Effects of short-term endurance training on aortic distensibility in young males

Association between Tai Chi Yuttari Exercise and Longevity and Prevention of Long-Term Care Need: Survival Analysis in Kitakata City, Japan

This study examined whether participation in Tai Chi Yuttari exercise is associated with a delay in the death and new certification for long-term care need of older adults. Individuals who participated in Tai Chi Yuttari exercise classes in 2011-2015 (participation group) were compared with individuals from the Basic Resident Register of Kitakata City (non-participation group). Death and new certification for long-term care need were selected to evaluate the effectiveness of participation in Tai Chi Yuttari exercise classes. The periods from the start date of the observation to each person's date of occurrence of events were calculated. The Kaplan-Meier method and log-rank test were used to compare survival curves between the groups. A total of 105 and 202 individuals in the participation and non-participation groups, respectively, were observed. Survival duration (χ2 = 8.782, p = 0.003) and the period before receiving certification for long-term care (χ2 = 5.354, p = 0.021) were longer in the participation group than in the non-participation group. In the stratified analysis by sex, survival duration was longer in the participation group in men only (χ2 = 7.875, p = 0.005). Participation in Tai Chi Yuttari exercise might be effective in delaying death, especially in men, and new certification for long-term care.

The effect of aerobic exercise on pulse wave velocity in middle-aged and elderly people: A systematic review and meta-analysis of randomized controlled trials

A growing body of research examines the effect of aerobic exercise on pulse wave velocity (PWV) in middle-aged and elderly people, while findings of available studies were conflicting. The aim of this study was to explore the effect of aerobic exercise on PWV in middle-aged and elderly people. Searches were performed in PubMed, Web of Science, and EBSCO databases. Cochrane risk assessment tool was used to evaluate the methodological quality of the included literature. We included studies that satisfied the following criteria: (1) eligible studies should be randomized controlled trials (RCTs); (2) eligible studies should include both an intervention and a control group; (3) eligible studies should use the middle-aged or elderly people as subjects; and (4) eligible studies should use PWV as the outcome measure. From 972 search records initially identified, 11 studies with a total of 12 exercise groups (n = 245) and 11 control groups (n = 239) were eligible for meta-analysis. There was a significant effect of aerobic exercise on reducing PWV in middle-aged and elderly people [weighted mean difference (WMD), –0.75 (95% CI, –1.21 to –0.28), p = 0.002]. Specifically, a higher intensity [vigorous-intensity, –0.74 (–1.34 to –0.14), p = 0.02; moderate-intensity, –0.68 (–1.49 to 0.12), p = 0.10], a younger age [45 years ≤ age < 60 years, –0.57 (–0.78 to –0.37), p < 0.00001; age ≥ 60 years, –0.91 (–2.10 to 0.27), p = 0.13], a better health status [healthy, –1.19 (–2.06 to –0.31), p = 0.008; diseased, –0.32 (–0.64 to –0.01), p = 0.04], and a lower basal body mass index (BMI) [BMI < 25, –1.19 (–2.06 to –0.31), p = 0.008; 25 ≤ BMI < 30, –0.52 (–0.92 to –0.12), p = 0.01; BMI ≥ 30, –0.09 (–0.93 to 0.76), p = 0.84] were associatedwith larger reductions in PWV. Aerobic exercise, especially vigorous-intensity aerobic exercise, contributed to reducing PWV in middle-aged and elderly people. The effect of aerobic exercise on improving PWV was associated with characteristics of the participants. Specifically, a younger age, a better health status, and a lower basal BMI contributed to more significant reductions in PWV.

Venous volume and compliance in the calf and forearm does not change after acute endurance exercise performed at continuous or interval workloads

Short-term endurance exercise training for 6-8 weeks leads to increases in venous volume and compliance in the limbs. However, it is not known whether these venous vascular properties are improved by acute endurance exercise. We examined the effects of acute endurance exercise involving continuous or interval workloads on venous volume and compliance in the exercising (calf) and non-exercising (forearm) limbs. Sixteen healthy young volunteers performed cycling exercise involving a continuous workload of 60% heart rate (HR) reserve or an interval workload of 40% HRreserve and 80% HRreserve, alternating every 2 min, for a total of 32 min each. Before and 60 min after acute cycling exercise, venous volume in the calf and forearm was measured by venous occlusion plethysmography during a cuff-deflation protocol with a venous collecting cuff wrapped to the thigh and upper arm and strain gauges attached to the calf and forearm. The cuff pressure was maintained at 60 mmHg for 8 min and was then deflated to 0 mmHg at a rate of 1 mmHg/s. Venous compliance was calculated as the numerical derivative of the cuff pressure-limb venous volume curve. In both the calf and forearm, the cuff pressure-venous volume curve and the cuff pressure-venous compliance relationship did not differ between before and 60 min after exercise involving continuous or interval workloads. These results suggest that acute exercise does not improve venous volume and compliance in both the exercising and non-exercising limbs.

Differences between Elite Male and Female Badminton Athletes Regarding Heart Rate Variability, Arterial Stiffness, and Aerobic Capacity

Cardiovascular health and aerobic capacity play crucial roles in determining the performance of athletes in the highly competitive sport of badminton. Few studies have directly compared heart rate variability (HRV), arterial stiffness, and aerobic capacity between male and female athletes, especially among badminton athletes. This study investigated sex differences in HRV, arterial stiffness, and aerobic capacity in badminton athletes. Elite badminton athletes were recruited and divided into male (n = 20, 21.0 ± 1.8 years old) and female (n = 16, 21.2 ± 2.3 years old) groups. Both groups performed an incremental treadmill running test for the evaluation of maximal oxygen consumption (V.O2max), anaerobic threshold, and time to exhaustion. They started exercising at a treadmill speed of 2.7 km/h and an inclination of 10% gradient for 3 min, and the speed and inclination were gradually increased every 3 min until they were exhausted or fatigued volitionally. HRV was examined using the Polar heart rate monitor over a period of 5 min at rest in the supine position. Subsequently, the index of arterial stiffness was examined under the same condition. Our results revealed significant differences between the male and female athletes in V.O2max (men: 60.38 ± 8.98 mL/kg/min, women: 48.13 ± 7.72 mL/kg/min, p < 0.05), anaerobic threshold (men: 41.50 ± 7.26 mL/kg/min, women: 32.51 ± 6.19 mL/kg/min, p < 0.05), time to exhaustion (men: 902.15 ± 120.15 s, women: 780.56 ± 67.63 s, p < 0.05), systolic blood pressure (men: 125.27 ± 7.76 mmHg, women: 107.16 ± 11.09 mmHg, p < 0.05), and arterial stiffness index (men: 63.56 ± 12.55, women: 53.83 ± 8.03, p < 0.05). However, no significant differences in HRV measures were observed between the two groups. These findings suggested that the male badminton athletes demonstrated significantly higher aerobic capacity than did the female athletes, but there were no significant differences in HRV measures. The female athletes exhibited superior arterial function, compared with their male counterparts.

The Impact of Fitness Status on Vascular and Baroreceptor Function in Healthy Women and Men

BACKGROUND

Chronic endurance exercise training elicits desirable physiological adaptations in the cardiovascular system. The volume of exercise training required to generate healthy adaptations is unclear. This study assessed the effects of differing exercise training levels on arterial stiffness, compliance, and autonomic function.

METHODS

Eighty healthy adults (38.5 ± 9.7 years; 44% female) defined as endurance-trained (ET, n = 29), normally active (NA, n = 27), or inactive (IN, n = 24) participated. Cardiovascular markers, including hemodynamics, large arterial compliance and small arterial compliance (LAC and SAC), carotid-femoral pulse wave velocity (PWV), and spontaneous baroreceptor sensitivity (BRS) were assessed.

RESULTS

ET showed significantly greater LAC values (21.4 ± 6.5) than NA (16.9 ± 2.5; p = 0.002) and IN (14.7 ± 3.2 mL × mm Hg × 10; p = 0.028). Values for SAC and BRS were significantly higher in ET than IN (p < 0.001 and p = 0.028, respectively), but not NA. Compared to IN, PWV values for ET and NA were significantly lower (p < 0.003). After adjusting for covariates (age, sex, and SBP), significant associations with cardiovascular fitness status were noted for all markers but BRS.

