Exercise Blood Pressure Research Articles

Nitric Oxide and Decreases in Resistance Exercise Blood Pressure With Aerobic Exercise Training in Older Individuals.

An exaggerated blood pressure response to resistance exercise is a marker of masked hypertension and a risk factor for future essential hypertension. Habitual aerobic exercise decreases systolic blood pressure (SBP) during resistance exercise in older individuals, but the underlying mechanisms have not been explored. This study tested the hypothesis that nitric oxide (NO) mediates a reduction of resistance exercise SBP with aerobic training in older individuals. Normotensive older adults participated in a 6-week program as a part of the aerobic training group (n = 23, exercised for an average of 4.4 d/wk and 59 min/d) or the control group (n = 26, asked not to modify their lifestyle during the experimental period). The aerobic exercise intervention increased plasma concentrations of nitrite/nitrate (NOx, end products of NO) and decreased SBP during a one-hand arm curl exercise at 20% and 40% of one-repetition maximum and brachial-ankle pulse wave velocity (an index of arterial stiffness). In the control group, there were no differences in these measures before and after the experimental period. Changes in plasma NOx concentrations during the study period were correlated with changes in resistance exercise SBP. Stepwise regression revealed that changes in plasma NOx concentrations during the experimental period are a significant factor of changes in resistance exercise SBP, independent of age, sex, and changes in serum lipid profile, maximal oxygen uptake, resting SBP, and other variables. These results suggest that NO is associated with decreases in resistance exercise SBP with aerobic training in older individuals and help us better understand why habitual aerobic exercise prevents cardiovascular disease.

Using the immediate blood pressure benefits of exercise to improve exercise adherence among adults with hypertension: a randomized clinical trial.

A single exercise session evokes immediate blood pressure (BP) reductions that persist for at least 24 h, termed postexercise hypotension (PEH). Self-monitoring of PEH may foster positive outcome expectations of exercise, and thus, enhance exercise adherence among adults with hypertension. To compare the efficacy of self-monitoring of exercise (EXERCISE) versus exercise and PEH (EXERCISE + PEH) to improve exercise adherence and BP control among adults with hypertension. Adults with high BP were randomized to EXERCISE (n = 12) or EXERCISE + PEH (n = 12). Participants underwent supervised, moderate intensity aerobic exercise training for 40-50 min/session, 3 days/week for 12 weeks and encouraged to exercise unsupervised at home at least 30 min/day, 1-2 days/week. EXERCISE + PEH also self-monitored BP before and after exercise. Adherence was calculated as [(no. of exercise sessions performed/no. of possible exercise sessions) × 100%]. BP was measured pre and posttraining. Healthy, middle-aged (52.3 ± 10.8 years) men (n = 11) and women (n = 13) with hypertension (136.2 ± 10.7/85.2 ± 8.9 mmHg) completed exercise training with 87.9 ± 12.1% adherence. EXERCISE + PEH demonstrated greater adherence to supervised training (94.3 ± 6.6%) than EXERCISE (81.6 ± 13.2%; P = 0.007). EXERCISE + PEH performed 32.6 ± 22.5 min/week more unsupervised home exercise than EXERCISE (P = 0.004), resulting in greater exercise adherence (107.3 ± 18.7%) than EXERCISE (82.7 ± 12.2%; P = 0.002). Post versus pretraining BP was reduced -7.4 ± 11.3/-4.9 ± 9.9 mmHg (P < 0.025) with no statistical difference between EXERCISE (-5.2 ± 13.3/-3.6 ± 6.1 mmHg) and EXERCISE + PEH (-9.9 ± 11.3/-6.1 ± 6.9 mmHg; P > 0.344). The current study is the first to demonstrate that PEH self-monitoring is an efficacious tool to improve exercise adherence among a small sample of adults with hypertension. Future research among a larger, more diverse sample is needed to confirm these novel findings and determine whether EXERCISE + PEH translates to better BP control relative to EXERCISE self-monitoring alone.

Masked hypertension and submaximal exercise blood pressure among adolescents from the Avon Longitudinal Study of Parents and Children (ALSPAC).

