Acute moderate-intensity exercise induces vasodilation through an increase in nitric oxide bioavailiability in humans

Molecular insights of exercise therapy in disease prevention and treatment

Despite substantial evidence emphasizing the pleiotropic benefits of exercise for the prevention and treatment of various diseases, the underlying biological mechanisms have not been fully elucidated. Several exercise benefits have been attributed to signaling molecules that are released in response to exercise by different tissues such as skeletal muscle, cardiac muscle, adipose, and liver tissue. These signaling molecules, which are collectively termed exerkines, form a heterogenous group of bioactive substances, mediating inter-organ crosstalk as well as structural and functional tissue adaption. Numerous scientific endeavors have focused on identifying and characterizing new biological mediators with such properties. Additionally, some investigations have focused on the molecular targets of exerkines and the cellular signaling cascades that trigger adaption processes. A detailed understanding of the tissue-specific downstream effects of exerkines is crucial to harness the health-related benefits mediated by exercise and improve targeted exercise programs in health and disease. Herein, we review the current in vivo evidence on exerkine-induced signal transduction across multiple target tissues and highlight the preventive and therapeutic value of exerkine signaling in various diseases. By emphasizing different aspects of exerkine research, we provide a comprehensive overview of (i) the molecular underpinnings of exerkine secretion, (ii) the receptor-dependent and receptor-independent signaling cascades mediating tissue adaption, and (iii) the clinical implications of these mechanisms in disease prevention and treatment.

Understanding the mechanisms of disease modifying effects of aerobic exercise in people with Alzheimer's disease

Alzheimer's disease (AD) is a very disabling disease. Pathologically, it is characterized by the presence of amyloid plaques and neurofibrillary tangles in the brain that results in neurodegeneration. Its clinical manifestations include progressive memory impairment, language decline and difficulty in carrying out activities of daily living (ADL). The disease is managed using interventions such as pharmacological interventions and aerobic exercise. Use of aerobic exercise has shown some promises in reducing the risk of developing AD, and improving cognitive function and the ability to carry out both basic and instrumental ADL. Although, the mechanisms through which aerobic exercise improves AD are poorly understood, improvement in vascular function, brain glucose metabolism and cardiorespiratory fitness, increase in antioxidant capacity and haemoglobin level, amelioration of immune-related and inflammatory responses, modulation of concentration of circulating Neurotrophins and peptides and decrease in concentration of tau protein and cortisol level among others seem to be the possible mechanisms. Therefore, understanding these mechanisms is important to help characterize the dose and the nature of the aerobic exercise to be given. In addition, they may also help in finding ways to optimize other interventions such as the pharmacological interventions. However, more quality studies are needed to verify the mechanisms.

Exploring the Connection between Migraines and Pregnancy: The Impact of Physical Activity on Symptom Management

Migraine is a prevalent neurological disorder that significantly impacts the quality of life for affected individuals. The pathogenesis behind migraines is not yet fully understood, but hormonal changes, especially fluctuations in, estrogen and progesterone levels, have a significant role in the susceptibility of women to migraines. Pregnancy introduces a unique set of challenges for women who experience migraines, as they must navigate the complexities of managing their condition while safeguarding the health of both them and their unborn child. Pharmacological options for treating migraines during pregnancy are limited, and, therefore, there is a growing interest in exploring alternative approaches to migraine symptom relief and management. Physical activity during pregnancy provides a range of benefits, and it has gained attention as a potentially valuable tool for alleviating migraine symptoms in pregnant patients. This review explores the intricate relationship between migraines and pregnancy, emphasizing how physical activity and other alternative approaches may influence the frequency, severity, and overall experience of migraines during pregnancy. Through collaboration with healthcare providers and the adoption of personalized management strategies, women can strike a balance that supports both their own well-being and the healthy development of their unborn child. By examining existing research and emerging insights, we aim to provide a comprehensive understanding of the potential benefits and considerations of incorporating physical activity and other treatment options into migraine management strategies for pregnant women. Further research is needed to elucidate the specific mechanisms linking migraines, pregnancy, and physical activity, enabling the development of more targeted interventions and guidelines.

Rapid weight change as a predictor of disability among community-dwelling Japanese older adults

AIM

To fill the knowledge gap regarding weight change and the onset of disability in community-dwelling Japanese older adults, we investigated the potential effects of rapid weight change on disability risk as defined by Japan's long-term care insurance (LTCI) system.

METHODS

We analyzed data from a longitudinal study of 10 375 community-dwelling older Japanese adults (≥65 years) who were not LTCI needs certified at baseline and joined the study from 2002 to 2005. Weight change (percentage) was calculated by subtracting participants' weight in the previous year from that measured during a physical examination at study commencement. The five weight-change categories ranged from sizable weight loss (≤ -8.0%) to sizable weight gain (≥ +8.0%). Disability was defined according to LTCI certifications at follow-up. Hazard ratios (HRs) and 95% confidence intervals were calculated for new-onset disability using a Cox proportional hazards model that fitted the proportional subdistribution hazards regression model with weights for competing risks of death.

RESULTS

During the mean 10.5-year follow-up, 2994 participants developed a disability. Sizable weight loss (HR [95% confidence intervals], 1.41 [1.17-1.71]) and weight loss (1.20 [1.05-1.36]) were significant predictors of disability onset. Sizable weight gain (1.45 [1.07-1.97]) corresponded to severe disability. Stratified analyses by lifestyle and initial body mass index categories revealed more pronounced associations between weight change and disability risk in the unhealthy lifestyle and below initial normal body mass index groups.

CONCLUSIONS

Rapid and sizable weight gain could be additional criteria for disability risk in older adults. Geriatr Gerontol Int 2023; 23: 809-816.

Exercise-induced atrial fibrillation: A case report

Key Clinical Message

Middle-aged male athletes, with or without underlying coronary artery disease, exhibiting exercise induced blood pressure (BP) variability and diabetes can have an increased risk of developing atrial fibrillation (AF). Assessment in athletes should include long-term arrhythmia monitoring. In addition, it is important to exert patients beyond their calculated target heart rate (HR) during an exercise stress test to detect exercise-induced AF. We suggest this strategy be specifically used for athletes with complaints of intermittent palpitation and chest pain. Referral to an electrophysiologist for a possible ablation procedure should be considered for the management of AF in athletes in whom the use of beta-blockers may limit exercise tolerance. Bleeding risk with the use of oral anticoagulation needs to be adequately evaluated in athletes with AF who engage in high-intensity exercise or activities.

Abstract

The report highlights the case of a 54-year-old Caucasian male (height 5.11', BMI 29.8) who presented with complaints of chest pain, mild coronary artery disease, palpitation, dizziness, and labile BP with high-intensity biking exercise. Diagnostic tests (exercise stress test, cardiac catheterization, Holter monitor, and Bardy patch) using standard procedure were unsuccessful at detecting the problem. In a repeat exercise stress test, the patient was exerted beyond the calculated HRmax (up to 117%) when the patient's heart rhythm flipped from sinus rhythm to AF. The patient was referred to a cardiac electrophysiologist and an ablation procedure was performed to prevent exercise-induced AF with high-intensity exercise. Young adults, with or without early coronary artery disease, performing high-intensity endurance exercises may be at risk of developing exercise-induced AF. This phenomenon is prevalent and well documented in the skiing population and patients with variance in BP during exercise. Endurance athletes tend to have a lower resting HR. As such, the use of standard rate-control medications in patients with exercise-induced AF may not be appropriate. Referral to a cardiac electrophysiologist and ablation procedures should be considered in this population for management and symptom control. If tolerated, especially in young adults with complaints of palpitation and chest pain, patients should be exerted beyond their calculated HRmax during an exercise stress test to diagnose an underlying condition of exercise-induced AF.

Aerobic capacity and [Formula: see text] kinetics adaptive responses to short-term high-intensity interval training and detraining in untrained females

PURPOSE

This study investigated the physical fitness and oxygen uptake kinetics (τ[Formula: see text]) along with the O2 delivery and utilization (heart rate kinetics, τHR; deoxyhemoglobin/[Formula: see text] ratio, ∆[HHb]/[Formula: see text]) adaptations of untrained female participants responding to 4 weeks of high-intensity interval training (HIIT) and 2 weeks of detraining.

METHODS

Participants were randomly assigned to HIIT (n = 11, 4 × 4 protocol) or nonexercising control (n = 9) groups. Exercising group engaged 4 weeks of treadmill HIIT followed by 2 weeks of detraining while maintaining daily activity level. Ramp-incremental (RI) tests and step-transitions to moderate-intensity exercise were performed. Aerobic capacity and performance (maximal oxygen uptake, [Formula: see text]; gas-exchange threshold, GET; power output, PO), body composition (skeletal muscle mass, SMM; body fat percentage, BF%), muscle oxygenation status (∆[HHb]), [Formula: see text], and HR kinetics were assessed.