CONCLUSION

Endurance exercise increases LAC likely due to high-volume training; however, lower volumes of physical activity may be sufficient to positively benefit vascular health overall.

THE EFFECTS OF BASKETBALL AND SOCCER TRAINING ON ARTERIAL STIFFNESS

ABSTRACT Objective The purpose of this study was to examine arterial stiffness in elite basketball and soccer athletes by pulse wave velocity. Methods The cohort comprised 35 healthy male volunteers aged 17 to 26 years. All the subjects were either basketball players (n=9), soccer players (n=12) or sedentary controls (n=14). Arterial stiffness was measured by the Pulse Trace System (Micro Medical Ltd., Rochester, UK) and echocardiographic images were taken using a commercially available machine (Vivid 7 GE-Vingmed, Horten, Norway) with a 2.5 MHz transducer. Results The basketball players had significantly higher heights and body weights as compared to both the soccer players and the controls. The aortic elastic properties derived from the echocardiographic measurements did not differ between the groups. The peripheral pulse wave velocity measurements showed significantly lower values both in the basketball and soccer players compared to the controls, whereas the central pulse wave velocity measurement was significantly lower only in the basketball players as compared to the controls. No significant difference was seen between the basketball and soccer players. Conclusions The results of this study show that football and basketball exercises comprised of aerobic, anaerobic, endurance balance-coordination and sport-specific training play a role in reducing arterial stiffness. Level of evidence I; type of study: prognostic study.

The impact of low-intensity blood flow restriction endurance training on aerobic capacity, hemodynamics, and arterial stiffness

BACKGROUND

The aim of this study was to determine the effects of short-term low-intensity blood flow restriction (BFR) endurance training (ET) programs on measures of aerobic capacity, hemodynamics, and arterial stiffness in healthy young males.

METHODS

Thirty-nine healthy young recreationally active males participated in this short-term training study. They were randomly assigned to a high-intensity (HI; N.=11; trained at 60-70% of VO<inf>2</inf> reserve [VO<inf>2</inf>R]), low-intensity (LI; N.=8; trained at 30-40% of VO<inf>2</inf>R), low-intensity with BFR (LI-BFR; N.=10; trained at 30-40% of VO<inf>2</inf>R with BFR) or a non-exercising control group (N.=10). The exercising subjects completed a 6-wk training protocol on a treadmill. Assessment of aerobic capacity (VO<inf>2max</inf>), hemodynamics and arterial stiffness were done before and after training.

RESULTS

Statistical analyses revealed a significant condition main effect (P<0.05) for VO<inf>2max</inf>, indicating significant increase (P<0.05) in VO<inf>2max</inf> in LI-BFR group compared to control. There were no significant changes for resting heart rate (RHR), systolic blood pressure (SBP), diastolic blood pressure (DBP), carotid-radial pulse wave velocity (PWV), and carotid-femoral PWV (P>0.05). However, femoral-tibial PWV decreased significantly (P<0.05) from baseline to post-training.

CONCLUSIONS

The results indicate that the application of BFR during ET may cause faster and/or greater adaptations in one or more physiological systems resulting in improved cardiorespiratory fitness.

Cardiorespiratory fitness is associated with increased middle cerebral arterial compliance and decreased cerebral blood flow in young healthy adults: A pulsed ASL MRI study

Cardiorespiratory fitness is thought to have beneficial effects on systemic vascular health, in part, by decreasing arterial stiffness. However, in the absence of non-invasive methods, it remains unknown whether this effect extends to the cerebrovasculature. The present study uses a novel pulsed arterial spin labelling (pASL) technique to explore the relationship between cardiorespiratory fitness and arterial compliance of the middle cerebral arteries (MCAC). Other markers of cerebrovascular health, including resting cerebral blood flow (CBF) and cerebrovascular reactivity to CO2 (CVRCO2) were also investigated. Eleven healthy males aged 21 ± 2 years with varying levels of cardiorespiratory fitness (maximal oxygen uptake (V · O2MAX) 38-76 ml/min/kg) underwent MRI scanning at 3 Tesla. Higher V · O2MAX was associated with greater MCAC (R2 = 0.64, p < 0.01) and lower resting grey matter CBF (R2 = 0.75, p < 0.01). However, V · O2MAX was not predictive of global grey matter BOLD-based CVR (R2 = 0.47, p = 0.17) or CBF-based CVR (R2 = 0.19, p = 0.21). The current experiment builds upon the established benefits of exercise on arterial compliance in the systemic vasculature, by showing that increased cardiorespiratory fitness is associated with greater cerebral arterial compliance in early adulthood.

Dose of Alcohol From Beer Required for Acute Reduction in Arterial Stiffness

Acute beer or alcohol ingestion reduces arterial stiffness, but the dose required to reduce arterial stiffness is unclear. Therefore, this study aimed to determine the acute effects of ingesting various amounts of beer on arterial stiffness in healthy men. Nine men (20–22 years) participated, in eight trials in random order on different days. The participants each consumed 25, 50, 100, or 200 mL of alcohol-free beer (AFB25, AFB50, AFB100, and AFB200) or regular beer (B25, B50, B100, and B200), and were monitored for 60 min thereafter. Arterial stiffness did not significantly change among all AFB and B25. However, B50, B100, and B200 caused a significant decrease in arterial stiffness for approximately 30–60 min: heart-brachial pulse wave velocity (B50: −4.5 ± 2.4%; B100: −3.4 ± 1.3%; B200: −8.1 ± 2.6%); brachial-ankle pulse wave velocity (B50: −0.6 ± 2.0%; B100: −3.3 ± 1.1%; B200: −9.3 ± 3.0%); heart-ankle pulse wave velocity (B50: −3.7 ± 0.3%; B100: −3.3 ± 0.9%; B200: −8.1 ± 2.7%); and cardio-ankle vascular index (B50: −4.6 ± 1.3%; B100: −5.6 ± 0.8%; B200: −10.3 ± 3.1%). Positive control alcoholic beverages reduced arterial stiffness, and these reductions did not significantly differ regardless of the type of beverage. Our data show that consuming about 50 mL of beer can start to reduce arterial stiffness, and that the reduced arterial stiffness is mainly attributable to the alcohol in beer.

The influence of habitual endurance exercise on carotid artery strain and strain rate in young and middle-aged men

NEW FINDINGS

What is the central question of this study? Carotid artery peak circumferential strain (PCS) and strain rate attenuate with age, but appear to be modulated by cardiorespiratory fitness status in young males. However, the relationship between habitual endurance exercise (running) and these parameters has not been studied in young and middle-aged men. What is the main finding and its importance? Young and middle-aged runners exhibited elevated PCS and systolic strain rate (S-SR) compared with non-runners, but habitual running did not influence diastolic strain rate (D-SR). Habitual exercise is associated with comparable improvements in carotid strain parameters in young and middle-aged men, but the age-related decline in PCS and S-SR might be more amenable to habitual endurance exercise than D-SR.

ABSTRACT

Central arterial stiffness is an independent predictor of cardiovascular risk that can be modified by exercise training. However, conventional local measures of carotid artery stiffness display conflicting responses to habitual endurance exercise in young and older adults. Two-dimensional (2D)-Strain imaging of the common carotid artery (CCA) quantifies circumferential deformation (strain) of the arterial wall across the cardiac cycle, which is more sensitive at detecting age-related alterations in CCA stiffness than conventional methods. Therefore, the study was designed to examine the relationship between habitual endurance exercise (running) and CCA 2D-Strain parameters in young and middle-aged men. Short-axis ultrasound images of the CCA were obtained from 13 young non-runners [23 years of age (95% confidence interval: 21, 26 years of age)], 19 young runners [24 (22, 26) years of age], 13 middle-aged non-runners [54 (52, 56) years of age] and 19 middle-aged runners [56 (54, 58) years of age]. Images were analysed for peak circumferential strain (PCS; magnitude of deformation) and systolic and diastolic strain rates (S-SR and D-SR; deformation velocity), and group differences were examined via two-way ANOVA. PCS, S-SR and D-SR were attenuated in middle-aged men compared with young men (all P ≤ 0.001). PCS and S-SR were elevated in young and middle-aged runners when compared with non-runners (P = 0.002 and P = 0.009, respectively), but no age × training status interaction was observed. In contrast, there was no influence of habitual running on D-SR. Habitual exercise is associated with comparable improvements in CCA 2D-Strain parameters in young and middle-aged men, but the age-related decline in PCS and S-SR might be more amenable to habitual endurance exercise than D-SR.