Masked hypertension is associated with increased cardiovascular risk but is undetectable by clinic blood pressure (BP). Elevated systolic BP responses to submaximal exercise reveal the presence of masked hypertension in adults, but it is unknown whether this is the case during adolescence. We aimed to determine if exercise BP was raised in adolescents with masked hypertension, and its association with cardiovascular risk markers. A total of 657 adolescents (aged 17.7±0.3years; 41.9% male) from the Avon longitudinal study of parents and children (ALSPAC) completed a step-exercise test with pre-, post-, and recovery-exercise BP, clinic BP and 24-hour ambulatory BP. Masked hypertension was defined as clinic BP <140/90mmHg and 24-hour ambulatory BP ≥130/80mmHg. Assessment of left-ventricular (LV) mass index and carotid-femoral pulse wave velocity (aortic PWV) was also undertaken. Thresholds of clinic, pre-, post-, and recovery-exercise systolic BP were explored from ROC analysis to identify masked hypertension. Fifty participants (7.8%) were classified with masked hypertension. Clinic, pre-, post-, and recovery-exercise systolic BP were associated with masked hypertension (AUC≥0.69 for all, respectively), with the clinic systolic BP threshold of 115mmHg having high sensitivity and specificity and exercise BP thresholds of 126, 150, and 130mmHg, respectively, having high specificity and negative predictive value (individually or when combined) for ruling out the presence of masked hypertension. Additionally, this exercise systolic BP above the thresholds was associated with greater left-ventricular mass index and aortic PWV. Submaximal exercise systolic BP is associated with masked hypertension and adverse cardiovascular structure in adolescents. Exercise BP may be useful in addition to clinic BP for screening of high BP and cardiovascular risk in adolescents.

Exercise Capacity in Asymptomatic Adult Patients Treated for Coarctation of the Aorta

A reduced exercise capacity is a common finding in adult congenital heart disease and is associated with cardiovascular morbidity and mortality. However, data on exercise capacity in patients after repair of coarctation of the aorta (CoA) are scarce. Furthermore, a high rate of exercise-induced hypertension has been described in CoA patients. This study sought to assess exercise capacity and blood pressure response in asymptomatic patients long-term after CoA repair in relation to left ventricular and vascular function. Twenty-two CoA patients (age 30 ± 10.6 years) with successful surgical repair (n = 12) or balloon angioplasty (n = 10) between 3 months and 16 years of age with a follow-up of > 10 years underwent cardiopulmonary exercise testing at a mean follow-up of 23.9 years. Exercise capacity (peak oxygen uptake; VO2peak) and blood pressure response were compared to age- and gender-matched reference values. Left ventricular function and volumetric analysis was performed using cardiovascular magnetic resonance imaging. CoA patients showed preserved exercise capacity compared to the healthy reference group, with a VO2peak of 41.7 ± 12.0 ml/kg/min versus 44.9 ± 6.7 ml/kg/min. VO2peak/kg showed a significant association with age (p < 0.001) and male gender (p ≤ 0.001). Exercise-induced hypertension occurred in 82% of CoA patients, and was strongly related to left ventricular mass (p = 0.04). Of the 41% of patients who were normotensive at rest, 78% showed exercise-induced hypertension. No significant correlation was found between peak exercise blood pressure and age, BMI, age at time of repair, LVEF, or LV dimensions. Exercise capacity is well preserved in patients long-term after successful repair of coarctation of the aorta. Nevertheless, a high number of patients develop exercise hypertension, which is strongly related to systemic hypertension. Regular follow-up, including cardiopulmonary exercise testing, and aggressive treatment of hypertension after CoA repair is strongly advised.

Acute Soy Supplementation Improves 20-km Time Trial Performance, Power, and Speed.

Isoflavones, a chemical class of phytoestrogens found in soybeans and soy products, may have biological functions similar to estradiol. After binding with ERβ or perhaps independently of estrogen receptors, isoflavones may augment vascular endothelial relaxation, contributing to improved limb blood flow. To determine if acute fermented soy extract supplementation influences 20-km time trial cycling performance and cardiac hemodynamics compared with a placebo. Subjects included 25 cyclists and triathletes (31 ± 8 yr, V˙O2peak: 55.1 ± 8.4 mL·kg·min). Each subject completed a V˙O2peak assessment, familiarization, and two 20-km time trials in randomized order after ingestion of a fermented soy extract supplement or placebo. The fermented soy extract consisted of 30 g powdered supplement in 16 fl. ounces of water. The placebo contained the same quantities of organic cocoa powder and water. Each trial consisted of 60 min of rest, 30 min at 55% Wpeak, and a self-paced 20-km time trial. Soy supplementation elicited a faster time to 20-km completion (-0.22 ± 0.51 min; -13 s), lower average HR (-5 ± 7 bpm), and significantly greater power (7 ± 3 W) and speed (0.42 ± 0.16 km·h) during the last 5 km of the time trial compared with placebo. Analysis of the results by relative fitness level (<57 vs ≥ 57 mL⋅kg⋅min) indicated that those with a higher level of fitness reaped the largest performance improvement alongside a reduced HR (-5 ± 7 bpm). Ingestion of a fermented soy extract supplement improved sprint-distance performance through improvements in both power and speed. For those with great aerobic fitness, soy supplementation may help to decrease cardiac demand alongside performance improvement.