RESULTS

HIIT elicited improvements in aerobic capacity ([Formula: see text], + 0.17 ± 0.04 L/min; GET, + 0.18 ± 0.05 L/min, P < 0.01; PO-[Formula: see text], ± 23.36 ± 8.37 W; PO-GET, + 17.18 ± 3.07 W, P < 0.05), body composition (SMM, + 0.92 ± 0.17 kg; BF%, - 3.08% ± 0.58%, P < 0.001), and speed up the τ[Formula: see text] (- 8.04 ± 1.57 s, P < 0.001) significantly, extending to better ∆[HHb]/[Formula: see text] ratio (1.18 ± 0.08 to 1.05 ± 0.14). After a period of detraining, the adaptation in body composition and aerobic capacity, as well as the accelerated τ[Formula: see text] were maintained in the HIIT group, but the PO-[Formula: see text] and PO-GET declined below the post-training level (P < 0.05), whereas no changes were reported in controls (P > 0.05). Four weeks of HIIT induced widespread physiological adaptations in females, and the majority of improvements were preserved after 2 weeks of detraining except for power output corresponding to [Formula: see text] and GET.

Rowing exercise increases cardiorespiratory fitness and brachial artery diameter but not traditional cardiometabolic risk factors in spinal cord-injured humans

PURPOSE

This study assessed the effects of upper-body rowing exercise on cardiorespiratory fitness, traditional cardiometabolic risk factors, and vascular health in individuals with spinal cord injury (SCI).

METHODS

Seventeen male and female adults with chronic (> 1 yr) motor-complete and incomplete SCI (level of injury: C4-L3) were randomized to control (CON, n = 9) or exercise (UBROW, n = 8). Participants in UBROW performed 12-week, 3 weekly sessions of 30-min upper-body ergometer rowing exercise, complying with current exercise guidelines for SCI. Cardiorespiratory fitness ([Formula: see text]O2peak), traditional risk factors (lipid profile, glycemic control) as well as inflammatory and vascular endothelium-derived biomarkers (derived from fasting blood samples) were measured before and after 6 (6W) and 12 weeks (12W). Brachial artery resting diameter and flow-mediated dilation (FMD) were determined by ultrasound as exploratory outcomes.

RESULTS

UBROW increased [Formula: see text]O2peak from baseline (15.1 ± 5.1 mL/kg/min; mean ± SD) to 6W (16.5 ± 5.3; P < 0.01) and 12W (17.5 ± 6.1; P < 0.01). UBROW increased resting brachial artery diameter from baseline (4.80 ± 0.72 mm) to 12W (5.08 ± 0.91; P < 0.01), with no changes at 6W (4.96 ± 0.91), and no changes in CON. There were no significant time-by-group interactions in traditional cardiometabolic blood biomarkers, or in unadjusted or baseline diameter corrected FMD. Explorative analyses revealed inverse correlations between changes (∆12W-baseline) in endothelin-1 and changes in resting diameter (r = - 0.56) and FMD% (r = - 0.60), both P < 0.05.

CONCLUSION

These results demonstrate that 12 weeks of upper-body rowing complying with current exercise guidelines for SCI improves cardiorespiratory fitness and increases resting brachial artery diameter. In contrast, the exercise intervention had no or only modest effects on traditional cardiometabolic risk factors. The study was registered at Clinicaltrials.gov (N-20190053, May 15, 2020).

Effect of continuous aerobic exercise on endothelial function: A systematic review and meta-analysis of randomized controlled trials

Background: Current research suggests that continuous aerobic exercise can be effective in improving vascular endothelial function, while the effect between different intensities and durations of exercise is unclear. The aim of this study was to explore the effect of different durations and intensities of aerobic exercise on vascular endothelial function in different populations. Methods: Searches were performed in PubMed, Web of Science, and EBSCO databases. We included studies that satisfied the following criteria: 1) randomized controlled trials (RCTs); 2) including both an intervention and control group; 3) using flow-mediated dilation (FMD) as the outcome measure; and 4) testing FMD on the brachial artery. Results: From 3,368 search records initially identified, 41 studies were eligible for meta-analysis. There was a significant effect of continuous aerobic exercise on improving flow-mediated dilation (FMD) [weighted mean difference (WMD), 2.55, (95% CI, 1.93-3.16), p < 0.001]. Specifically, moderate-intensity [2.92 (2.02-3.825), p < 0.001] and vigorous-intensity exercise [2.58 (1.64-3.53), p < 0.001] significantly increased FMD. In addition, a longer duration [<12 weeks, 2.25 (1.54-2.95), p < 0.001; ≥12 weeks, 2.74 (1.95-3.54), p < 0.001], an older age [age <45, 2.09 (0.78-3.40), p = 0.002; 45 ≤ age <60, 2.25 (1.49-3.01), p < 0.001; age ≥60, 2.62 (1.31-3.94), p < 0.001], a larger basal body mass index (BMI) [20 < BMI < 25, 1.43 (0.98-1.88), p < 0.001; 25 ≤ BMI < 30, 2.49 (1.07-3.90), p < 0.001; BMI ≥ 30, 3.05 (1.69-4.42), p < 0.001], and a worse basal FMD [FMD < 4, 2.71 (0.92-4.49), p = 0.003; 4 ≤ FMD < 7, 2.63 (2.03-3.23), p < 0.001] were associated with larger improvements in FMD. Conclusion: Continuous aerobic exercise, especially moderate-intensity and vigorous-intensity aerobic exercise, contributed to improving FMD. The effect of continuous aerobic exercise on improving FMD was associated with duration and participant's characteristics. Specifically, a longer duration, an older age, a larger basal BMI, and a worse basal FMD contributed to more significant improvements in FMD. Systematic Review Registration: [https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=341442], identifier [CRD42022341442].

Relation of Aortic Waveforms with Gut Hormones following Continuous and Interval Exercise among Older Adults with Prediabetes

Prediabetes raises cardiovascular disease risk, in part through elevated aortic waveforms. While insulin is a vasodilatory hormone, the gut hormone relation to aortic waveforms is less clear. We hypothesized that exercise, independent of intensity, would favor aortic waveforms in relation to gut hormones. Older adults (61.3 ± 1.5 yr; 33.2 ± 1.1 kg/m2) with prediabetes (ADA criteria) were randomized to undertake 60 min of work-matched continuous (CONT, n = 14) or interval (INT, n = 14) exercise for 2 wks. During a 180 min 75-g OGTT, a number of aortic waveforms (applanation tonometry) were assessed: the augmentation pressure (AP) and index (AIx75), brachial (bBP) and central blood pressure (cBP), pulse pressure (bPP and cPP), pulse pressure amplification (PPA), and forward (Pf) and backward pressure (Pb) waveforms. Acylated-ghrelin (AG), des-acylated ghrelin (dAG), GIP, and GLP-1active were measured, and correlations were co-varied for insulin. Independent of intensity, exercise increased VO2peak (p = 0.01) and PPA120min (p = 0.01) and reduced weight (p < 0.01), as well as AP120min (p = 0.02) and AIx75120min (p < 0.01). CONT lowered bSBP (p < 0.02) and bDBP (p < 0.02) tAUC180min more than INT. There were decreases dAG0min related to Pb120min (r = 0.47, p = 0.03), cPP120min (r = 0.48, p = 0.02), and AP120min (r = 0.46, p = 0.02). Declines in AG tAUC60min correlated with lower Pb120min (r = 0.47, p = 0.03) and cPP120min (r = 0.49, p = 0.02) were also found. GLP-1active 0min was reduced associated with lowered AP180min (r = 0.49, p = 0.02). Thus, while CONT exercise favored blood pressure, both intensities of exercise improved aortic waveforms in relation to gut hormones after controlling for insulin.

Three-minute bench step exercise as a countermeasure for acute mental stress-induced arterial stiffening

Acute mental stress (MS) induces a transient increase in arterial stiffness. We verified whether a single bout of bench step (BS) exercise for 3 minutes counteracts acute MS-induced arterial stiffening. Fifteen healthy young men (mean age, 21.7 ± 0.3 years) underwent two experimental trials: rest (RE) and exercise (EX) trials. Following a 5-minute MS task, the participants in the RE trial rested on a chair for 3 minutes (from 10 to 13 minutes after task cessation), whereas those in the EX trial performed the BS exercise for the same duration. The heart-brachial pulse wave velocity (PWV) (hbPWV), brachial-ankle PWV (baPWV), heart-ankle PWV (haPWV), and the cardio-ankle vascular index (CAVI) were measured at baseline and at 5 and 30 minutes after the task. In both trials, significant increases in hbPWV, haPWV, and CAVI occurred at 5 minutes after the task; these elevations persisted until 30 minutes after the task in the RE trial, but significantly decreased to baseline levels in the EX trial. baPWV was significantly elevated at 30 minutes after the task in the RE trial, but not in the EX trial. This study reveals that a 3-minute BS exercise offsets acute MS-induced arterial stiffening.