Effects of different intensities and durations of aerobic exercise training on arterial stiffness

[Purpose] In the present study, we investigated the effects of regular aerobic training with different intensities and durations on new indices of arterial stiffness measured via an upper-arm oscillometric device. [Participants and Methods] We gathered data from 41 middle-aged and older people (age 65.0 ± 11.7 years). Participants were randomly divided into five groups: (1) 15 minutes of low intensity aerobic training (n=10); (2) 30 minutes of low intensity training (n=7); (3) 15 minutes of moderate-intensity training (n=9); (4) 30 minutes of moderate-intensity training (n=8); and (5) a non-training group (n=7). Training was conducted for 8 weeks, three times per week. Arterial pulse wave index, arterial pressure-volume index, brachial-ankle and heart-brachial pulse wave velocity, cardio-ankle vascular index, brachial and ankle blood pressure, heart rate, and peak oxygen uptake were measured before and after the intervention. [Results] All indicators of arterial stiffness and brachial and ankle blood pressure in the exercise groups were significantly lower after versus before the intervention. Peak oxygen uptake did not differ before versus after the intervention. [Conclusion] The present findings indicate that regular aerobic exercise may be important in reducing arterial stiffness regardless of the intensity or duration of aerobic exercise.

Effect of short-term endurance training on venous compliance in the calf and forearm differs between continuous and interval exercise in humans

We examined whether the effect of short-term endurance exercise training on venous compliance in the calf and forearm differed between continuous and interval workloads. Young healthy volunteers (10 women and 16 men) were randomly assigned to continuous (C-TRA; n = 8) and interval (I-TRA; n = 9) exercise training groups, and a control group (n = 9). Subjects in the C-TRA group performed a continuous cycling exercise at 60% of heart rate reserve (HRR), and subjects in the I-TRA group performed a cycling exercise consisting of alternating 2-min intervals at 40% HRR and 80% HRR. Training programs were performed for 40 min/day, 3 days/week for 8 weeks. Before and after training, limb volume in the calf and forearm was measured with subjects in the supine position by venous occlusion plethysmography using a venous collecting cuff placed around the thigh and upper arm. Cuff pressure was held at 60 mmHg for 8 min and then decreased to 0 mmHg at a rate of 1 mmHg/s. Venous compliance was calculated as the numerical derivative of the cuff pressure-limb volume curve. Calf venous compliance was increased after I-TRA, but not C-TRA. Forearm venous compliance was unchanged after C-TRA or I-TRA. These results suggest that the adaptation of venous compliance in response to endurance training for 8 week may occur in interval but not continuous exercise bouts and may be specific to the exercising limb.

Arterial adaptations in athletes of dynamic and static sports disciplines - a pilot study

BACKGROUND

Structural and functional arterial adaptations with regard to the type and level of training in young athletes are understudied. Our research aimed at evaluating them in two types of exercise (dynamic and static) and two levels of engagement (high and recreational).

METHODS

A total of 76 volunteers formed five groups. Group A included 17 high-level dynamic sports athletes 30·9 ± 6·4 years old, group B 14 recreational ones aged 28·7 ± 6·2 years, group C 15 high-level static sports athletes 26·4 ± 3·9 years old and group D 16 recreational ones, aged 25·8 ± 4·8 years. Fourteen sedentary men 30 ± 3·8 years old formed control group E. Structural indices of left cardiac chambers and thoracic aorta were echographically obtained, as well as common carotid intima-media thickness (cIMT). Furthermore, applanation tonometry was conducted, at rest and during a handgrip strength test, for the acquisition of central arterial pressure parameters, carotid-femoral pulse wave velocity (cfPWV) and total arterial compliance (C_τ ).

RESULTS

No significant differences in structural arterial markers were observed. However, group A obtained the highest handgrip central systolic pressure values (13·1% compared to group D, P<0·05). Resting cfPWV was lower in group B by 13·8% (P<0·05) than C and by 16·7% (P<0·01) than E, whereas C_τ was higher in group Β by 33·3% than C (P<0·05) and by 40·9% than E (P<0·01).

CONCLUSION

Functional arterial exercise-induced adaptations become apparent at an early age, without being in conjunction with structural ones. Recreational dynamic exercise results in the most favourable arterial characteristics.

Vascular characteristics in young women-Effect of extensive endurance training or a sedentary lifestyle

AIM

To explore whether high-level endurance training in early age has an influence on the arterial wall properties in young women.

METHODS

Forty-seven athletes (ATH) and 52 controls (CTR), all 17-25 years of age, were further divided into runners (RUN), whole-body endurance athletes (WBA), sedentary controls (SC) and normally active controls (AC). Two-dimensional ultrasound scanning of the carotid arteries was conducted to determine local common carotid artery (CCA) geometry and wall distensibility. Pulse waves were recorded with a tonometer to determine regional pulse wave velocity (PWV) and pulse pressure waveform.

RESULTS

Carotid-radial PWV was lower in WBA than in RUN (P < .05), indicating higher arterial distensibility along the arm. Mean arterial pressure was lower in ATH than in CTR and in RUN than in WBA (P < .05). Synthesized aortic augmentation index (AI@75) was lower among ATH than among CTR (-12.8 ± 1.6 vs -2.6 ± 1.2%, P < .001) and in WBA than in RUN (-16.4 ± 2.5 vs -10.7 ± 2.0%, P < .05), suggesting a diminished return of reflection waves to the aorta during systole. Carotid-femoral PWV and intima-media thickness (IMT), lumen diameter and radial distensibility of the CCA were similar in ATH and CTR.

CONCLUSION

Elastic artery distensibility and carotid artery IMT are not different in young women with extensive endurance training over several years and in those with sedentary lifestyle. On the other hand, our data suggest that long-term endurance training is associated with potentially favourable peripheral artery adaptation, especially in sports where upper body work is added. This adaptation, if persisting later in life, could contribute to lower cardiovascular risk.

Exercise training in patients with pulmonary and systemic hypertension: A unique therapy for two different diseases

Pulmonary hypertension is a potentially life-threatening condition. Given its evolving definition, the incidence and prevalence of the disease is difficult to define, but registries suggest an increased global awareness. The management of patients with pulmonary arterial hypertension is highly specialised and requires multi-disciplinary input from a range of healthcare professionals, including cardiologists, respiratory physicians, rheumatologists, rehabilitation physicians and cardio-pulmonary physiotherapists. Historically, exercise training in pulmonary hypertension has not been recommended because of safety concerns. However, an increasing number of studies have demonstrated the benefit of exercise training on exercise capacity, peak oxygen consumption and quality of life. Systemic hypertension is one of the most important risk factors for cardiovascular disease, and has been ranked as the leading cause for death and disability worldwide: therefore, adequate control of blood pressure is important for public health. Lowering of blood pressure and prevention of hypertension is in first instance preferable by lifestyle changes. These include weight loss, moderation of alcohol intake, a diet with increased fresh fruit and vegetables, reduced saturated fat, reduced salt intake, reduced stress, and, finally, increased physical activity. With regard to the latter, former guidelines predominantly recommended aerobic exercises such as walking, jogging, and cycling for lowering blood pressure. The main focus of this narrative overview paper is to briefly examine and summarize the benefit of exercise training in patients with pulmonary and systemic hypertension, suggest mechanisms by which exercise may improve symptoms and function and provide evidence-based recommendations regarding the frequency and intensity of exercise in these patients.