Moderate to Severe Obstructive Sleep Apnea in Military Personnel Is Not Associated With Decreased Exercise Capacity.

Studies of older and less active patients with obstructive sleep apnea (OSA) have reported decreased exercise capacity as measured by peak oxygen uptake (VO2 max) during cardiopulmonary exercise testing (CPET). We looked to determine whether VO2 max was decreased in younger patients with OSA who regularly exercise as would be encountered in the military. We evaluated military personnel who had undergone pulmonary function testing (PFT), CPET, and polysomnography (PSG) as part of the larger STAMPEDE III study for comprehensive evaluation of exertional dyspnea. For analysis, patients were classified into two groups, the OSA group with an apnea-hypopnea index (AHI) ≥ 15 events/h and a control group with an AHI < 15 events/h. Mean AHI was 32.7 in the OSA group (n = 40) versus 5.8 in the control group (n = 58) with no significant difference in age (40.7 years versus 39.4 years) or body mass index (30.4 kg/m2 versus 29.9 kg/m2). PFT was normal in both groups including diffusing capacity (100.7% versus 96.5%) and FEV1 (89.2% versus 86.2%). VO2 max was not significantly different in the OSA group compared to the control group (101.3% versus 102.8%; P = .60) with both groups having normal exercise capacity. Exercise blood pressure response was normal and peak heart rate trended toward a blunted response in the OSA group (166.0 bpm versus 171.6 bpm, P = .09). Younger military personnel with moderate to severe OSA do not have decreased exercise capacity. The effect of OSA on exercise tolerance may be influenced by additional factors and is likely too small to be noted in this population. A commentary on this article appears in this issue on page 819.

Characterization Of Exercise Blood Pressure Responses In Adolescents With A Chronic Inflammatory Condition

Exaggerated blood pressure (BP) responses to exercise are prognostic of cardiovascular disease (CVD) in adults. There are no criteria to define exaggerated BP responses in children, yet higher exercise BPs have been shown to be associated with CVD risk factors. Therefore, exercise BPs may provide important prognostic information in children, especially those at higher risk for CVD. PURPOSE: The study sought to characterize the exercise BP responses in an “at-risk” sample of adolescents with a chronic inflammatory condition. METHODS: Twenty-one adolescents (7 males; 14.7 ± 1.8 years) with a confirmed single diagnosis of chronic kidney disease, cystic fibrosis, inflammatory bowel disease, juvenile idiopathic arthritis or type 1 diabetes mellitus participated in this study. Brachial BP was assessed using a motion-tolerant automated auscultatory device every 2 minutes during the McMaster All-Out Progressive Continuous cycling test, using pediatric-specific criteria for test termination at “maximal” effort. Maximal BPs were compared to (1) sex-specific reference values for healthy adolescents, and (2) exaggerated BP criteria for adults. RESULTS: Maximal systolic BPs for males and females were 184 ± 35 and 172 ± 19 mmHg, respectively. Maximal diastolic BPs for males and females were 71 ± 11 and 74 ± 9 mmHg, respectively. Two males (29%) had a maximal BP above reference values with one having a higher systolic BP and the other having a higher diastolic BP. Nine females (64%) had a maximal BP above reference values with five exceeding the systolic BP reference, one exceeding the diastolic BP reference, and three exceeding both BP references. An exaggerated BP response occurred in two males and two females. CONCLUSION: Approximately half of our sample of adolescents with a chronic inflammatory condition reached higher exercise BPs compared to healthy adolescent reference values. Elevated exercise BPs were also more common in females compared to males, and 19% of our sample met the adult-criteria for exaggerated BP responses. Collectively our observations of elevated exercise BPs in an “at-risk” population highlight the importance of examining BP responses in children, including research on its potential prognostic value. Funding: Canadian Institutes of Health; Heart and Stroke Foundation

Systolic Blood Pressure Responses in Relation to Cardiorespiratory Fitness of Young Adults

ABSTRACT Background: We aimed to assess systolic blood pressure (SBP) responses in relation to the cardiorespiratory fitness (CRF) levels of apparently healthy, young Nigerian adults during and after a submaximal-effort exercise test. Methods: One hundred and twelve young adults (62 males and 50 females) participated in the study and were grouped according to their CRF levels—low, moderate, and high. The participants performed submaximal ergometer exercise tests to elicit exercise and postexercise blood pressure responses. Results: Males and females with high CRF indicated significantly (P &amp;lt; 0.05) higher change of exercise SBP at peak exercise (ΔEx·SBPpeak), and post-SBP decline compared with the other CRF groups. In addition, higher (P &amp;lt; 0.05) ΔEx·SBP2min and faster SBP recovery time were observed in the high CRF group compared to low CRF group. Females with high CRF had a significantly (P &amp;lt; 0.05) higher peak oxygen pulse and energy expenditure compared with the lower CRF groups. There was a very low incidence of abnormal SBP responses among the study population. Conclusion: Greater exercise SBP responses, an indication of higher cardiac output due to greater metabolic demand, and faster SBP recovery were observed in participants with a high CRF compared with the other CRF groups. These findings suggest that regular exercise which maintains a higher CRF in young Nigerian adults may be related to a healthy SBP exercise response.