Roles of Oxidative Stress and Inflammation in Vascular Endothelial Dysfunction-Related Disease

Oxidative stress and chronic inflammation play an important role in the pathogenesis of atherosclerosis. Atherosclerosis develops as the first step of vascular endothelial dysfunction induced by complex molecular mechanisms. Vascular endothelial dysfunction leads to oxidative stress and inflammation of vessel walls, which in turn enhances vascular endothelial dysfunction. Vascular endothelial dysfunction and vascular wall oxidative stress and chronic inflammation make a vicious cycle that leads to the development of atherosclerosis. Simultaneously capturing and accurately evaluating the association of vascular endothelial function with oxidative stress and inflammation would be useful for elucidating the pathophysiology of atherosclerosis, determining treatment efficacy, and predicting future cardiovascular complications. Intervention in both areas is expected to inhibit the progression of atherosclerosis and prevent cardiovascular complications.

The effects of a motorized passive simulated jogging device on descent of the arterial pulse waveform dicrotic notch: A single arm placebo-controlled cross-over trial

Whole Body Periodic Acceleration (WBPA, pGz), is a bed that moves the body headward to forward, adds pulses to the circulation inducing descent of the dicrotic notch (DN) on the pulse waveform with an increase in a/b ratio (a = the height of the pulse waveform and b = the height of the secondary wave). Since the WBPA is large, heavy, and non-portable, we engineered a portable device (Jogging Device, JD). JD simulates passive jogging and introduces pulsations to the circulation. We hypothesized that JD would increase the a/b ratio during and after its use. In Study A, a single-arm placebo-controlled cross-over trial was conducted in24 adults (53.8 ± 14.4 years) using JD or control (CONT) for 30 min. Blood pressure (BPs and BPd) and photoplethysmograph pulse (a/b) were measured at baseline (BL), during 30 min of JD or CONT, and 5 and 60 min after. In Study B (n = 20, 52.2 ± 7 years), a single-arm observational trial of 7 consecutive days of JD on BP and a/b, measured at BL, and after 7 days of JD and 48 and 72 hr after its discontinuation. In Study A, BPs, and BPd decreased during JD by 13% and 16%, respectively, while in CONT both increased by 2% and 2.5%, respectively. The a/b increased by 2-fold and remained greater than 2-fold at all-time points, with no change in a/b during CONT. In Study B, BPs and BPd decreased by 9% and remained below BL, at 72 hr after discontinuation of JD. DN descent also occurred after 7 days of JD with a/b increase of 80% and remained elevated by 60% for at least 72 h. JD improves acute and longer-term vascular hemodynamics with an increase in a/b, consistent with increased effects of nitric oxide (NO). JD may have significant clinical and public health implications.

Cardiovascular risk in patients receiving antihypertensive drug treatment from the perspective of endothelial function

Blood-pressure-lowering therapy with antihypertensive drugs can reduce the risk of cardiovascular morbidity and mortality in patients with hypertension. However, patients treated with antihypertensive drugs generally have a worse prognosis than untreated individuals. Consistent with the results obtained from epidemiological studies, a clinical study showed that endothelial function was impaired more in treated patients with hypertension than in untreated individuals with the same blood pressure level, suggesting that blood-pressure-lowering therapy with currently available antihypertensive drugs cannot restore endothelial function to the level of that in untreated individuals. Several mechanisms of endothelial dysfunction in treated patients are postulated: irreversible damage to the endothelium caused by higher cumulative elevated blood pressure exposure over time; the persistence of the primary causes of hypertension even after the initiation of antihypertensive drug treatment, including an activated renin-angiotensin-aldosterone system, oxidative stress, and inflammation; and higher global cardiovascular risk related not only to conventional cardiovascular risk factors but also to undetectable nonconventional risk factors. Lifestyle modifications/nonpharmacological interventions should be strongly recommended for both untreated and treated individuals with hypertension. Lifestyle modifications/nonpharmacological interventions may directly correct the primary causes of hypertension, which can improve endothelial function and consequently reduce cardiovascular risk regardless of the use or nonuse of antihypertensive drugs.

The effectiveness of bench step exercise for ameliorating acute mental stress-induced arterial stiffening

Purpose

This study aimed to evaluate the effectiveness of bench step (BS) exercise for ameliorating arterial stiffening caused by acute mental stress (MS).

Methods

Fifteen young healthy men participated in two randomized trials: rest (RE) and exercise (EX) trials. Following a 5-min MS task (first task), the RE trial participants rested on a chair for 10 min (from 10 to 20 min after task cessation); the EX trial participants performed BS exercise for the same duration. At 40 min after the first task, the participants performed the same task (second task) again. Heart–brachial pulse wave velocity (PWV) (hbPWV), brachial–ankle PWV (baPWV), heart–ankle PWV (haPWV), and the cardio-ankle vascular index (CAVI) were measured simultaneously at 5, 30, and 50 min after the first task.

Results

Both trials caused significant elevations in hbPWV, haPWV, and CAVI at 5 min after the first task; these changes persisted until 30 min after the task in the RE trial, while they were abolished in the EX trial. baPWV significantly increased at 30 min after the task in the RE trial, but not in the EX trial. After the second task (from 30 to 50 min after the first task), none of the parameters significantly increased in the RE trial, although the values remained above baseline levels. In the EX trial, hbPWV, haPWV, and CAVI showed significant elevations.

Conclusion

Our findings suggest that a 10-min BS exercise after acute MS can counteract stress-induced arterial stiffening, but has only a limited effect against subsequent acute MS.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00421-022-04962-y.

Effects of Exergaming on College Students' Situational Interest, Self-Efficacy, and Motion Sickness

Objective: Given the low levels of physical activity (PA) among U.S. college students, the use of exergaming as a supplement to traditional exercise may promote higher levels of motivation and PA. Therefore, this study’s purpose was to examine the effect of two different exergames on college students’ situational interest (SI), self-efficacy (SE), and equilibrium change (EQC) compared to traditional treadmill walking. Methods: Sixty college students (30 female; Mage = 23.6 ± 4.1 years; MBMI = 23.9 ± 4.0 kg/m2) participated in three separate 20 min exercise sessions: (1) Xbox 360 Kinect Just Dance; (2) Xbox 360 Kinect Reflex Ridge; and (3) traditional treadmill walking at 4.0 mph. Participants’ SI, SE, and EQC were measured after each session using a series of validated surveys. Results: A mixed model analysis of covariance (ANCOVA) with repeated measures evaluated mean differences between exercise sessions for all outcomes. Significant main effects were observed between the three exercise sessions (all p < 0.01). Specifically, Just Dance and Reflex Ridge sessions yielded significantly higher SI scores than treadmill exercise, F (10, 49) = 54.61, p < 0.01, η2 = 0.92. In addition, participants experienced significantly lower EQC in Reflex Ridge than in treadmill exercise, F (2, 58) = 4.26, p = 0.02, η2 = 0.13. No differences were identified for SE. Conclusion: The integration of exergaming into traditional exercise routines may help to promote higher levels of SI but not SE amongst college students. RR exergaming also demonstrated low EQC as compared to traditional exercise. Experimental study designs are warranted to provide additional evidence on the efficacy of exergaming.

BRAF Modulates Stretch-Induced Intercellular Gap Formation through Localized Actin Reorganization

Mechanical forces acting on cell–cell adhesion modulate the barrier function of endothelial cells. The actively remodeled actin cytoskeleton impinges on cell–cell adhesion to counteract external forces. We applied stress on endothelial monolayers by mechanical stretch to uncover the role of BRAF in the stress-induced response. Control cells responded to external forces by organizing and stabilizing actin cables in the stretched cell junctions. This was accompanied by an increase in intercellular gap formation, which was prevented in BRAF knockdown monolayers. In the absence of BRAF, there was excess stress fiber formation due to the enhanced reorganization of actin fibers. Our findings suggest that stretch-induced intercellular gap formation, leading to a decrease in barrier function of blood vessels, can be reverted by BRAF RNAi. This is important when the endothelium experiences changes in external stresses caused by high blood pressure, leading to edema, or by immune or cancer cells in inflammation or metastasis.

Lower-body dynamic exercise reduces wave reflection in healthy young adults

NEW FINDINGS

What is the central question of this study? There is a paradoxical reduction in augmentation index during lower-body dynamic (LBD) exercise in the face of an increase in central pressure. To determine causality, the amplitudes of forward and backward pressure waves were assessed separately using wave separation analysis. What is the main finding and its importance? Reflection magnitude decreased during LBD exercise in healthy young adults and was attributable to an increased forward pressure wave amplitude and decreased backward pressure wave amplitude. This vasoactive response might limit the adverse effects of wave reflection during LBD exercise, optimizing ventricular-arterial interactions.