Effect of Exercise on Arterial Stiffness: Is There a Ceiling Effect?

BACKGROUND

Whether arterial stiffness (AS) can be improved by regular exercise in healthy individuals remains equivocal according to cross-sectional and longitudinal studies assessing arterial properties at discrete time points. The purpose of the present study was to pinpoint the time course of training-induced adaptations in central AS.

METHODS

Aorta characteristic impedance (Zc) and carotid distensibility (CD) were determined with ultrasonography prior to (week 0) and across 8 weeks (weeks 2, 4, and 8) of supervised endurance training (ET) (3 × 60 minutes cycle ergometry sessions per week), in 9 previously untrained healthy normotensive adults (27 ± 4 years) with no history of cardiovascular disease. Exercise capacity was assessed by maximal oxygen consumption (VO2max) elicited by incremental ergometry.

RESULTS

VO2max increased throughout the ET intervention (+12% from week 0 to week 8, P < 0.001, P for linear trend <0.001). Systolic blood pressure rose with ET (+7% from week 0 to week 8, P = 0.019, P for linear trend <0.001). Aorta Zc augmented from week 0 to week 8 of ET in all individuals (+38%, P = 0.003, P for linear trend = 0.002). CD did not significantly differ among time points (P = 0.196) although a linear decreasing trend was detected (P = 0.016).

CONCLUSIONS

Central AS augments during a conventional ET intervention that effectively enhances aerobic exercise capacity in young individuals. This suggests that normal, healthy elastic arteries are not amendable to improvement unless impairment is present.

Acute effects of incremental exercise on central hemodynamics in young basketball athletes

Acute effects of competitive sports on central hemodynamics are controversial. This study was aimed to evaluate acute effects of incremental exercise on central hemodynamics in young basketball athletes during 1-hour recovery. Fifteen young basketball athletes and fifteen controls underwent the acquisition of peripheral and central blood pressure before exercise and at 0, 5, 10, 15, 20, 30, 40, 50, 60 min after incremental exercise. The incremental exercise was performed by Bruce test. Aortic systolic pressure (ASP), sub-endocardial viability ratio and stroke volume were significantly higher in athletes at all time points measured before and after exercise (P<;0.05). Heart rate and ejection duration were significantly lower in athletes (P<;0.01 for all). Augmentation index (AIx) was higher in athletes than that in controls at rest. AIx significantly reduced in athletes at 0 min after exercise (P<;0.01), but not in controls. Both Cardiac output and total peripheral resistance significantly changed in athletes at 0 min after exercise (P<;0.01). Cardiac functions to incremental exercise at all time points in basketball athletes are stronger than those in controls. However, potential mechanism of vascular functions should be further explored because basketball athletes have higher ASP and AIx than those in controls.

Acute Effect of Static Stretching Exercise on Arterial Stiffness in Healthy Young Adults

OBJECTIVE

Habitual stretching exercise increases carotid arterial compliance, and acute stretching exercise increases arterial compliance in patients with myocardial infarction. However, it is not known whether this arterial adaptation is sustained after exercise. The aim of this study was to examine the effect of a single bout of stretching exercise on the time course of systemic, central, and peripheral arterial stiffness in healthy young subjects.

DESIGN

Twenty-six healthy young men performed static stretching exercise involving the entire body (trunk, upper limb, and lower limb) for 40 mins. Pulse-wave velocity (PWV; an index of arterial stiffness), blood pressure, and heart rate were measured before and 0, 15, 30, and 60 mins after stretching exercise.

RESULTS

Femoral-ankle PWV and brachial-ankle PWV were reduced relative to baseline 15 and 30 mins after acute stretching (P < 0.05); however, these arterial responses were not sustained for longer periods, and both PWV values returned to the baseline levels within 60 mins. By contrast, carotid-femoral PWV was unchanged.

CONCLUSION

These results suggest that chronic and sufficient repetition of muscle stretch stimulation may result in chronic high arterial compliance, although a single bout of stretch exercise acutely affects arterial compliance.

Changes in brachial artery endothelial function and resting diameter with moderate-intensity continuous but not sprint interval training in sedentary men

Moderate-intensity continuous training (MICT) improves peripheral artery function in healthy adults, a phenomenon that reverses as continued training induces structural remodeling. Sprint interval training (SIT) elicits physiological adaptations similar to MICT, despite a lower exercise volume and time commitment; however, its effect on peripheral artery function and structure is largely unexplored. We compared peripheral artery responses to 12 wk of MICT and SIT in sedentary, healthy men (age = 27 ± 8 yr). Participants performed MICT (45 min of cycling at 70% peak heart rate; n = 10) or SIT (3 × 20-s "all out" cycling sprints with 2 min of recovery; n = 9), and responses were compared with a nontraining control group (CTL, n = 6). Allometrically scaled brachial flow-mediated dilation (FMD) increased 2.2% after 6 wk of MICT and returned to baseline levels by 12 wk, but did not change in SIT or CTL (group × time interaction, P = 0.04). Brachial artery diameter increased after 6 and 12 wk (main effect, P = 0.03), with the largest increases observed in MICT. Neither training protocol affected popliteal relative FMD and diameter, or central and lower limb arterial stiffness (carotid distensibility, central and leg pulse wave velocity) (P > 0.05 for all). Whereas earlier and more frequent measurements are needed to establish the potential presence and time course of arterial responses to low-volume SIT, our findings suggest that MICT was superior to the intense, but brief and intermittent SIT stimulus at inducing brachial artery responses in healthy men.NEW & NOTEWORTHY We compared the effects of 12 wk of moderate-intensity continuous training (MICT) and sprint interval training (SIT) on peripheral artery endothelial function and diameter, and central and lower limb stiffness in sedentary, healthy men. Whereas neither training program affected the popliteal artery or stiffness indexes, we observed changes in brachial artery function and diameter with MICT but not SIT. Brachial artery responses to SIT may follow a different time course or may not occur at all.

Acute effect of stretching one leg on regional arterial stiffness in young men

PURPOSE

Our previous study demonstrated that a single bout of stretching exercises acutely reduced arterial stiffness. We hypothesized that this acute vascular response is due to regional mechanical stimulation of the peripheral arteries. To test this hypothesis, we examined the effect of a single bout of passive one leg stretching on arterial stiffness, comparing the stretched and the non-stretched leg in the same subject.

METHODS

Twenty-five healthy young men (20.9 ± 0.3 years, 172.5 ± 1.4 cm, 64.1 ± 1.2 kg) volunteered for the study. Subjects underwent a passive calf stretching on one leg (six repetitions of 30-s static stretch with a 10-s recovery). Pulse wave velocity (PWV, an index of arterial stiffness), blood pressure (BP), and heart rate (HR) were measured before and immediately, 15, and 30 min after the stretching.

RESULTS

Femoral-ankle PWV (faPWV) in the stretched leg was significantly decreased from baseline (835.0 ± 15.9 cm/s) to immediately (802.9 ± 16.8 cm/s, P < 0.01) and 15 min (810.5 ± 16.0 cm/s, P < 0.01) after the stretching, despite no changes in systolic and diastolic BP, or HR. However, faPWV in the non-stretched leg was not significantly altered at any time. Brachial-ankle PWV (baPWV) also showed similar responses with faPWV, but this response was not significant. Additionally, the passive stretching did not alter carotid-femoral PWV (cfPWV).

CONCLUSIONS

These results suggest that mechanical stimulation to peripheral arteries as induced by static passive stretch may modulate arterial wall properties directly, rather than resulting in a systemic effect.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Arterial stiffness in young adult swimmers

PURPOSE

Habitual Aerobic exercise reduces arterial stiffness, but effects of habitual swimming on arterial stiffness are not yet fully understood. Swimming can also increase systolic blood pressure (BP) in normotensive individuals. Accordingly, this cross-sectional study aimed to investigate arterial stiffness in young adult swimmers after considering the influence of BP.