Maximal Exercise Blood Pressure and Glycemic Responses: Association with Resting Parameters in Healthy Young Adults.

Hypertension and hyperglycemia are known components of the metabolic syndrome. Massive adrenergic stimulation during high-intensity exercise has been associated to high blood pressure (BP) and blood glucose concentration. The predictive value of exercise-induced hypertension is an area of active research. An exaggerated and persistent hyperglycemia induced by intense exercise has been described in type-1 diabetics. For healthy subjects is not clear if BP and glycemic responses during maximal exercise are correlated with resting BP and glycemic values within the span of normal range. PURPOSE: To find the association between resting and maximal exercise BP and glycemic responses in healthy young adults. METHODS: An exploratory analysis was conducted on 145 young adults (63 female) aged 18-25 deemed healthy by medical and anthropometric evaluation (body mass index 18.4 - 24.9) as well as laboratory tests, including a complete metabolic profile. All subject had normal resting BP, glycated hemoglobin A1c (HbA1c) and fasting glucose concentration (FG) values. On a separate day subjects performed a maximal ramp cardiopulmonary exercise test (CPET) on a cycle ergometer; capillary blood glucose concentration (cBG) and BP were measured every 2.5 minutes. Pearson product-moment correlations between resting and exercise parameters were assessed with a significance level <0.05. Separate analysis were made for males and females. RESULTS: The analysis for the female group is presented: at maximal workload, cBG was correlated with HbA1c (r=0.29, p= 0.016) while diastolic BP was correlated with resting diastolic BP (r=0.26, p=0.034). Overall, maximal cBG was correlated with HbA1C (r= 0.27, p= 0.025) and FG (r=0.27, p=0.026) and maximal systolic BP was correlated with resting systolic BP (r=0.27, p=0.0009). CONCLUSIONS: For healthy young females BP and glycemic parameters at rest were positively associated with cBG and BP responses at or near maximal workloads during CPET. In otherwise healthy adults with resting BP and BG values in the upper limit of normal, acute intense exercise could play a role unmasking early subclinical cBG and BP changes in the metabolic syndrome continuum. The predictive and prognostic role of these findings remains to be determined. Supported by COLCIENCIAS Grant number 120356934972, 713-2013.

Left ventricular hypertrophy in middle-aged endurance athletes: is it blood pressure related?

Both regular physical activity and hypertension may be related to increased myocardial thickness, but the interplay between these two factors in causing cardiac remodeling in athletes is still a matter of debate. The aim of this study was to analyze the relation between resting and peak exercise blood pressure (BP) and myocardial hypertrophy in healthy middle-aged amateur endurance athletes. The study included 30 male, long-term athletes (mean age 40.9±6.6 years) who underwent resting BP assessment, cardiopulmonary exercise testing with peak exercise BP measurement, and cardiac magnetic resonance. We found that interventricular septal diameter is increased in athletes with high-normal resting BP (n=11, 37%) - median 13 mm (interquartile range: 12-13.75 mm), but not in those with optimal or normal BP (n=19) - median 10 mm (10-11.75 mm), P=0.001. This finding is accompanied by significantly higher left and right ventricular mass index and larger left atrial area in the first group. These differences are even more pronounced in athletes in whom high-normal BP is accompanied by exaggerated blood pressure response (EBPR) to exercise, whereas isolated EBPR to exercise does not lead to hypertrophy or further left atrial enlargement. Prehypertension, isolated or combined with EBPR to exercise, affects cardiac remodeling in athletes. Identification of increased myocardial thickness in pure endurance middle-aged athletes should merit further investigation on masked hypertension.

The effects of slow loaded breathing training on exercise blood pressure in isolated systolic hypertension.