ABSTRACT

Acute lower-body dynamic (LBD) exercise decreases surrogate measures of wave reflection, such as the augmentation index. However, the augmentation index is influenced by the combined effects of wave reflection timing, magnitude and other confounding factors external to wave reflection, which make it difficult to discern the origin of changes in surrogate measures. The relative contributions of forward (Pf) and backward (Pb) pressure wave amplitudes to central pressure can be determined by wave separation analysis. Reflection magnitude (RM = Pb/Pf) and the timing of apparent wave reflection return can also be determined. We tested the hypothesis that acute LBD exercise decreases RM and reflected wave transit time (RWTT). Applanation tonometry was used to record radial artery pressure waveforms in 25 adults (24 ± 4 years of age) at baseline and during light-, moderate- and vigorous-intensity exercise. Wave separation analysis was conducted offline using a personalized physiological flow wave to determine Pf, Pb, RM and RWTT. The RM decreased during all intensities of exercise compared with baseline (all P < 0.001; baseline, 43 ± 5%; light, 33 ± 6%; moderate, 23 ± 7%; vigorous, 17 ± 5%). The reduction in RM was attributable to the combined effect of increased Pf and decreased Pb during exercise. The RWTT decreased during all intensities of exercise compared with baseline (all P < 0.04; baseline, 156 ± 17 ms; light, 144 ± 15 ms; moderate, 129 ± 16 ms; vigorous, 121 ± 17 ms). Lastly, in a stepwise multilinear regression, Pf, but not Pb and RWTT, contributed to increased central pulse pressure during LBD exercise. These data show that wave reflection decreased and that central pulse pressure is most influenced by Pf during LBD exercise.

Longitudinal Impact of Physical Activity on Brain Pulsatility Index and Cognition in Older Adults with Cardiovascular Risk Factors: A NIRS Study

Recent studies have shown that optical indices of cerebral pulsatility, including cerebral pulse amplitude, are linked to cerebrovascular health. A chronically higher cerebral pulsatility is associated with cognitive decline. Although it is widely known that regular physical activity improves cognitive functions, little is known about the association between physical activity and the optical index of cerebral pulsatility. This study assessed the impact of 12 months of regular physical activity on the changes in the optical index of cerebral pulsatility and explored its association with cognition. A total of 19 older adults (aged 59-79 years) with cardiovascular risk factors (CVRF) completed the study. Low-intensity, short-duration walking as a brief cardiovascular challenge was used to study the impact of regular physical activity on post-walking changes in cerebral pulsatility index. The participants walked on a gym track while a near-infrared spectroscopy (NIRS) device recorded hemodynamics data from the frontal and motor cortex subregions. Our data indicated that 12 months of physical activity was associated with lower global cerebral pulse amplitude, which was associated with higher cognitive scores in executive functions. Further, the global cerebral pulsatility index was reduced after short-duration walking, and this reduction was greater after 12 months of regular physical activity compared with the baseline. This may be an indication of improvement in cerebrovascular response to the cardiovascular challenge after regular physical activity. This study suggests that 12 months of physical activity may support cognitive functions through improving cerebral pulsatility in older adults with CVRF.

Cardiorespiratory responses to acute bouts of high-intensity functional training and traditional exercise in physically active adults

BACKGROUND

High-intensity functional training is a popular form of exercise, but little is known about how it compares to more traditional exercise patterns.

METHODS

Thirty healthy, physically active adults (15 males, 15 females) performed a high-intensity functional training workout (HIFT) and a traditional workout (TRAD). Cardiorespiratory responses were measured during and for 15 min after each workout.

RESULTS

Peak heart rate (males: 187 ± 7 vs. 171 ± 10 bpm, p < .001; females: 191 ± 9 vs. 175 ± 6 bpm, p < .001), peak VO2 (males: 3.80 ± 0.58 vs. 3.26 ± 0.60 L/min, p < .001; females: 2.65 ± 0.26 vs. 2.36 ± 0.21, p < .001), and average 15 min recovery VO2 (males: 1.15 ± 0.20 vs. 0.99 ± 0.17 L/min, p < .001; females: 0.77 ± 0.10 vs. 0.71 ± 0.07 L/min, p = .019) were significantly higher in HIFT vs. TRAD. Aerobic energy expenditure was significantly higher in HIFT compared to TRAD in males (9.01 ± 1.43 vs. 8.53 ± 1.38 kcal/min, p = .002) but was not significantly different between the two workouts in females (6.04 ± 0.53 vs. 5.97 ± 0.50 kcal/min, p = .395). Post-exercise systolic blood pressure (SBP) was significantly higher than pre-exercise SBP following both HIFT (males: 124 ± 13 mmHg pre to 154 ± 28 mmHg post, p < .001; females: 110 ± 7 mmHg pre to 140 ± 15 mmHg post, p < .001) and TRAD (males: 124 ± 13 mmHg pre to 142 ± 16 mmHg post, p = .002; females: 112 ± 8 mmHg pre to 123 ± 10 mmHg post, p = .002), however, HIFT led to a greater increase compared to TRAD in females (p = .001). Post-exercise diastolic blood pressure (DBP) was significantly lower than pre-exercise DBP following both HIFT (males: 77 ± 9 mmHg pre to 64 ± 6 mmHg post, p < .001; females: 71 ± 8 mmHg pre to 64 ± 7 mmHg post, p = .011) and TRAD (males: 82 ± 7 mmHg pre to 72 ± 7 mmHg post, p < .001; females: 73 ± 8 mmHg pre to 65 ± 8 mmHg post, p < .001). Mean arterial blood pressure was unchanged following both workouts.

CONCLUSIONS

High-intensity functional training may be an effective form of exercise for caloric expenditure and may elicit greater cardiorespiratory stress than traditional exercise.

Acute mental stress-caused arterial stiffening can be counteracted by brief aerobic exercise

PURPOSE

Acute mental stress (MS) causes an elevation in pulse wave velocity (PWV), an index of arterial stiffness. In contrast, aerobic exercise acutely decreases arterial stiffness, even in the short term. The present study aimed to examine whether acute MS-caused arterial stiffening can be counteracted by brief aerobic exercise.

METHODS

Thirteen young healthy men (mean age, 20 ± 1 years) participated in two randomized experimental visits where they were subjected to acute MS followed by seated rest (RE) or cycling exercise (EX) trials. Following a 5-min MS task, the participants in the RE trial rested on a chair for 10 min (from 10 to 20 min after the cessation of the task), whereas those in the EX trial cycled at 35% of heart rate reserve for the same duration. Heart-brachial PWV (hbPWV), brachial-ankle PWV (baPWV), heart-ankle PWV (haPWV), and the cardio-ankle vascular index (CAVI) were simultaneously measured at baseline and 5, 30, and 45 min after the task.

RESULTS

Both trials caused significant elevations (P < 0.05) in hbPWV, haPWV, and CAVI at 5 min after the task; subsequently, this persisted until 45 min after the task in the RE trial, whereas the elevations in the EX trial were eliminated. In the RE trial, baPWV significantly increased (P < 0.05) at 30 and 45 min after the task, whereas such an increase was not observed in the EX trial.

CONCLUSION

The findings of the present study reveal that brief aerobic exercise counteracts arterial stiffening caused by acute MS.

Effect of Different Exercise Modalities on Oxidative Stress: A Systematic Review

Exercise-induced benefits are being increasingly recognized in promoting health and preventing diseases. However, initial adaption to exercise response can have different effects on cells, including an increase in the formation of oxidants and inflammatory mediators that ultimately leads to oxidative stress, but this scenario depends on the exercise type and intensity and training status of the individual. Therefore, we aimed to understand the effect of different types of exercise on oxidative stress. Indeed, exercise-induced minimum oxidative stress is required for regulating signaling pathways. According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement, a search for relevant articles was carried out on PubMed/Medline, ISI Web of Science, and Google Scholar using a broad range of synonyms such as oxidants, reactive oxygen species (ROS), oxidative stress, exercise, physical training, aerobic exercise, and strength exercise until 2019. This study selected a total of 18 articles for assessing the oxidative damage using various parameters such as malondialdehyde (MDA), protein carbonyl (PCO), and F1-isoprostanes and enzymatic antioxidants. We observed that any type of exercise can increase the oxidative damage in an exercise type and intensity manner. Further, the training status of the individual and specific oxidative damage marker plays a crucial role in predicting earlier oxidative damage in the exercise condition. However, some of the studies that we included for review did not perform follow-up evaluations. Therefore, follow-up programs using larger numbers need to be performed to confirm our findings.

Nitric oxide and its role in exercise physiology

INTRODUCTION

Nitric oxide (NO) is quite an essential molecule for human metabolism since it plays an active role in body functions. In the past 20 years, nitric oxide has become a milestone in terms of both athlete physiology and pharmacology studies. The most known and remarkable function of NO is its role in controlling vasodilatation, blood rate, and mitochondrial respiration and thus enhance performance. Therefore, it can be argued that exercise and NO have a positive relationship.

EVIDENCE ACQUISITION

In the scientific literature search related to this review, the US National Library of Medicine (PubMed) used MEDLINE and SportDiscus data and the terms "NO," "physical exercise," "vasodilatation," and "performance enhancement." The relevant literature took its source from the research of relevant articles from reference lists derived from data studies.

EVIDENCE SYNTHESIS

It was observed that there is a relationship between physical activity and nitric oxide, and it is demonstrated that physical activity enhances NO production. NO is supposed to improve sports performance, promote recovery, and benefit the athlete's health with its physiological support in vasodilatation, blood flow, and mitochondrial respiration.