METHODS

Participants comprised 41 men (18-21 years), including 15 untrained controls (C), 11 competitive cyclists (aerobic-trained athletes; A), and 15 competitive swimmers (S). Arterial stiffness was assessed by brachial-ankle pulse-wave velocity (baPWV), heart-ankle pulse-wave velocity (haPWV), and cardio-ankle vascular index (CAVI). CAVI is the measurement of arterial stiffness that is theoretically adjusted by BP.

RESULTS

Although physical characteristics and handgrip strength did not differ between groups, peak oxygen uptake was significantly greater in A and S than in C. A tendency towards higher systolic BP and a significantly higher pulse pressure were found in S as compared to C and A. Most importantly, baPWV was significantly lower in A than in C or S, and no significant difference in baPWV was observed between C and S (C, 1027 ± 25; A, 852 ± 23; S, 1032 ± 24 cm/s). No significant difference in haPWV was observed. However, CAVI was significantly lower in A and S than in C, and did not differ significantly between A and S (C, 5.8 ± 0.2; A, 5.1 ± 0.2; S, 5.3 ± 0.2 unit).

CONCLUSION

These findings indicate that arterial stiffness in young adult swimmers is lower than in age-matched sedentary controls and similar to land-based aerobic-exercise individuals, after considering the influences of BP.

Effects of habitual aerobic exercise on the relationship between intramyocellular or extramyocellular lipid content and arterial stiffness

The accumulation of intramyocellular lipid (IMCL) and extramyocellular lipid (EMCL) is associated with arterial stiffness in middle-aged and older adults. Habitual aerobic exercise induces the improvement of arterial stiffness with reduction in fat accumulation. However, the relationship between aerobic exercise-induced changes in muscular lipids and arterial stiffness remains unclear. The purpose of this study was to investigate whether habitual aerobic exercise-induced changes in IMCL and EMCL content would lead to an improvement of arterial stiffness. First, in a cross-sectional study, we investigated whether cardiorespiratory fitness level affects the association between IMCL or EMCL content and arterial stiffness in 60 middle-aged and older subjects (61.0±1.3 years). Second, in an intervention study, we examined whether aerobic exercise training-induced changes in IMCL and EMCL content are associated with a reduction in arterial stiffness in 18 middle-aged and older subjects (67.0±1.7 years). In the cross-sectional study, IMCL content was negatively correlated with brachial-ankle pulse wave velocity (baPWV) (r=-0.47, P<0.05), whereas EMCL content was positively correlated with baPWV (r=0.48, P<0.05) in the low-fitness group, but was not correlated in the high-fitness group. Furthermore, 8-week aerobic exercise training in older adults increased IMCL content and reduced EMCL content. The training-induced change in baPWV was negatively correlated with training-induced changes in IMCL but was positively correlated with training-induced changes in EMCL. These findings suggest that aerobic exercise training-induced changes in IMCL and EMCL content may be related to a reduction in arterial stiffness in middle-aged and older adults.

Cardiovascular risk, chronic obstructive pulmonary disease and pulmonary rehabilitation: Can we learn from cardiac rehabilitation?

Patients with chronic obstructive pulmonary disease (COPD) who participate in pulmonary rehabilitation (PR) often have concomitant cardiovascular disease (CVD), which is a frequently undiagnosed and undertreated comorbidity. CVD contributes to the burden of the disease and is associated with an increased risk for hospitalizations and mortality. Optimizing the diagnosis and management of cardiovascular risk and disease should be considered as part of the holistic approach of PR. In addition, we need to consider similarities and differences in cardiac and PR programs, in order to improve personalized care in patients with both diseases. The current review addresses the burden of CVD in COPD patients who participate in PR, how CVD and its risk factors affect PR and should be managed during PR, and extends on what we can learn of the organization of cardiac rehabilitation programs.

Systolic blood pressure response after high-intensity interval exercise is independently related to decreased small arterial elasticity in normotensive African American women

Aerobic exercise transiently lowers blood pressure. However, limited research has concurrently evaluated blood pressure and small arterial elasticity (SAE), an index of endothelial function, among African American (AA) and European American (EA) women the morning after (i.e., ≈22 h later) acute bouts of moderate-intensity continuous (MIC) and high-intensity interval (HII) exercise matched for total work. Because of greater gradients of shear stress, it was hypothesized that HII exercise would elicit a greater reduction in systolic blood pressure (SBP) compared to MIC exercise. After baseline, 22 AA and EA women initiated aerobic exercise training 3 times/week. Beginning at week 8, three follow-up assessments were conducted over the next 8 weeks at random to measure resting blood pressure and SAE. In total all participants completed 16 weeks of training. Follow-up evaluations were made: (i) in the trained state (TS; 8-16 weeks of aerobic training); (ii) ≈22 h after an acute bout of MIC exercise; and (iii) ≈22 h after an acute bout of HII exercise. Among AAs, the acute bout of HII exercise incited a significant increase in SBP (mm Hg) (TS, 121 ± 14 versus HII, 128 ± 14; p = 0.01) whereas responses (TS, 116 ± 12 versus HII, 113 ± 9; p = 0.34) did not differ in EAs. After adjusting for race, changes in SAE were associated (partial r = -0.533; p = 0.01) with changes in SBP following HII exercise. These data demonstrate an acute, unaccustomed bout of HII exercise produces physiological perturbations resulting in a significant increase in SBP that are independently associated with decreased SAE among AA women, but not EA women.

Influence of detraining on temporal changes in arterial stiffness in endurance athletes: a prospective study

[Purpose] We examined the effects of detraining on temporal changes in arterial stiffness in endurance athletes. [Subjects] Eighteen female university athletes requiring high endurance exercise capabilities were classified into 2 groups: 10 retired players (detraining group) and 8 active players (training group). [Methods] Brachial-ankle pulse wave velocity, an index of arterial stiffness, was measured a total of 6 times: immediately before retirement of the detraining group and at 1, 2, 3, 6, and 12 months after retirement. [Results] Brachial-ankle pulse wave velocity was measured in the training group at the same 6 points to allow comparison with the detraining group. The brachial-ankle pulse wave velocity in the detraining group increased significantly at 3 and 12 months as compared with that at 0 months and showed a significant increase at 12 months compared with that at 1 month. Moreover, the brachial-ankle pulse wave velocity in the detraining group was significantly higher at 3, 6, and 12 months than in the training group. [Conclusion] These results revealed that detraining may result in increased arterial stiffness from 3 months onward in endurance athletes.

Objectively measured physical activity and sedentary-time are associated with arterial stiffness in Brazilian young adults

OBJECTIVE

To examine the associations between objectively measured physical activity and sedentary time with pulse wave velocity (PWV) in Brazilian young adults.

METHODS

Cross-sectional analysis with participants of the 1982 Pelotas (Brazil) Birth Cohort who were followed-up from birth to 30 years of age. Overall physical activity (PA) assessed as the average acceleration (mg), time spent in moderate-to-vigorous physical activity (MVPA - min/day) and sedentary time (min/day) were calculated from acceleration data. Carotid-femoral PWV (m/s) was assessed using a portable ultrasound. Systolic and diastolic blood pressure (SBP/DBP), waist circumference (WC) and body mass index (BMI) were analyzed as possible mediators. Multiple linear regression and g-computation formula were used in the analyses.

RESULTS

Complete data were available for 1241 individuals. PWV was significantly lower in the two highest quartiles of overall PA (0.26 m/s) compared with the lowest quartile. Participants in the highest quartile of sedentary time had 0.39 m/s higher PWV (95%CI: 0.20; 0.57) than those in the lowest quartile. Individuals achieving ≥30 min/day in MVPA had lower PWV (β = -0.35; 95%CI: -0.56; -0.14). Mutually adjusted analyses between MVPA and sedentary time and PWV changed the coefficients, although results from sedentary time remained more consistent. WC captured 44% of the association between MVPA and PWV. DBP explained 46% of the association between acceleration and PWV.

CONCLUSIONS

Physical activity was inversely related to PWV in young adults, whereas sedentary time was positively associated. Such associations were only partially mediated by WC and DBP.