Slow loaded breathing training has been shown to reduce resting blood pressure (BP) in isolated systolic hypertension (ISH), but it is not known whether this also reduces their exaggerated BP responses to exercise. The study was a randomized controlled trial with block allocation stratified by sex. Twenty ISH patients (68±5yrs, 11 males) were randomized with one group undertaking 8-weeks training with slow loaded breathing (SLB: 25% maximum inspiratory pressure, 6 breaths per minute, 60 breaths every day) or deep breathing control (CON), with 8weeks follow-up. Outcome measures were home BP and heart rate (HR) with laboratory measures of BP and HR responses to static handgrip and dynamic arm cranking exercise. Data were compared with a two-week run-in baseline. Home systolic BP fell by 22mmHg (20-23; mean, 95% CI), diastolic BP by 9mmHg (7-11), and HR by 12bpm (9-15; all p<.001) as a result of SLB training. Systolic BP at the end of 2-min isometric handgrip was 189±10mmHg (mean, SD) before training and 157±6mmHg following SLB training. After 4-min arm exercise, systolic BP, measured at the ankle, was reduced from 243±8mmHg during the run-in period to 170±15mmHg after SLB training with no change for CON. The reduction in exercise BP, in both types of exercise, was partly due to a reduction in resting BP and to a smaller increase above resting. Systolic and pulse pressures remained below run-in values 8weeks after the end of SLB training, and BP response to handgrip exercise remained below run-in values at 4weeks after SLB training. SLB not only reduces resting BP in ISH but also the responses to both static and dynamic exercise, potentially reducing the negative aspect of exercise for cardiovascular health.

Metabolic acidosis augments exercise pressor responses in chronic kidney disease.

Chronic kidney disease (CKD) patients experience augmented blood pressure (BP) reactivity during exercise that is associated with an increased risk of cardiovascular mortality. Exaggerated exercise pressor responses in CKD are in part mediated by augmented sympathetic nerve activation due to heightened muscle mechanoreflex. One mechanism that may lead to sensitization of the muscle mechanoreflex in CKD is metabolic acidosis. We hypothesized that CKD patients with low serum [bicarbonate] would exhibit exaggerated increases in arterial BP, greater reductions in muscle interstitial pH, and fatigue earlier during exercise compared with CKD patients with normal serum bicarbonate concentration ([bicarbonate]). Eighteen CKD participants with normal serum [bicarbonate] (≥24 mmol/l, normal-bicarb) and 9 CKD participants with mild metabolic acidosis ([bicarbonate] range 20-22 mmol/l, low-bicarb) performed rhythmic handgrip (RHG) exercise to volitional fatigue at 40% of maximal voluntary contraction. BP, heart rate, and muscle interstitial pH using near infrared spectroscopy were measured continuously. While mean arterial pressure (MAP) increased with exercise in both groups (P ≤ 0.002), CKD with low-bicarb had an exaggerated MAP response compared with CKD with normal-bicarb (+5.9 ± 1.3 mmHg/30 s vs. +2.6 ± 0.5 mmHg/30 s, P = 0.01). The low-bicarb group reached exhaustion earlier than the normal-bicarb group (179 ± 21 vs. 279 ± 19 s, P = 0.003). There were no differences in the change in muscle interstitial pH during exercise between groups (P = 0.31). CKD patients with metabolic acidosis have augmented exercise-induced increases in BP and poorer exercise tolerance. There was no difference in change in muscle interstitial pH between groups, however, suggesting that augmented exercise BP responses in metabolic acidosis are not due to impaired muscle-buffering capacity.

Deteriorated Cardiometabolic Risk Profile in Individuals With Excessive Blood Pressure Response to Submaximal Exercise.

Early identification of individuals at increased cardiometabolic risk is an essential step to improve primary preventive interventions. Excessive maximal exercise blood pressure (EBP) has been associated with several adverse outcomes. We examined how submaximal EBP could help us to identify individuals with a deteriorated cardiometabolic risk profile. Data from an observational study of 3,913 participants from a convenience sample were used. Subjects included in the analyses completed a comprehensive cardiometabolic health assessment (resting blood pressure [BP]; waist circumference; lipid profile; HbA1c; submaximal treadmill exercise test including a standardized stage [3.5 mph and 2% slope] with BP and heart rate measurements). Participants were classified on BP response at the standardized stage (Normal or Excessive Response). Excessive response was defined as systolic BP ≥ 80th percentile or diastolic BP ≥ 90 mmHg. Subjects were also classified into five resting BP subgroups according to current guidelines. The Excessive Response group had more deteriorated cardiometabolic and cardiorespiratory profiles than the Normal Response group (P ≤ 0.01). The Excessive Response group also showed a greater proportion of carriers of the hypertriglyceridemic waist phenotype in most resting BP subgroups (P ≤ 0.05). Finally, excessive BP response to submaximal exercise showed an independent contribution on cardiometabolic and cardiorespiratory factors beyond age, sex, and resting BP. This study demonstrates that an excessive BP response to a submaximal exercise is associated with a deteriorated cardiometabolic risk profile beyond resting BP profile. Therefore, submaximal EBP represents a simple screening tool to better identify at-risk individuals requiring aggressive preventive lifestyle interventions.