CONCLUSIONS

Physical activity and nitric oxide resulted to be related. There is a concrete evidence that physical activity enhances NO production. Exercise should be recommended for increasing the level of NO for athletes and for patients with cardiovascular disorders for therapy.

Acute Effects of Different Intensities of Cycling Acute Exercise on Carotid Arterial Apparent Elasticity and Hemodynamic Variables

Background

Cardiovascular disease (CVD) is closely related to arterial elasticity and hemodynamics. Exercises have been reported to immediately decrease arterial apparent elasticity and regulate hemodynamic variables. However, the relationship between them and exercise intensity remains elusive. The purpose of this study was to determine the acute effects of different intensities of acute cycling exercise on carotid arterial apparent elasticity and hemodynamics.

Methods

32 healthy men (age: 19.4 ± 0.6 years) attended the laboratory on five occasions and completed cycling acute exercise for 20 minutes at five intensities (40%, 50%, 60%, 70%, and 80% heart rate reserve (HRR)). At the right carotid artery, center-line velocity and arterial inner diameter waveforms were examined before and immediately after exercise. Based upon the measured data, the classical hemodynamic theory was used to calculate the apparent elasticity and the local hemodynamic variables.

Results

The arterial apparent stiffness and the apparent elastic modulus following acute cycling exercise at 60% to 80% HRR were significantly higher than baseline. The mean center-line velocity accelerated from 50% to 80% HRR, but no intensity of intervention altered mean blood flow. Immediately after intervention, the mean wall shear stress and oscillatory shear index increased.

Conclusions

Aerobic cycling intervention, with intensity from 40% to 80% HRR, did not change the brain blood supply. A bout of cycling intervention decreased apparent elasticity, and there was an intensity-dependent effect on apparent elasticity and hemodynamic variables. This study would provide referable data for the further study on the effects of aerobic exercise on arterial hemodynamics and elasticity and underlying physiological mechanisms.

Profile of blood pressure and glycemic responses after interval exercise in older women attending (in) a public health physical activity program

BACKGROUND

and purpose: Interval exercise causes a positive impact on health status. Our aim was to evaluate the effects of a feasible and low-cost interval exercise on blood pressure and glycemic responses in people with controlled systemic arterial hypertension.

METHODS

Thirteen women with hypertension (HG; age: 60.2 ± 2.8 years) and 11 without hypertension (CG; age: 54.4 ± 3.8 years) were recruited. Groups performed one session of interval exercise with elastic resistance (10 series of 1:1 min/effort:rest).

RESULTS

There were slight reductions of absolute systolic blood pressure values for HG at 10, 30, and 60 min (4, 9, and 8 mmHg, respectively) at post-compared to pre-exercise. Glycemia was reduced (respectively, 17.6%, 17.6%, 19.4%, and 23.1%; p < 0.05) at pre-exercise vs. 0 min and 10, 30, and 60 min post-exercise for the HG.

CONCLUSION

A single session of a feasible and low-cost interval exercise modifies and promotes significant clinical effects in blood pressure and glycemic levels in female older adults with and without hypertension.

Endocrine Mechanisms Connecting Exercise to Brown Adipose Tissue Metabolism: a Human Perspective

PURPOSE OF REVIEW

To summarize the state-of-the-art regarding the exercise-regulated endocrine signals that might modulate brown adipose tissue (BAT) activity and/or white adipose tissue (WAT) browning, or through which BAT communicates with other tissues, in humans.

RECENT FINDINGS

Exercise induces WAT browning in rodents by means of a variety of physiological mechanism. However, whether exercise induces WAT browning in humans is still unknown. Nonetheless, a number of protein hormones and metabolites, whose signaling can influence thermogenic adipocyte's metabolism, are secreted during and/or after exercise in humans from a variety of tissues and organs, such as the skeletal muscle, the adipose tissue, the liver, the adrenal glands, or the cardiac muscle. Overall, it seems plausible to hypothesize that, in humans, exercise secretes an endocrine cocktail that is likely to induce WAT browning, as it does in rodents. However, even if exercise elicits a pro-browning endocrine response, this might result in a negligible effect if blood flow is restricted in thermogenic adipocyte-rich areas during exercise, which is still to be determined. Future studies are needed to fully characterize the exercise-induced secretion (i.e., to determine the effect of the different exercise frequency, intensity, type, time, and volume) of endocrine signaling molecules that might modulate BAT activity and/or WAT browning or through which BAT communicates with other tissues, during exercise. The exercise effect on BAT metabolism and/or WAT browning could be one of the still unknown mechanisms by which exercise exerts beneficial health effects, and it might be pharmacologically mimicked.

Effects of isometric resistance training on resting blood pressure: individual participant data meta-analysis

Background:

Previous meta-analyses based on aggregate group-level data report antihypertensive effects of isometric resistance training (IRT). However, individual participant data meta-analyses provide more robust effect size estimates and permit examination of demographic and clinical variables on IRT effectiveness.

Methods:

We conducted a systematic search and individual participant data (IPD) analysis, using both a one-step and two-step approach, of controlled trials investigating at least 3 weeks of IRT on resting systolic, diastolic and mean arterial blood pressure.

Results:

Anonymized individual participant data were provided from 12 studies (14 intervention group comparisons) involving 326 participants (52.7% medicated for hypertension); 191 assigned to IRT and 135 controls, 25.2% of participants had diagnosed coronary artery disease. IRT intensity varied (8–30% MVC) and training duration ranged from 3 to 12 weeks. The IPD (one-step) meta-analysis showed a significant treatment effect for the exercise group participants experiencing a reduction in resting SBP of −6.22 mmHg (95% CI −7.75 to −4.68; P < 0.00001); DBP of −2.78 mmHg (95% CI −3.92 to −1.65; P = 0.002); and mean arterial blood pressure (MAP) of −4.12 mmHg (95% CI −5.39 to −2.85; P < 0.00001). The two-step approach yielded similar results for change in SBP −7.35 mmHg (−8.95 to −5.75; P < 0.00001), DBP MD −3.29 mmHg (95% CI −5.12 to −1.46; P = 0.0004) and MAP MD −4.63 mmHg (95% CI −6.18 to −3.09: P < 0.00001). Sub-analysis revealed that neither clinical, medication, nor demographic participant characteristics, or exercise program features, modified the IRT treatment effect.

Conclusion:

This individual patient analysis confirms a clinically meaningful and statistically significant effect of IRT on resting SBP, DBP and mean arterial blood pressure.

Comparison of College Students' Blood Pressure, Perceived Exertion, and Psychosocial Outcomes During Virtual Reality, Exergaming, and Traditional Exercise: An Exploratory Study

Objective: Integrating novel technologies, such as virtual reality (VR), into traditional exercise apparatuses (e.g., stationary bikes) may assist in promoting physical activity (PA) participation among young adults. Therefore, this study's purpose was to examine young adults' systolic and diastolic blood pressure (BP) change (BP_post - BP_pre), rating of perceived exertion (RPE), enjoyment, and self-efficacy during VR, exergaming, and traditional stationary cycling sessions. Materials and Methods: Forty-nine college students (34 females; M_age = 23.6 ± 3.4 years; M_BMI = 23.8 ± 3.1 kg/m²) participated in three separate 20-minute stationary cycling sessions: (1) PlayStation 4 VR; (2) Xbox 360 exergaming; and (3) traditional stationary cycling. Participants' systolic and diastolic BP change was measured by using an Omron HEM-705CP digital BP cuff. Further, RPE was assessed by using the modified Borg RPE Scale and enjoyment and self-efficacy were evaluated by using validated questionnaires. Results: A multivariate analysis of variance indicated significant differences for systolic BP change, RPE, enjoyment, and self-efficacy between the three cycling sessions (F(2, 144) = 3.3-32.4, P < 0.05, [Formula: see text] = 0.04-0.3). Specifically, participants had significantly higher enjoyment and self-efficacy and lower RPE during VR cycling compared with the other two cycling sessions despite similar or higher change systolic BP during the VR cycling session. There was no statistically significant change in diastolic BP between the three cycling sessions (P > 0.05). Conclusion: Incorporating VR equipment with traditional stationary cycle ergometers may be favorable when seeking to promote enjoyable PA in college students. To further support VR exercise's efficacy, future studies with more rigorous research designs are warranted.

Effects of Unilateral Arm Warming or Cooling on the Modulation of Brachial Artery Shear Stress and Endothelial Function during Leg Exercise in Humans

Aim: We examined the effect of modulating the shear stress (SS) profile using forearm warming and cooling on subsequent endothelial function in the brachial artery (BA) during exercise.

Methods: Twelve healthy young subjects immersed their right forearm in water (15°C or 42°C) during a leg cycling exercise at 120–130 bpm for 60 min. The same exercise without water immersion served as a control. The BA diameter and blood velocity were simultaneously recorded using Doppler ultrasonography to evaluate the antegrade, retrograde, and mean shear rates (SRs, an estimate of SS) before, during, and after exercise. The endothelial function in the right BA was evaluated using flow-mediated dilation (FMD) (%) using two-dimensional high-resolution ultrasonography before (baseline) and 15 and 60 min after exercise.