Athletic differences in the characteristics of the photoplethysmographic pulse shape: effect of maximal oxygen uptake and maximal muscular voluntary contraction

This study aimed to investigate the athletic differences in the characteristics of the photoplethysmographic (PPG) pulse shape. 304 athletes were enrolled and divided into three subgroups according to a typical sport classification in terms of the maximal oxygen uptake (MaxO₂_low, MaxO₂_middle and MaxO₂_high groups) or the maximal muscular voluntary contraction (MMVC_low, MMVC_middle, and MMVC_high groups). Finger PPG pulses were digitally recorded and then normalized to derive the pulse area, pulse peak time T_p, dicrotic notch time T_n, and pulse reflection index (RI). The four parameters were finally compared between the three subgroups categorized by MaxO₂ or by MMVC. In conclusion, it has been demonstrated by quantifying the characteristics of the PPG pulses in different athletes that MaxO₂, but not MMVC, had significant effect on the arterial properties.

Impact of American-style football participation on vascular function

Although hypertension is common in American-style football (ASF) players, the presence of concomitant vascular dysfunction has not been previously characterized. We sought to examine the impact of ASF participation on arterial stiffness and to compare metrics of arterial function between collegiate ASF participants and nonathletic collegiate controls. Newly matriculated collegiate athletes were studied longitudinally during a single season of ASF participation and were then compared with healthy undergraduate controls. Arterial stiffness was characterized using applanation tonometry (SphygmoCor). ASF participants (n = 32, 18.4 ± 0.5 years) were evenly comprised of Caucasians (n = 14, 44%) and African-Americans (n = 18, 56%). A single season of ASF participation led to an increase in central aortic pulse pressure (27 ± 4 vs 34 ± 8 mm Hg, p <0.001). Relative to controls (n = 47), pulse wave velocity was increased in ASF participants (5.6 ± 0.7 vs 6.2 ± 0.9 m/s, p = 0.002). After adjusting for height, weight, body mass index, systolic blood pressure, and diastolic blood pressure, ASF participation was independently predictive of increased pulse wave velocity (β = 0.33, p = 0.04). In conclusion, ASF participation leads to changes in central hemodynamics and increased arterial stiffness.

The Role of Multimodality Cardiac Imaging for the Assessment of Sports Eligibility in Patients with Bicuspid Aortic Valve

Bicuspid aortic valve (BAV) cannot be considered an innocent finding, but it is not necessarily a life-threatening condition. Athletes with BAV should undergo a thorough staging of the valve anatomy, taking into consideration hemodynamic factors, as well as aortic diameters and looking for other associated significant cardiovascular anomalies by use of a multimodality cardiac imaging approach. Furthermore an accurate follow-up is mandatory with serial cardiological controls in those allowed to continue sports.

Effect of aerobic exercise training on arterial stiffness in obese populations : a systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

Controversy exists as to whether aerobic exercise training decreases arterial stiffness in obese subjects. The aim of this study was to systematically review and quantify the effect of aerobic exercise training on arterial stiffness in obese populations.

METHODS

MEDLINE, Cochrane, Scopus, and Web of Science were searched up until May 2013 for trials assessing the effect of aerobic training interventions lasting 8 weeks or more on arterial stiffness in obese populations (body mass index ≥30 kg/m(2)). Standardized mean difference (SMD) in arterial stiffness parameters (augmentation index, β-stiffness, distensibility, pulse wave velocity, arterial waveforms) was calculated using a random-effects model. Subgroup and meta-regression analyses were used to study potential moderating factors.

RESULTS

Eight trials, comprising a total of 235 subjects with an age range of 49-70 years, met the inclusion criteria. Arterial stiffness was not significantly reduced by aerobic training (SMD -0.17; 95 % confidence interval (CI) -0.39, 0.06, P = 0.14). Similarly, post-intervention arterial stiffness was similar between the aerobic-trained and control obese groups (SMD 0.02; 95 % CI -0.28, 0.32, P = 0.88). Neither heterogeneity nor publication bias were detected in these analyses. In subgroup analyses, arterial stiffness was significantly reduced in aerobic-trained subgroups having below median values in post- minus pre-intervention systolic blood pressure (SBP) (P < 0.01), exercise intensity rating score (P < 0.01), and methodological quality score (P < 0.01). Equivalent results were obtained in meta-regression analyses.

CONCLUSION

Based on current published trials, arterial stiffness is generally not reduced in middle-aged and older obese populations in response to aerobic training. However, in studies using low-intensity aerobic training and yielding a decrease in SBP, arterial stiffness may decrease. Long-term studies are needed to assess the prognostic value of these findings.

Effect of combined aerobic and resistance training versus aerobic training on arterial stiffness

BACKGROUND

While aerobic exercise training may decrease arterial stiffness, the impact of combined aerobic and resistance training is unclear. Therefore, the aim of this study was to systematically review and quantify the effect of combined aerobic and resistance training on arterial stiffness, as determined by arterial pulse wave velocity (PWV), and compare it with aerobic training.

METHODS

MEDLINE, EMBASE and Web of Science were searched through November 2013 for randomized controlled trials evaluating the effect of aerobic or combined aerobic and resistance training on PWV. A meta-analysis was performed to determine the standardized mean difference (SMD) in PWV between exercise and control groups. Subgroup analyses were used to study potential moderating factors.

RESULTS

Twenty-one randomized controlled trials comparing exercise and control groups (overall n=752), met the inclusion criteria. After data pooling, PWV was decreased in aerobic trained groups compared with controls (10 trials, SMD=-0.52, 95% CI= -0.76, -0.27; P<0.0001) but did not reach statistical significance in combined trained groups compared with controls (11 trials, SMD=-0.23, 95% CI=-0.50, 0.04; P=0.10). The effect in aerobic trained groups did not differ compared with combined trained groups (P=0.12). In addition, aerobic training resulted in significantly lower SMD in PWV compared with combined training in interventions including a higher volume of aerobic training or assessing carotid-femoral PWV.

CONCLUSIONS

These data suggest that combined aerobic and resistance training interventions may have reduced beneficial effects on arterial stiffness compared with control interventions, but do not appear to differ significantly with aerobic training alone.

Effects of exercise training on systo-diastolic ventricular dysfunction in patients with hypertension: an echocardiographic study with tissue velocity and strain imaging evaluation

There is a lack of detailed data regarding the effect of exercise training in pharmacologically treated hypertensive patients. Therefore, the aim of this study was to evaluate the effects of exercise training on left and right ventricular morphologic and functional parameters by means of conventional echocardiography and sensitive new echocardiographic techniques including tissue Doppler velocity and strain imaging, that were performed in pharmacologically treated hypertensive patients at baseline and at the end of a specific exercise training protocol for primary prevention of cardiovascular disease. We selected 116 pharmacologically treated hypertensive patients who completed the exercise training protocol. All patients underwent a clinical history and examination; transthoracic echocardiography and exercise testing were performed at baseline and at the end of the exercise training protocol. Conventional echocardiography revealed a mild degree of diastolic dysfunction without significant differences or variations from baseline to the end of the exercise training protocol. In contrast, tissue Doppler velocity and strain imaging measurements demonstrated and highlighted the positive influence of exercise training: for both left and right ventricle myocardial early peak diastolic velocities (Em), the ratio of myocardial early-late peak diastolic velocity (Em/Am), myocardial peak systolic velocities (Sm) and peak strain and strain rate values significantly increased at the end of the exercise training protocol, suggesting a relationship between exercise capacity and both left and right ventricular systo-diastolic function. Our study, by means of newer more sensitive echocardiographic techniques, clearly demonstrated the positive impact of exercise training on both left and right ventricular systo-diastolic function, in terms of adjunctive subclinical improvement, in pharmacologically treated hypertensive patients.

The impact of aerobic exercise training on arterial stiffness in pre- and hypertensive subjects: a systematic review and meta-analysis

BACKGROUND

Debate concerning aerobic exercise decreasing arterial stiffness in pre- and hypertensive individuals still exists. We sought to systematically review and quantify the effect of aerobic exercise training on arterial stiffness in pre- and hypertensive subjects.