Effects of L-arginine Supplementation and Aerobic Training on Hemodynamic Indices of Obese Men

BackgroundL-arginine is a precursor to nitric oxide, which can affect some hemodynamic indices.ObjectivesThe purpose of this study was to investigate the effect of one-month aerobic training with and without supplementation of L-arginine on hemodynamic indices in obese men.MethodsA quasi-experimental double-blind, study was carried out. Subjects (age, 30 - 45 years; BMI, 38 - 40 kg.m-2) were randomly assigned to an exercise and L-arginine supplementation group (n = 10) and placebo group (n = 10). Before and after four weeks of aerobic exercise (three 90 - 120 min sessions per week at 65% - 85% of maximal heart rate), systolic and diastolic blood pressure, and rate pressure product (RPP) were measured at rest. The analysis of variance was used to determine the interaction between the two factors of exercise and supplementation of L-arginine on the dependent variables at P < 0.05.ResultsFour weeks of aerobic exercise reduced the RPP in both groups (P ≤ 0.05), while the L-arginine group significantly reduced systolic blood pressure (116.6 ± 3.40), diastolic blood pressure (76 ± 2.29) and RPP (8918.2 ± 722.86).ConclusionsL-arginine supplementation along with four weeks of aerobic exercise can be effective in controlling hypertensive of obese men.

Multimodal exercise ameliorates exercise responses and body composition in head and neck cancer patients receiving chemotherapy.

Studies have found that many chemotherapy drugs will produce multiple side effects and complications in cancer patients, especially in the case of the cardiovascular disease. This study was intended to investigate whether the exercise training intervention could improve the body composition and exercise responses of patients with head and neck (H&N) cancer who are receiving chemotherapy. This is a randomized controlled trial. Eighty-four H&N patients were assigned to sedentary group or exercise group. The data were collected pretraining and posttraining, where the body composition, heart rate (HR), blood pressure (BP), rate-pressure product (RPP), and exercise capacity were measured. Our data reported that body weight and body mass index were decreased after 8weeks of chemotherapy in the sedentary group but not in the exercise group. The decreased visceral fat and the increased skeletal muscle rate had been found in the exercise group after 8weeks of training. In addition, in the exercise group, the HR, HR recovery, BP, BP recovery, RPP, and minutes walking distance were better than the sedentary group. Results from this study suggested exercise training significantly improved exercise responses and body composition. These findings suggested that exercise can help to promote cardiopulmonary fitness and exercise capacity for H&N cancer patients undergoing chemotherapy.

Animal Modeling for Hologenome: New inbred and conplastic rat exercise models for uncovering crosstalk between nuclear DNA, mitochondrial DNA, and gut microbiota

IntroductionThe hologenome is an ensemble of nuclear DNA (nDNA), mitochondrial DNA (mtDNA), and the microbiome that forms a unit of genetic selection that can propagate from one generation to the next. There is increasing evidence for inherited mitochondria‐gut microbiota involvement in cardiovascular and metabolic diseases. Here, we expand on the selectively‐bred Low Capacity Runner/High Capacity Runner (LCR/HCR) rat exercise model system into a genetically defined rat model framework for studying holobionts in controlled laboratory settings.MethodsAt Generation 23 of selection, we identified extreme representatives of female and male LCR and HCR rats and conducted a series of brother‐sister mating to produce inbred strains‐ LCR/Tol and HCR/Tol. We also developed two conplastic strains, one with nDNA from HCR and mtDNA from LCR, and the other with nDNA from LCR and mtDNA from HCR ‐LCR.HCRmt/Tol and HCR.LCRmt/Tol. mtDNA from LCR/Tol and HCR/Tol strains were compared with publicly available mtDNA from common inbred strains. Rats were phenotyped for cardiovascular risks, which included treadmill exercise capacity, VO2max, echocardiography, and blood pressure (BP) telemetry. Fecal microbial communities were profiled using 16S rRNA sequencing and metatranscriptomics.ResultsAs expected, HCR/Tol had significantly higher exercise capacity compared to LCR/Tol but little effect by mismatched mtDNA suggesting that the nDNA is dominant for regulating aerobic exercise capacity. VO2max measurement confirmed high exercise capacity in HCR/Tol and low in LCR/Tol. LCR mtDNA was identical to mtDNA from Wistar Kyoto inbred strain, while HCR mtDNA was identical to mtDNA from Fischer 344 × Brown Norway F1‐hybrid strain. Consistent with reports from selected LCR HCR rats, LCR/Tol showed significantly increased mean arterial pressure (MAP), systolic BP (SBP), and diastolic BP (DBP) compared to the HCR/Tol. Transfer of mtDNA from HCR to LCR nDNA background decreased MAP, SBP, DBP, and preserved diastolic cardiac function. In contrast, there was no difference in BP or cardiac parameters between HCR/Tol and HCR.LCRmt/Tol. Microbiome analysis indicated that host genomes co‐inhabit with differential commensal microbiota. Metatranscriptomics showed HCR/Tol had enhanced function in carbohydrate and amino acid metabolism, microbial metabolites production, and stress management.ConclusionWe successfully generated and systematically characterized genotypes and phenotypes of inbred and conplastic LCR/Tol and HCR/Tol animal models for holobiont studies. The inbred and conplastic strains retained key features of LCR HCR selectively bred models ‐‐ some influenced by nDNA‐mtDNA interaction. These models provide for a new pre‐clinical method to explore gut microbiota as therapeutic targets for complex diseases such as hypertension.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