Results: During exercise, compared with the control trial, higher antegrade and mean SRs and lower retrograde SRs were observed in the warm trial; conversely, lower antegrade and mean SRs and higher retrograde SRs were observed in the cool trial. At 15 min postexercise, no significant change was observed in the FMD from baseline in the warm (Δ%FMD: +1.6%, tendency to increase; p = 0.08) and control trials (Δ %FMD: +1.1%). However, in the cool trial, the postexercise FMD at 60 min decreased from baseline (Δ%FMD: −2.7%) and was lower than that of the warm (Δ%FMD: +1.5%) and control (Δ%FMD: +1.2%) trials. Accumulated changes in each SR during and after exercise were significantly correlated with postexercise FMD changes.

Conclusion: Modulation of shear profiles in the BA during exercise appears to be associated with subsequent endothelial function.

Acute Effects of Resistance Exercise and the Use of GH or IGF-1 Hormones on Oxidative Stress and Antioxidant Markers in Bodybuilders

The aim of this study was to examine the influence of peptide hormone use on oxidative stress and antioxidant responses to a single session of resistance exercise in male bodybuilders. Forty-five male bodybuilders were divided into three groups: bodybuilders using growth hormone for at least 1 year (i.e., 3 to 4 times in the year) (GH-user, n = 15), bodybuilders using insulin-like growth factor-1 for at least 1 year (i.e., 3 to 4 times in the year) (IGF-1-user, n = 15), and peptide hormone-free bodybuilders (Non-user, n = 15). The heavy resistance exercise protocol consisted of five sets with 80% of one repetition maximum for six exercises. Blood samples were obtained pre and post heavy resistance exercise (HRE) in order to evaluate changes in oxidative stress (8-hydroxy-2-deoxyguanosine (8-OHdG), malondialdehyde (MDA), and nitric oxide (NO)) and antioxidant biomarkers (glutathione peroxidase (GPx), catalase (CAT) and glutamate (GLU)) level. All the experimental groups showed increases in MDA (p = 0.038), NO (p = 0.028), GPx (p = 0.012), and GLU (p = 0.003) concentrations after resistance exercise. For 8-OHdG, the Non-user and IGF-1-user groups indicated increases at post-exercise (p = 0.001), without any significant changes in the GH-user group (p = 0.87). In addition, the changes in serum GPx and GLU levels were greater for the GH-user group than the Non-user and IGF-1-user groups (p = 0.001). In conclusion, HRE induced significant increases in 8-OHdG (except to GH-user group), MDA, NO, GPx, and GLU levels with greater changes in GPx and GLU for the GH-user group.

High Bubble Grade After Diving: The Role of the Blood Pressure Regimen

Introduction: Previous studies have suggested that the circulatory system was involved in the production of circulatory bubbles after diving. This study was designed to research the cardio-vascular function characteristics related to the production of high bubble grades after diving.

Methods: Thirty trained divers were investigated both at baseline and after a 30-msw SCUBA dive. At baseline, the investigations included blood pressure measurement, echocardiography, and assessment of aerobic fitness using VO₂ peak measurement. Blood samples were taken at rest, to measure the plasma concentration of NOx and endothelin-1. After diving, circulating bubbles were detected in the pulmonary artery by pulsed Doppler at 20-min intervals during the 90 min after surfacing. The global bubble quantity production was estimated by the KISS index.

Results: Divers with a high bubble grade (KISS > 7.5) had systolic blood pressure, pulse pressure, weight, and height significantly higher than divers with a low bubble grade. By contrast, total arterial compliance, plasma NOx level, and percentage of predicted value of peak oxygen uptake were significantly lower in divers with a high bubble grade. Cardiac dimensions, left ventricular function, and plasma endothelin-1 concentration were not significantly different between groups. The multivariate analysis identified blood pressure as the main contributor of the quantity of bubble production. The model including pulse pressure, plasma NOx level, and percentage of predicted value of peak oxygen uptake has an explanatory power of 49.22%.

Conclusion: The viscoelastic properties of the arterial tree appeared to be an important contributor to the circulating bubble production after a dive.

Impairment between Oxidant and Antioxidant Systems: Short- and Long-term Implications for Athletes' Health

The role of oxidative stress, an imbalance between reactive oxygen species production (ROS) and antioxidants, has been described in several patho-physiological conditions, including cardiovascular, neurological diseases and cancer, thus impacting on individuals' lifelong health. Diet, environmental pollution, and physical activity can play a significant role in the oxidative balance of an organism. Even if physical training has proved to be able to counteract the negative effects caused by free radicals and to provide many health benefits, it is also known that intensive physical activity induces oxidative stress, inflammation, and free radical-mediated muscle damage. Indeed, variations in type, intensity, and duration of exercise training can activate different patterns of oxidant-antioxidant balance leading to different responses in terms of molecular and cellular damage. The aim of the present review is to discuss (1) the role of oxidative status in athletes in relation to exercise training practice, (2) the implications for muscle damage, (3) the long-term effect for neurodegenerative disease manifestations, (4) the role of antioxidant supplementations in preventing oxidative damages.

Prior cycling exercise does not prevent endothelial dysfunction after resistance exercise

PURPOSE

Resistance exercise impairs endothelial function acutely. Therefore, it becomes important to devise an effective strategy for preventing acute endothelial dysfunction after resistance exercise. Herein, we tested the hypothesis that resistance exercise-induced temporal endothelial dysfunction is prevented by prior cycling.

METHODS

Twelve young healthy subjects completed two randomized experimental trials: (1) resistance exercise only trial (RE trial), (2) resistance exercise with prior cycling trial (C + RE trial). Following baseline brachial artery flow-mediated dilation (FMD), the subjects maintained the supine position for 45 min in the RE trial; the subjects performed a 45 min of cycling (67.0 ± 1.7% HRmax) in the C + RE trial. After 45 min of resting or cycling, the subjects performed resistance exercise (69.7 ± 4.0 kg) at the same time points. Following the resistance exercise, they were asked to rest in the supine position for 60 min. Then FMD were repeated at 10, 30 and 60 min after the resistance exercise in both trials.

RESULTS

The increased blood flow and shear rate after resistance exercise did not differ between trials, and these changes disappeared following resting in the supine position for 60 min. There was no significant interaction in %FMD responses. Both trials caused impairment in %FMD after the resistance exercise, and statistical significance was observed at 30 and 60 min after resistance exercise in the RE trial.

CONCLUSION

The present study revealed that cycling for 45 min prior to resistance exercise was not sufficient to prevent the acute endothelial dysfunction after resistance exercise.

Short-term cycling restores endothelial dysfunction after resistance exercise

Resistance exercise impairs endothelial function. Therefore, it is of paramount importance to devise an effective strategy for restoring endothelial function after resistance exercise. Herein, we tested the hypothesis that resistance exercise-induced endothelial dysfunction would be restored by low-to-moderate intensity cycling. Seventeen young healthy subjects completed two randomized experimental trials: (a) resistance exercise only trial; and (b) cycling after the resistance exercise trial. Following baseline brachial artery flow-mediated dilation (FMD), subjects performed the resistance exercise. Following the resistance exercise, they were asked to rest in the supine position for the assessments of FMD. Subjects in the resistance exercise only trial maintained this supine position for 60 minutes, whereas those in the other trial cycled for 10 minutes after the resistance exercise trial. Subjects were again asked to rest in the supine position after cycling. Then FMD were repeated at 30 and 60 minutes after the resistance exercise in both trials. In the resistance exercise only trial, the increased blood flow and shear rate were disappeared after 1 hour of resting in the supine position, but were maintained in those in the cycling after the resistance trial due to subsequent cycling. Both trials caused a significant impairment in FMD at 10 minutes after the resistance exercise (P < 0.05). This decline was sustained for 60 minutes in the resistance exercise only trial. However, the impaired FMD was restored in the cycling after the resistance exercise trial. In conclusion, impaired endothelial function after the resistance exercise can be restored with 10 minutes of low-to-moderate intensity cycling.

The effects of a 12-week jump rope exercise program on abdominal adiposity, vasoactive substances, inflammation, and vascular function in adolescent girls with prehypertension

INTRODUCTION

Childhood obesity is strongly associated with cardiovascular disease (CVD) development. It is necessary to combat unfavorable outcomes of obesity at a young age by utilizing effective interventions, such as exercise.

PURPOSE

We sought to examine the effects of a jump rope exercise program on CVD risk factors, including body composition, vasoactive substances, inflammation, and vascular function in prehypertensive adolescent girls.

METHODS

Forty girls (age 14-16) were recruited and randomly assigned to a jump rope exercise group (EX, n = 20) or control group (CON, n = 20). Body composition, nitrate and nitrite levels, endothelin-1 (ET-1), C-reactive protein (CRP), systolic blood pressure and diastolic blood pressure (SBP, DBP), and arterial stiffness were measured before and after 12 weeks.

