral pressure during exercise. We hypothesized that classical music would suppress increased central pressure induced by high-intensity resistance exercise. To confirm this hypothesis, we examined the effect of classical music on central pressure following high-intensity resistance exercise in 18 young men. A randomized, single-blinded, sham-controlled, crossover trial was conducted under parallel experimental conditions on four separate days. The order of experiments was randomized between sham control (seated rest), music (20-min classical music track compilation), resistance exercise (5 sets of 10 repetitions at 75% of 1 repetition maximum), and resistance exercise with music conditions. Aortic pressure was measured in all subjects. No significant interaction between time, music, and resistance exercise was observed for aortic systolic pressure and diastolic pressure. In contrast, aortic pulse pressure showed a significant interaction; that is, aortic pulse pressure significantly widened after resistance exercise, whereas music significantly attenuated this widening. No significant change was observed in aortic pulse pressure in sham control and music conditions. The present findings suggest that music attenuates resistance exercise-induced increase in central pressure.

Deterioration of sexual function is associated with central hemodynamics in adult Japanese men

Elevated aortic blood pressure is more strongly related to the onset of cardiovascular disease (CVD) than elevated brachial blood pressure. On the other hand, erectile dysfunction (ED) is a peripheral vascular disfunction and is also associated with CVD; however, the association between aortic blood pressure and ED has not yet been clarified. Therefore, we aimed to investigate the association between ED severity and aortic blood pressure in adult men. In 253 Japanese adult men (59 ± 16 years), aortic (estimated using a generalized transfer function) and peripheral hemodynamics were measured. Erectile function was assessed with a questionnaire (the International Index of Erectile Function 5: IIEF5), and participants were stratified into three groups based on the IIEF5 score (no ED, mild-to-moderate ED, and moderate-to-severe ED). Aortic systolic blood pressure (SBP) and pulse pressure (PP) were significantly higher in subjects with moderate-to-severe ED than in subjects with no ED or mild-to-moderate ED. In addition, the severity of ED was significantly associated with the time to reflection, augmentation pressure, and augmentation index. Multivariate linear regression analyses suggested that moderate-to-severe ED was significantly associated with aortic SBP and PP (β = 0.129; p = 0.047, β = 0.165; p = 0.013, respectively) but not brachial SBP or PP, after confounding factors were considered. These results suggest that moderate-to-severe ED is associated with elevated aortic blood pressure due to an earlier arrival of the reflected wave and is an independent predictor of elevated aortic blood pressure in Japanese men.

Aortic diastolic pressure decay modulates relation between worsened aortic stiffness and myocardial oxygen supply/demand balance after resistance exercise

High-intensity resistance exercise (RE) increases aortic stiffness and decreases the index of myocardial oxygen supply/demand balance (Buckberg index, BI); there is a correlation between the changes in these parameters. Central hemodynamics during diastole can explain the correlation. We aimed to investigate whether the aortic diastolic decay index mediates the association between changes in aortic stiffness and BI by high-intensity RE. We evaluated the effect of high-intensity RE on aortic stiffness, BI, aortic decay index, and their associations in 52 young men. Subjects were studied under parallel experimental conditions on two separate days. The order of experiments was randomized between RE (5 sets of 10 repetitions at 75% of 1-repetition maximum) and sham control (seated rest). Aortic pulse wave velocity (PWV; index of aortic stiffness), BI, and aortic decay index were measured in all subjects. Aortic decay index was quantified by fitting an exponential curve: P(t) = P₀e^-λt (where λ is decay index, P₀ is end-systolic pressure and t is time from end-systole). Aortic PWV and decay index increased and BI decreased after RE. RE conditions showed that change in the aortic decay index was associated with changes in aortic PWV and changes in aortic PWV were related to changes in BI, although the PWV-BI relationship was not significant after accounting for decay index change. Mediation analysis revealed the mediating effect of the aortic decay index on the relationship between changes in aortic PWV and BI. The present findings suggest that high-intensity RE-induced aortic stiffening worsens myocardial viability by accelerating aortic diastolic exponential decay.NEW & NOTEWORTHY Aortic pulse wave velocity (PWV) and diastolic decay index increased and Buckberg index (BI) decreased after resistance exercise (RE). Mediation analysis revealed a mediating effect of aortic decay index on the relationship between changes in aortic PWV and BI. The present study provides evidence that high-intensity RE-induced aortic stiffening accelerates aortic decay and aortic decay can account for the relationship between aortic stiffening and a deteriorated surrogate marker of myocardial oxygen supply/demand balance induced by high-intensity RE.