The Effect of Age on Exercise Blood Pressure Responses Following Short‐term Water Deprivation

Aging impairs regulation of body fluid homeostasis (attenuated thirst sensations, blunted anti‐diuretic hormone release, and reduced renal function) leading to a greater incidence of hypernatremia (elevated serum sodium concentrations ([sNa+])). Previous studies suggest significantly greater increases in [sNa+] following water deprivation (WD) in older adults (OA) compared to young adults (YA). This is problematic as data from animal models suggest a relation between plasma hypernatremia and exaggerated blood pressure (BP) responses during sympathoexcitatory stimuli. This is clinically relevant in humans because exaggerated BP responses to sympathoexcitatory stimuli is associated with greater future incidence of hypertension. However, it is unknown whether WD causes greater increases in [sNa+] and consequently larger increases in BP responses during sympathoexcitatory stimuli in OA compared to YA.PURPOSETo test the hypothesis that WD causes greater increases in [sNa+] and consequently larger increases in BP responses during exercise pressor reflex activation in OA compared to YA.METHODSTwenty‐five healthy YA (11F/14M; age: 25±1 yrs; BMI: 23±1 kg/m2; screening BP: 108±2/59±2 mmHg) and eight healthy OA (7F/1M; age: 67±2 yrs; BMI: 23±1 kg/m2; screening BP: 119±5/77±3 mmHg) completed two hydration conditions in random crossover fashion. A normal hydration control visit (CON; 23mL water/kg bodyweight/day for three days) and WD visit (stepwise reduction in water intake over three days followed by a 16h WD prior to testing) were separated by at least one week. Beat‐to‐beat BP was measured via finger photoplethysmography throughout a ten‐minute baseline, isometric handgrip exercise (HG; 30% MVC, two minutes), and post‐exercise ischemia (PEI; upper arm occlusion, three minutes). Changes in [sNa+] and resting BP were analyzed using two‐way independent group ANOVAs (condition x age). Responses during the final minute of HG and all three minutes of PEI were each compared to the baseline period using a two‐way ANCOVA (condition x age, with resting brachial systolic BP as a covariate). Significance was set a priori at p&lt;0.05.RESULTSBoth age groups had higher [sNa+] during WD compared to CON (YA: 141.3±0.5 vs. 142.6±0.5, OA: 142.2±1.0 vs. 143.1±0.8 mmol/L, condition: p=0.024, age: p=0.421, interaction: p=0.601). OA had higher resting BP than YA during both conditions (YA: 112±2 vs. 112±2, OA: 144±8 vs. 139±7 mmHg, condition: p=0.220, age: p&lt;0.001, interaction: p=0.076). Systolic BP responses were not different between age groups or conditions during HG (YA: Δ15±2 vs. 17±2, OA: Δ18±7 vs. 16±2 mmHg, F(1,61)=0.539, p=0.708, partial η2=0.04), or PEI (YA: Δ14±2 vs. 17±3, OA: Δ23±6 vs. 20±2 mmHg, F(1,61)=0.331, p=0.567, partial η2=0.005; CON vs. WD mean±SEM for all results).CONCLUSIONThese preliminary data suggest that short‐term WD does not elicit larger increases in [sNa+] or larger increases in BP responses during exercise pressor reflex activation in OA compared to YA.Support or Funding InformationNIH Grant 1R01HL128388 (WBF &amp; SDS), NIGMS P20GM113125, and University Doctoral Fellowship (JCW).This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Dietary Salt Intake Exaggerates Arterial Blood Pressure during Exercise in healthy Normotensive Adults