RESULTS

There were significant group by time interactions following the 12-week program for body composition (from 33.8 ± 3.6 to 30.2 ± 3.1%), central adiposity (from 86.4 ± 4 to 83.3 ± 5 cm), SBP (from 126 ± 3.3 to 120 ± 2.1 mmHg), and brachial-to-ankle pulse wave velocity (from 8.2 ± 1.0 to 7.4 ± 0.2 m/s). Nitrate/nitrite levels increased (from 54.5 ± 5.1 to 57.2 ± 5.2 µmol) along a reduction in CRP levels (from 0.5 ± 0.4 to 0.2 ± 0.1 mg/L). There were no significant changes in ET-1 (P = 0.22).

CONCLUSIONS

These findings indicate that jump rope exercise may be an effective intervention to improve these CVD risk factors in prehypertensive adolescent girls. Jumping rope is an easily accessible exercise modality that may have important health implications for CVD prevention in younger populations.

Molecular hydrogen reduces acute exercise-induced inflammatory and oxidative stress status

Physical exercise induces inflammatory and oxidative markers production in the skeletal muscle and this process is under the control of both endogenous and exogenous modulators. Recently, molecular hydrogen (H2) has been described as a therapeutic gas able to reduced oxidative stress in a number of conditions. However, nothing is known about its putative role in the inflammatory and oxidative status during a session of acute physical exercise in sedentary rats. Therefore, we tested the hypothesis that H2 attenuates both inflammation and oxidative stress induced by acute physical exercise. Rats ran at 80% of their maximum running velocity on a closed treadmill inhaling either the H2 gas (2% H2, 21% O2, balanced with N2) or the control gas (0% H2, 21% O2, balanced with N2) and were euthanized immediately or 3 h after exercise. We assessed plasma levels of inflammatory cytokines [tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6] and oxidative markers [superoxide dismutase (SOD), thiobarbituric acid reactive species (TBARS) and nitrite/nitrate (NOx)]. In addition, we evaluated the phosphorylation status of intracellular signaling proteins [glycogen synthase kinase type 3 (GSK3α/β) and the cAMP responsive element binding protein (CREB)] that modulate several processes in the skeletal muscle during exercise, including changes in exercise-induced reactive oxygen species (ROS) production. As expected, physical exercise increased virtually all the analyzed parameters. In the running rats, H2 blunted exercise-induced plasma inflammatory cytokines (TNF-α and IL-6) surges. Regarding the oxidative stress markers, H2 caused further increases in exercise-induced SOD activity and attenuated the exercise-induced increases in TBARS 3 h after exercise. Moreover, GSK3α/β phosphorylation was not affected by exercise or H2 inhalation. Otherwise, exercise caused an increased CREB phosphorylation which was attenuated by H2. These data are consistent with the notion that H2 plays a key role in decreasing exercise-induced inflammation, oxidative stress, and cellular stress.

Comparison of Cardiac and Vascular Parameters in Powerlifters and Long-Distance Runners: Comparative Cross-Sectional Study

BACKGROUND

Cardiac remodeling is a specific response to exercise training and time exposure. We hypothesized that athletes engaging for long periods in high-intensity strength training show heart and/or vascular damage.

OBJECTIVE

To compare cardiac characteristics (structure and function) and vascular function (flow-mediated dilation [FMD] and peripheral vascular resistance [PVR]) in powerlifters and long-distance runners.

METHODS

We evaluated 40 high-performance athletes (powerlifters [PG], n = 16; runners [RG], n = 24) and assessed heart structure and function (echocardiography), systolic and diastolic blood pressure (SBP/DBP), FMD, PVR, maximum force (squat, bench press, and deadlift), and maximal oxygen uptake (spirometry). A Student's t Test for independent samples and Pearson's linear correlation were used (p < 0.05).

RESULTS

PG showed higher SBP/DBP (p < 0.001); greater interventricular septum thickness (p < 0.001), posterior wall thickness (p < 0.001) and LV mass (p < 0.001). After adjusting LV mass by body surface area (BSA), no difference was observed. As for diastolic function, LV diastolic volume, wave E, wave e', and E/e' ratio were similar for both groups. However, LA volume (p = 0.016) and BSA-adjusted LA volume were lower in PG (p < 0.001). Systolic function (end-systolic volume and ejection fraction), and FMD were similar in both groups. However, higher PVR in PG was observed (p = 0.014). We found a correlation between the main cardiovascular changes and total weight lifted in PG.

CONCLUSIONS

Cardiovascular adaptations are dependent on training modality and the borderline structural cardiac changes are not accompanied by impaired function in powerlifters. However, a mild increase in blood pressure seems to be related to PVR rather than endothelial function.

Comparison of College Students' Energy Expenditure, Physical Activity, and Enjoyment during Exergaming and Traditional Exercise

This study evaluated the effects of exergaming on college students’ energy expenditure (EE), moderate-to-vigorous physical activity (MVPA), light physical activity (LPA), rating of perceived exertion (RPE), and enjoyment compared to traditional treadmill exercise, and sex differences. Sixty college students (30 female; X¯_age = 23.6 ± 4.1 years) completed three 20-min exercise sessions on Xbox 360 Kinect Just Dance (Microsoft, Redmond, WA, USA), Xbox 360 Kinect Reflex Ridge (Microsoft, Redmond, WA, USA), and treadmill walking. Their EE and PA were assessed by ActiGraph accelerometers (ActiGraph Co.; Pensacola, FL, USA); RPE every four min; enjoyment via an established scale. Significant exercise-type by sex interaction effects were observed for RPE (p < 0.01): females reported significantly lower RPE during exergaming sessions but significantly higher RPE during treadmill walking. Results revealed significant main effects for all outcomes between exercise sessions (all p < 0.01): treadmill walking resulted in significantly higher metabolic equivalents (METs), MVPA, and EE (p < 0 .01), yet lower LPA (p < 0.01), compared to the two exergaming sessions. Participants’ RPE was significantly higher during treadmill walking than during exergaming sessions, with exergaming eliciting significantly higher enjoyment (all p < 0.01). College students find exergaming more enjoyable and report lower RPE compared to traditional treadmill exercise, though not yet matching the moderate physiological intensity level.

Acute and chronic effects of soccer game on the retinal vessel diameters in middle-aged adults

BACKGROUND

Although changes in retinal vessel diameter is a new biomarker for the evaluation of cardiovascular risk factors, limited information is available regarding the effects of endurance exercises on retinal microcirculation. Thus, we aimed to evaluate both chronic and acute effects of soccer game on the diameters of retinal vessels in middle-aged players.

METHODS

Retinal vessel diameters were measured in 12 middle-aged amateur players (44.4±7.0 years of age) with more than four years of soccer playing experience and 12 age-matched sedentary adults (49.7±7.1 years of age). In soccer players, diameters were also measured immediately after the soccer game. Cardiovascular risk profiles (anthropometry and body composition and blood pressure [BP]) and physical activity levels were also measured.

RESULTS

Soccer players had wider retinal vessels than controls (P<0.05), resulting in greater arteriolar-to-venular diameter ratio (AVR) (P<0.05). Greater sports-related physical activity, lower body mass index (BMI) and fat mass were observed for soccer players compared to the controls (P<0.05), whereas BP did not differ. Physical activity level correlated positively with temporal retinal arteriolar (TRA) diameter and with AVR (P<0.05), whereas TRA diameter correlated negatively with BMI and fat mass (P<0.05). A significant correlation between temporal retinal venule (TRV) diameter and TRA diameter (P<0.05) was observed. The acute soccer game increased BP (P<0.05) and induced TRV dilatation (P<0.05).

CONCLUSIONS

In middle-aged amateur soccer players, improvement of the retinal microcirculation was observed. Cardiovascular risk factors and physical inactivity were associated with adverse retinal microvascular alterations. In terms of acute effects, soccer play causes venular, but not arteriolar dilatation for middle-aged adults.

Flow does not alter eNOS phosphoryation at Ser1179 or Thr495 in preconstricted mouse mesenteric arteries

In arteries, endothelium-dependent vasodilatory agonists and flow-induced shear stress cause vasodilation largely by activation of the endothelial enzyme eNOS, which generates nitric oxide that relaxes vascular smooth muscle. Agonists activate eNOS in part through increased phosphorylation at Ser1179 and decreased phosphorylation at Thr495. We previously found that preconstriction of intact, isolated mouse mesenteric arteries with phenylephrine also caused increased Ser1179 and decreased Thr495 eNOS phosphorylation, and sequential treatment with the vasodilatory agonist acetylcholine did not cause any further change in phosphorylation at these sites, despite producing vasodilation. The present study tests the hypothesis that luminal flow in these arteries preconstricted with phenylephrine also produces vasodilation without phosphorylation changes at these sites. First-order mesenteric arteries, isolated from male C57/BL6 mice (7-20 weeks of age) anesthetized with pentobarbital (50 mg/kg, i.p.), were cannulated, pressurized, and treated with stepped increases in luminal flow (15-120 μL/min). Flow resulted in dilation that plateaued at ~60 μL/min (31.3 ± 3.0% dilation) and was significantly (P < 0.001) NOS-dependent at all flow rates (determined by 10-4 mol/L L-NAME treatment). In separate arteries, preconstriction with phenylephrine (10-5 mol/L) resulted in increased eNOS phosphorylation at Ser1179 (P < 0.05) and decreased phosphorylation at Thr495, but subsequent flow at 60 μL/min for 5 or 15 min did not cause further changes in phosphorylation, despite causing dilation. Thus, flow-induced dilation does not require changes in these eNOS phosphorylation sites beyond those induced by alpha1-adrenergic stimulation with phenylephrine, indicating that eNOS is activated by other mechanisms during acute flow-induced dilation of preconstricted arteries.