METHODS

MEDLINE, Cochrane, Scopus and Web of Science were searched up until August 2013 for trials assessing the effect of aerobic exercise interventions lasting 4 or more weeks on arterial stiffness in (pre)hypertensive subjects. Standardized mean difference (SMD) in arterial stiffness parameters (PWV, B-stiffness, Compliance, AIx) was calculated using a random-effects model. Subgroup and meta-regression analyses were used to study potential moderating factors.

RESULTS

Fourteen trials comprising a total of 472 (pre)hypertensive subjects met the inclusion criteria. Arterial stiffness was not significantly reduced by aerobic training in (pre)hypertensive subjects (14 trials, SMD=-0.19; P=.06). Likewise, post-intervention arterial stiffness was similar between the aerobic exercise-trained and control (pre)hypertensive subjects (8 trials, SMD=-0.10; P=.43). Neither heterogeneity nor publication bias was detected in either of these analyses. In the subgroup analyses, arterial stiffness was significantly reduced in aerobic exercise-trained (pre)hypertensive subgroups below the median value in post minus pre-intervention systolic blood pressure (SBP) (SMD=-0.38, P=.04) and in subgroups above the median value in the duration of the intervention (SMD=-0.28, P=.03). Similar results were obtained in the meta-regression analysis.

CONCLUSIONS

Arterial stiffness is not reduced in (pre)hypertensive subjects in response to aerobic training unless associated with a substantial reduction in SBP and/or prolonged duration.

Normobaric hypoxia training causes more weight loss than normoxia training after a 4-week residential camp for obese young adults

BACKGROUND

Intermittent normobaric hypoxia training, an alternative to altitude training for athletes, may be beneficial to treat overweight and obesity. The purpose of this study is to investigate whether normobaric hypoxia training combined with low-caloric diet has the additive effect on weight loss compared with normoxia training in obese young adults.

METHODS

Twenty-two subjects (age 17-25 years, body mass index >27.5 kg/m(2)) were recruited for a 4-week residential camp of weight loss with low caloric intake, and trained at 60-70% maximal heart rate of aerobics and 40-50% of maximal strength of training. They were randomly assigned to either a normobaric hypoxia (HT, FiO2 = 16.4-14.5 %) or normoxia training group (NT, FiO2 = 21%), and subjects in HT and NT groups experienced weekly 16-h normoxia and 6-h hypoxia or 22-h normoxia training, respectively. Body composition, resting blood pressure (BP) and brachial-ankle pulse wave velocity (baPWV) were determined before and after the intervention.

RESULTS

Weight loss was found in HT (-6.9 kg or -7.0%, p < 0.01) and NT groups (-4.3 kg or -4.2%, p < 0.01) significantly, and the former lost more weight than the latter (p < 0.01). Hypoxia training improved systolic BP (-7.6%) and mean BP (-7.1%) significantly (p < 0.05) despite having no effect on baPWV.

CONCLUSION

Four weeks of normobaric hypoxia residential training with low caloric diet has an additive improvement on weight loss. It seems that normobaric hypoxia training might be a promising method to treat obesity.

Multicomponent supplement containing Chlorella decreases arterial stiffness in healthy young men

Chlorella, a unicellular green alga, contains various antioxidants and other nutrients such as amino acids and fiber. Previous studies have reported that supplementation with multiple antioxidants reduces arterial stiffness, a well-established cardiovascular risk factor. We investigated the effects of Chlorella intake on arterial stiffness using a single-blinded, placebo-controlled crossover study design. Fourteen young men took placebo or Chlorella tablets for four weeks, with a 12-week washout period between trials, in a randomized order. Before and after each trial, blood pressure, heart rate, and brachial-ankle pulse wave velocity, an index of arterial stiffness, were measured. Treatment compliance was comparable between the two groups. There were no differences in blood pressure and heart rate before and after supplementation in both the placebo and Chlorella groups. Brachial-ankle pulse wave velocity decreased after Chlorella intake (before vs after intake; 11.6 ± 0.2 vs 11.1 ± 0.1 m/s, p = 0.01), but not after placebo intake (11.4 ± 0.2 vs 11.4 ± 0.2 m/s, p = 0.98). Multicomponent analysis of the Chlorella-containing tablet detected nutrients that can reduce arterial stiffness, such as antioxidant vitamins, arginine, potassium, calcium, and n-3 unsaturated fatty acids. These results suggest that intake of a Chlorella-containing multicomponent supplement can decrease arterial stiffness.

Heat acclimation increases arterial elasticity in young men

The major physiological adaptations that occur during heat acclimation (HA) are well documented. However, no studies have provided compelling evidence about the effect of HA on arterial elastic properties. The aim of this study was to examine the changes in large artery elasticity (LAE) and small artery elasticity (SAE) concomitant with HA and to determine the potential relationships among changes in arterial elasticity, baseline aerobic fitness level, and improvement in endurance capacity (EC). During 10-day HA, the subjects (n = 21) exercised daily on a treadmill for 110 min at an intensity of 55%–60% of peak oxygen uptake in a climatic chamber preset to 42 °C and 18% relative humidity. EC was tested in the heat before and after HA. Arterial elasticity was assessed by diastolic pulse wave analysis (HDI/Pulse Wave CR-2000) at baseline and after HA. Blood samples were drawn at baseline. After HA, there was a 17% increase in LAE (from 21.19 ± 4.72 mL·mm Hg−1 × 10 to 24.77 ± 5.91 mL·mm Hg−1 × 10, p < 0.05) and an 18% increase in SAE (from 9.32 ± 1.76 mL·mm Hg−1 × 100 to 10.98 ± 1.75 mL·mm Hg−1 × 100, p < 0.01). EC increased by 86% (from 88.62 ± 27.51 min to 161.95 ± 47.80 min, p < 0.001) as a result of HA. No significant associations were revealed between changes in arterial elasticity parameters and improvement in EC or baseline aerobic fitness level. We demonstrated, for the first time, that HA has a positive impact on the parameters of arterial elasticity. Further investigations are needed to determine the mechanisms underlying these changes and the potential relationships among arterial elasticity, aerobic fitness level, and EC.

The effect of exercise on osteoprotegerin and TNF-related apoptosis-inducing ligand in obese patients

BACKGROUND

Biomarkers of cardiovascular (CV) risk are tests that predict a patient's risk of future CV events. Recently, two proteins involved in vascular calcification; serum levels of osteoprotegerin (OPG) and tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) have emerged as potentially useful biomarkers. OPG levels are positively correlated with CV risk, whereas TRAIL levels show a negative correlation. Exercise training is known to reduce risk factors for CV disease by improving metabolism, vascular biology and blood flow. This study examined the effects of a 6-month exercise training programme on levels of OPG and TRAIL. Pulse wave velocity (PWV) and high-sensitivity C-reactive protein (hsCRP) were measured for comparative purposes.

MATERIALS AND METHODS

Overweight and obese patients undertook a 6-month exercise programme. Patients participated in 4 h of primarily aerobic exercise per week of which 2 h were supervised. At the beginning and end of the programme, anthropometric measurements, PWV and serum levels of OPG, TRAIL and hsCRP were measured.

RESULTS

A total of 21 patients (17 men) aged 55.2 ± 10 years completed the programme. Mean body mass index decreased from 34.1 ± 5.8 to 32.6 ± 5.4 kg/m(2) (P<0.05), while waist circumference decreased from 111.8 ± 12.4 to 109.6 ± 12.8 cm (P<0.05). PWV decreased from 9.2 to 8.5 m/s (P<0.02). OPG, TRAIL and hsCRP levels did not change significantly.

CONCLUSIONS

Exercise training reduced PWV but not OPG, TRAIL or hsCRP in this population. These data suggest that while an intervention of this nature improves vascular tone, it does not exert significant effects on serum biomarkers related to atherosclerotic inflammation and calcification.