High dietary salt intake is associated with an increased risk for the development of hypertension, cardiovascular (CVD) and cerebrovascular disease. Additionally, exaggerated blood pressure during dynamic exercise is independently predictive of future CVD beyond resting blood pressure and other conventional risk factors. This is critical given that in animal models, dietary salt negatively augments blood pressure responses during static hind‐limb contractions, suggesting an increased risk of an adverse CVD event during exercise with high dietary salt. However, it currently remains unknown if high salt intake increases arterial blood pressure and impairs vascular function during voluntary dynamic exercise in healthy men and women. Based on previous preclinical reports, we hypothesized that high salt intake would decrease resting vascular endothelial function, increase arterial blood pressure during dynamic exercise and decrease functional sympatholysis. Thirteen healthy men and women underwent a randomized, double‐blind, placebo‐controlled trial for 7 days with either 15g/day sodium chloride supplement or cellulose. Beat‐by‐beat mean (MAP), systolic (SBP) and diastolic (DBP) were recorded throughout the trial on the non‐exercising limb. Forearm blood flow (FBF) was calculated via mean blood velocity derived from ultrasonography on the brachial artery of the exercising limb. All patients performed a flow‐mediated dilation (FMD) protocol followed by (20% maximal voluntary contraction) submaximal hand‐grip exercise for 7 min with lower‐body negative pressure initiated during min 5 – 7. FMD was significantly reduced during the HS condition (HS: 2.2±0.26e−5; Pl: 4.1±0.56e−5; p&lt;0.01). Compared to placebo, the absolute steady‐state exercise MAP and SBP were significantly higher during HS compared to the placebo condition (p&lt;0.05). However, functional sympatholysis was not different between conditions (p=0.07). In summary, the results of this study show the effects of HS intake on arterial blood pressure during handgrip exercise. These findings highlight that the augmented exercise blood pressures may be key mediator for the increased risk for adverse CVD outcomes associated with high dietary salt intake.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Recovery of rate-pressure product and cardiac mortality in coronary artery disease patients with type 2 diabetes

AimsTo investigate prognostic significance of post-exercise recovery of rate-pressure product (RPP) in patients with stable coronary artery disease (CAD) and type 2 diabetes (T2D). MethodsPatients with angiographically documented CAD and T2D (n = 697) underwent symptom-limited bicycle exercise test. Exercise capacity (EC), heart rate, blood pressure and RPP responses to peak exercise and recovery (2′ and 5′ after cessation of exercise) were analyzed. Cardiac death was the primary and sudden cardiac death (SCD) secondary endpoint. ResultsDuring a median follow-up of 76 months, 49 cardiac deaths (7.0%) and 28 SCDs (4.0%) were observed. The recovery of RPP at 5′ was the strongest univariate predictor of cardiac death (hazard ratio [HR]: 2.55 per SD decrease, 95%CI: 1.82–3.58, p < 0.001) and SCD (HR: 2.34, 95%CI: 1.51–3.62, p < 0.001). In multivariate analysis, it remained significantly associated to cardiac death and SCD without (HR: 1.66, 95%CI: 1.14–2.41, p < 0.01 and HR: 1.75, 95%CI: 1.08–2.85, p < 0.05, respectively) and with additional adjustment for EC and peak RPP (HR: 1.45, 95%CI: 1.09–1.92, p < 0.05 and HR: 1.52, 95%CI: 1.01–2.27, p < 0.05, respectively). ConclusionsThe recovery of RPP after exercise is a potent predictor of cardiac death in patients with CAD and T2D. It provides significant prognostic information beyond EC and peak RPP.

Effects of L-arginine Supplementation and Aerobic Training on Hemodynamic Indices of Obese Men

Background: L-arginine is a precursor to nitric oxide, which can affect some hemodynamic indices. Objectives: The purpose of this study was to investigate the effect of one-month aerobic training with and without supplementation of L-arginine on hemodynamic indices in obese men. Methods: A quasi-experimental double-blind, study was carried out. Subjects (age, 30 - 45 years; BMI, 38 - 40 kg.m-2) were randomly assigned to an exercise and L-arginine supplementation group (n = 10) and placebo group (n = 10). Before and after four weeks of aerobic exercise (three 90 - 120 min sessions per week at 65% - 85% of maximal heart rate), systolic and diastolic blood pressure, and rate pressure product (RPP) were measured at rest. The analysis of variance was used to determine the interaction between the two factors of exercise and supplementation of L-arginine on the dependent variables at P &lt; 0.05. Results: Four weeks of aerobic exercise reduced the RPP in both groups (P ≤ 0.05), while the L-arginine group significantly reduced systolic blood pressure (116.6 ± 3.40), diastolic blood pressure (76 ± 2.29) and RPP (8918.2 ± 722.86). Conclusions: L-arginine supplementation along with four weeks of aerobic exercise can be effective in controlling hypertensive of obese men.