Acute effects of walking in water on vascular endothelial function and heart rate variability in healthy young men

AIM

Aquatic exercise might improve endothelial function due to hydrostatic pressure increasing blood flow and causing shear stress to the endothelium. However, the acute effect of aerobic exercise in water on endothelial function is unclear. The present study compares the acute effect of aerobic exercise at moderate intensity in water and on land on endothelial function.

METHODS

Nine healthy young men walked on a treadmill for 30 min while immersed in water up to the xiphoid at 30.0 ± 0.2°C and on land at an intensity equivalent to 60% heart rate reserve in a crossover trial. Brachial artery flow-mediated dilation (FMD) was measured at baseline and at 30 and 60 min after exercise. Autonomic nervous activity was compared among conditions at the heart rate variability (HRV) during exercise.

RESULTS

FMD significantly decreased at 30 min after exercise on land trial (p < 0.05), but did not change after the aquatic trial. However, FMD was significantly higher after aquatic trial than land trial (p < 0.05) at 30 and 60 min after exercise, whereas heart rate, blood pressure, and HRV did not significantly differ between them.

CONCLUSION

These findings demonstrate that aerobic exercise in water suppressed the decrease in FMD compared with that on land, regardless of autonomic nervous activity.

Conditioned medium from contracting skeletal muscle cells reverses insulin resistance and dysfunction of endothelial cells

OBJECTIVE

Obese adipose tissue has been characterized with chronic inflammation associated with elevated secretion of inflammatory cytokines and declined secretion of anti-inflammatory cytokines which can impair endothelial function in an endocrine manner. Adipose tissue hypoxia plays a role in the changes of cytokines. Physical exercise/muscle contraction may help preventing cardiovascular disease through improving insulin resistance and endothelium function. However the mechanism is unclear. Skeletal muscle is an endocrine tissue. Contracting muscles secrete myokines which may play roles in the beneficial effect of exercise. In this study, the conditioned medium from electrical pulse stimulation (EPS) regulated skeletal muscle cells was used to explore the mechanism of contraction on endothelial dysfunction and insulin resistance induced by conditioned medium from hypoxic adipocytes.

METHODS

3T3-L1 adipocytes were incubated under normoxia or hypoxia condition, respectively. The supernatant was collected as adipocyte conditioned medium (CM-N and CM-H). C2C12 mouse skeletal muscle cells were stimulated with EPS for 12 h. The supernatant was collected as muscle cells conditioned medium (CM-EPS). Human umbilical vein endothelial cells (HUVECs) were incubated with adipocyte CM and muscle cells CM together. Macrophages migration to HUVECs was detected with transwell system. The mRNA expressions of E-selectin, ICAM-1, MCP-1 and IL-6 were measured by real-time PCR. The phosphorylation of IKKα/β, NF-κB, Akt, AMPK, eNOS and SOCS3 protein levels were detected by Western blot. Concentration of NO was measured by ELISA kit. HUVECs apoptosis was detected by flow cytometry.

RESULTS

CM-EPS reduced the increase of mRNA expressions of E-selectin, ICAM-1, MCP-1 and IL-6 in HUVECs induced by CN-H. The phosphorylations of IKKα/β and NF-κB, SOCS3 protein level and endothelial cells apoptosis, which were raised by CM-H, were significantly reduced by CM-EPS. CM-EPS reversed the effects of CM-H on Akt and eNOS phosphorylations and NO production in HUVECs. CM-EPS directly stimulated the phosphorylation of AMPK, which caused the following phosphorylation of eNOS in HUVECs.

CONCLUSION

In summary, CM-EPS reversed endothelial cells inflammation, apoptosis, insulin resistance and dysfunction induced by CM-H.

Effects of prior aerobic exercise on sitting-induced vascular dysfunction in healthy men

INTRODUCTION

Acute aerobic exercise prevents sitting-induced impairment of flow-mediated dilation (FMD). Further, evidence suggests that sitting-induced impairment of FMD occurs via an oxidative stress-dependent mechanism that disrupts endothelial function.

PURPOSE

We hypothesized that acute aerobic exercise would prevent impairment of femoral artery FMD by limiting oxidative stress responses that increase endothelin-1 (ET-1) levels and disrupt nitric oxide (NO) status.

METHODS

In a randomized, cross-over study, healthy men (n = 11; 21.2 ± 1.9 years) completed two 3 h sitting trials that were preceded by 45 min of either quiet rest (REST) or a single bout of continuous treadmill exercise (65% maximal oxygen consumption) (EX). Superficial femoral artery FMD, plasma glucose, malondialdehyde (MDA), ET-1, arginine (ARG) and its related metabolites [homoarginine (HA), asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA)] were assessed at baseline, 1 h following EX (or REST) (0 h), and at 1 h intervals during 3 h of uninterrupted sitting. Data were analyzed using repeated measures ANOVA.

RESULTS

During REST, femoral artery FMD declined from baseline (2.6 ± 1.8%) at 1, 2, and 3 h of sitting and resting shear rate decreased at 3 h. In contrast, when sitting was preceded by EX, femoral artery FMD (2.7 ± 2.0%) and resting shear rate responses were unaffected. No between trial differences were detected for plasma glucose, MDA, ET-1, ARG, HA, ADMA, or SDMA.

CONCLUSION

Prior aerobic exercise prevented the decline in femoral artery FMD that is otherwise induced by prolonged sitting independent of changes in oxidative stress, ET-1, and NO status.

A Single Resistance Exercise Session Improves Aortic Endothelial Function in Hypertensive Rats

BACKGROUND

Physical exercise is an important tool for the improvement of endothelial function.

OBJECTIVE

To assess the effects of acute dynamic resistance exercise on the endothelial function of spontaneously hypertensive rats (SHR).

METHODS

Ten minutes after exercise, the aorta was removed to evaluate the expression of endothelial nitric oxide synthase (eNOS), phosphorylated endothelial nitric oxide synthase (p-eNOS1177) and inducible nitric oxide synthase (iNOS) and to generate concentration-response curves to acetylcholine (ACh) and to phenylephrine (PHE). The PHE protocol was also performed with damaged endothelium and before and after NG-nitro-L-arginine methyl ester (L-NAME) and indomethacin administration. The maximal response (Emax) and the sensitivity (EC50) to these drugs were evaluated.

RESULTS

ACh-induced relaxation increased in the aortic rings of exercised (Ex) rats (Emax= -80 ± 4.6%, p < 0.05) when compared to those of controls (Ct) (Emax = -50 ± 6.8%). The Emax to PHE was decreased following exercise conditions (95 ± 7.9%, p < 0.05) when compared to control conditions (120 ± 4.2%). This response was abolished after L-NAME administration or endothelial damage. In the presence of indomethacin, the aortic rings' reactivity to PHE was decreased in both groups (EC50= Ex -5.9 ± 0.14 vs. Ct -6.6 ± 0.33 log µM, p < 0.05 / Emax = Ex 9.5 ± 2.9 vs. Ct 17 ± 6.2%, p < 0.05). Exercise did not alter the expression of eNOS and iNOS, but increased the level of p-eNOS.

CONCLUSION

A single resistance exercise session improves endothelial function in hypertensive rats. This response seems to be mediated by increased NO production through eNOS activation.

Correlation between Oxidative Stress, Nutrition, and Cancer Initiation

Inadequate or excessive nutrient consumption leads to oxidative stress, which may disrupt oxidative homeostasis, activate a cascade of molecular pathways, and alter the metabolic status of various tissues. Several foods and consumption patterns have been associated with various cancers and approximately 30-35% of the cancer cases are correlated with overnutrition or malnutrition. However, several contradictory studies are available regarding the association between diet and cancer risk, which remains to be elucidated. Concurrently, oxidative stress is a crucial factor for cancer progression and therapy. Nutritional oxidative stress may be induced by an imbalance between antioxidant defense and pro-oxidant load due to inadequate or excess nutrient supply. Oxidative stress is a physiological state where high levels of reactive oxygen species (ROS) and free radicals are generated. Several signaling pathways associated with carcinogenesis can additionally control ROS generation and regulate ROS downstream mechanisms, which could have potential implications in anticancer research. Cancer initiation may be modulated by the nutrition-mediated elevation in ROS levels, which can stimulate cancer initiation by triggering DNA mutations, damage, and pro-oncogenic signaling. Therefore, in this review, we have provided an overview of the relationship between nutrition, oxidative stress, and cancer initiation, and evaluated the impact of nutrient-mediated regulation of antioxidant capability against cancer therapy.