Blood flow restricted exercise and vascular function

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

Sprint interval and endurance training are equally effective in increasing muscle microvascular density and eNOS content in sedentary males

Sprint interval training (SIT) has been proposed as a time efficient alternative to endurance training (ET) for increasing skeletal muscle oxidative capacity and improving certain cardiovascular functions. In this study we sought to make the first comparisons of the structural and endothelial enzymatic changes in skeletal muscle microvessels in response to ET and SIT. Sixteen young sedentary males (age 21 ± SEM 0.7 years, BMI 23.8 ± SEM 0.7 kg m(-2)) were randomly assigned to 6 weeks of ET (40-60 min cycling at ∼65% , 5 times per week) or SIT (4-6 Wingate tests, 3 times per week). Muscle biopsies were taken from the m. vastus lateralis before and following 60 min cycling at 65% to measure muscle microvascular endothelial eNOS content, eNOS serine(1177) phosphorylation, NOX2 content and capillarisation using quantitative immunofluorescence microscopy. Whole body insulin sensitivity, arterial stiffness and blood pressure were also assessed. ET and SIT increased skeletal muscle microvascular eNOS content (ET 14%; P < 0.05, SIT 36%; P < 0.05), with a significantly greater increase observed following SIT (P < 0.05). Sixty minutes of moderate intensity exercise increased eNOS ser(1177) phosphorylation in all instances (P < 0.05), but basal and post-exercise eNOS ser(1177) phosphorylation was lower following both training modes. All microscopy measures of skeletal muscle capillarisation (P < 0.05) were increased with SIT or ET, while neither endothelial nor sarcolemmal NOX2 was changed. Both training modes reduced aortic stiffness and increased whole body insulin sensitivity (P < 0.05). In conclusion, in sedentary males SIT and ET are effective in improving muscle microvascular density and eNOS protein content.

Vascular adaptations to hypobaric hypoxic training in postmenopausal women

The objective of this study was to examine the effects of exercise training in hypoxia on arterial stiffness and flow-mediated vasodilation (FMD) in postmenopausal women. Sixteen postmenopausal women (56±1 years) were assigned to a normoxic exercise group (Normoxic group, n=8) or a hypoxic exercise group (Hypoxic group, n=8). The Hypoxic group performed exercise under hypobaric hypoxic conditions corresponding to 2000 m above sea level, and was exposed to these conditions for 2 h per session. Aquatic exercise was performed at an intensity of around 50% peak oxygen uptake for 30min, 4days per week, for 8 weeks. Arterial stiffness was assessed by brachial-ankle pulse wave velocity (baPWV), and FMD was evaluated by peak diameter of the popliteal artery during reactive hyperemia. After the 8 weeks of training, the Normoxic group showed no significant changes. In contrast, baPWV (P < 0.05) was significantly reduced and peak diameter (P<0.05) and %FMD (P<0.01) were significantly increased in the Hypoxic group after training. These results suggest that exercise training under mild intermittent hypoxic conditions could more effectively reduce arterial stiffness in postmenopausal women, compared with exercise training performed at the same relative intensity under normoxic conditions. Our data also indicate that hypoxic exercise training may induce vascular functional adaptation, for example an increase in FMD response. These findings therefore could have important implications for the development of a new effective exercise prescription program.

Arterial stiffness and wave reflections in marathon runners

BACKGROUND

Regular aerobic exercise has beneficial effects on the cardiovascular system. Marathon running is an aerobic and extremely vigorous exercise. Arterial stiffness and wave reflections are independent predictors of cardiovascular risk. We investigated the acute effect of marathon race on aortic stiffness and wave reflections, as well as possible chronic alterations of these indexes in marathon runners.

METHODS

We studied 49 marathon runners (age 38 +/- 9 years) and 46 recreationally active control subjects (age 37 +/- 5 years). To investigate the acute effect of marathon race, a subgroup of 20 runners was evaluated after the race as well. Aortic stiffness was evaluated with carotid-femoral pulse wave velocity (PWV) and wave reflections with augmentation index (AIx).

RESULTS

Marathon runners had significantly higher systolic, diastolic, pulse (both aortic and brachial), and mean pressures compared to controls (P < 0.05 for all). Marathon runners had significantly higher PWV (6.89 m/s vs. 6.33 m/s, P < 0.01), whereas there was no difference in AIx and AIx corrected for heart rate (AIx@75) compared to controls (13.8% vs. 13.9%, P = 0.985 and 8.2% vs. 10.3%, P = 0.340, respectively). Marathon race caused a significant fall in both AIx (12.2% vs. -5.8%, P < 0.001) and AIx@75 (7.0% vs. 0.0%, P = 0.01), whereas PWV did not change significantly (6.66 m/s vs. 6.74 m/s, P = 0.690). Aortic and brachial systolic, diastolic, and mean pressures were also decreased (P < 0.05).

CONCLUSIONS

A significant fall in wave reflections was observed after marathon race, whereas aortic stiffness was not altered. Moreover, marathon runners have increased aortic stiffness and pressures, whereas wave reflections indexes do not differ compared to controls.

Effects of continuous vs. interval exercise training on blood pressure and arterial stiffness in treated hypertension

Exercise is an effective intervention for treating hypertension and arterial stiffness, but little is known about which exercise modality is the most effective in reducing arterial stiffness and blood pressure in hypertensive subjects. Our purpose was to evaluate the effect of continuous vs. interval exercise training on arterial stiffness and blood pressure in hypertensive patients. Sixty-five patients with hypertension were randomized to 16 weeks of continuous exercise training (n=26), interval training (n=26) or a sedentary routine (n=13). The training was conducted in two 40-min sessions a week. Assessment of arterial stiffness by carotid-femoral pulse wave velocity (PWV) measurement and 24-h ambulatory blood pressure monitoring (ABPM) were performed before and after the 16 weeks of training. At the end of the study, ABPM blood pressure had declined significantly only in the subjects with higher basal values and was independent of training modality. PWV had declined significantly only after interval training from 9.44+/-0.91 to 8.90+/-0.96 m s(-1), P=0.009 (continuous from 10.15+/-1.66 to 9.98+/-1.81 m s(-1), P=ns; control from 10.23+/-1.82 to 10.53+/-1.97 m s(-1), P=ns). Continuous and interval exercise training were beneficial for blood pressure control, but only interval training reduced arterial stiffness in treated hypertensive subjects.

Longitudinal changes in central artery stiffness with lifestyle modification, washout, and drug treatment in individuals at risk for cardiovascular disease

We assessed 17 middle-aged and older individuals (58.0 +/- 7.9 years, 7 females) at risk for cardiovascular disease regarding: (1) Whether carotid artery stiffness (cAS) would be reduced with a 1-year lifestyle modification program, (2) to what degree cAS would return following washout (mean of 26.9 +/- 4.0 months) from the active intervention, and (3) whether a 24-week telmisartan treatment would reduce cAS more than our lifestyle modification program. cAS by Doppler ultrasound, cardiovascular disease risk factors, and exercise capacity were assessed at three points: Following the 1-year lifestyle modification, following the washout period, and following a 24-week telmisartan treatment. Following telmisartan, systolic blood pressure (SBP) was significantly decreased (114.8 +/- 12.3 mmHg) compared to baseline (127.9 +/- 12.7 mmHg) and following the washout period (126.1 +/- 14.9 mmHg). Similarly, diastolic blood pressure (DBP) was significantly lower following telmisaratn than following the washout period. Exercise capacity was increased following lifestyle modification but returned to the baseline level following the washout period. Following the lifestyle modification program, cAS was significantly reduced, and this reduction was maintained following the washout period. Conversely, the subsequent telmisartan treatment did not change cAS despite a significant blood pressure reduction. These results suggest that the reduced cAS achieved with lifestyle modification may not necessarily disappear following a cessation of the active program, indicating a possible role that family physicians can play in their clinical practice, and also providing a further rationale to promote lifestyle modification as an initial therapy for this population. In contrast, no additional benefit of telmisartan beyond our lifestyle intervention was observed in this study.