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Featured researches published by Roy Kalfon.


Journal of the Academy of Nutrition and Dietetics | 2015

Daily Blueberry Consumption Improves Blood Pressure and Arterial Stiffness in Postmenopausal Women with Pre- and Stage 1-Hypertension: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Sarah A. Johnson; Arturo Figueroa; Negin Navaei; Alexei Wong; Roy Kalfon; Lauren T. Ormsbee; Rafaela G. Feresin; Marcus L. Elam; Shirin Hooshmand; Mark E. Payton; Bahram H. Arjmandi

BACKGROUND Postmenopausal women have a high prevalence of hypertension and often develop arterial stiffness thereby increasing cardiovascular disease risk. Although antihypertensive drug therapies exist, increasing numbers of people prefer natural therapies. In vivo studies and a limited number of clinical studies have demonstrated the antihypertensive and vascular-protective effects of blueberries. OBJECTIVE To examine the effects of daily blueberry consumption for 8 weeks on blood pressure and arterial stiffness in postmenopausal women with pre- and stage 1-hypertension. DESIGN This was an 8-week, randomized, double-blind, placebo-controlled clinical trial. PARTICIPANTS/SETTING Forty-eight postmenopausal women with pre- and stage 1-hypertension recruited from the greater Tallahassee, FL, area participated. INTERVENTION Participants were randomly assigned to receive either 22 g freeze-dried blueberry powder or 22 g control powder. MAIN OUTCOME MEASURES Resting brachial systolic and diastolic blood pressures were evaluated and arterial stiffness was assessed using carotid-femoral pulse wave velocity and brachial-ankle pulse wave velocity. C-reactive protein, nitric oxide, and superoxide dismutase were measured at baseline, 4 weeks, and 8 weeks. STATISTICAL ANALYSES PERFORMED Statistical analysis was performed using a split plot model of repeated measures analysis of variance. RESULTS After 8 weeks, systolic blood pressure and diastolic blood pressure (131±17 mm Hg [P<0.05] and 75±9 mm Hg [P<0.01], respectively) and brachial-ankle pulse wave velocity (1,401±122 cm/second; P<0.01) were significantly lower than baseline levels (138±14 mm Hg, 80±7 mm Hg, and 1,498±179 cm/second, respectively), with significant (P<0.05) group×time interactions in the blueberry powder group, whereas there were no changes in the group receiving the control powder. Nitric oxide levels were greater (15.35±11.16 μmol/L; P<0.01) in the blueberry powder group at 8 weeks compared with baseline values (9.11±7.95 μmol/L), whereas there were no changes in the control group. CONCLUSIONS Daily blueberry consumption may reduce blood pressure and arterial stiffness, which may be due, in part, to increased nitric oxide production.


Menopause | 2014

Whole-body vibration exercise training reduces arterial stiffness in postmenopausal women with prehypertension and hypertension.

Arturo Figueroa; Roy Kalfon; Takudzwa A. Madzima; Alexei Wong

ObjectiveThe purpose of this study was to examine the impact of whole-body vibration (WBV) exercise training on arterial stiffness (pulse wave velocity [PWV]), blood pressure (BP), and leg muscle function in postmenopausal women. MethodsTwenty-five postmenopausal women with prehypertension and hypertension (mean [SE]; age, 56 [1] y; systolic BP, 139 [2] mm Hg; body mass index, 34.7 [0.8] kg/m2) were randomized to 12 weeks of WBV exercise training (n = 13) or to the no-exercise control group. Systolic BP, diastolic BP, mean arterial pressure, heart rate, carotid-femoral PWV, brachial-ankle PWV, femoral-ankle PWV (legPWV), leg lean mass, and leg muscle strength were measured before and after 12 weeks. ResultsThere was a group-by-time interaction (P < 0.05) for arterial stiffness, BP, and strength as brachial-ankle PWV (−1.3 [0.3] m/s, P < 0.01), legPWV (−0.81 [0.22] m/s, P < 0.01), systolic BP (−12 [3] mm Hg, P < 0.01), diastolic BP (−6 [2] mm Hg, P < 0.01), and mean arterial pressure (−9 [3] mm Hg, P < 0.01) decreased and as strength increased (21.0% [2.2%], P < 0.001) after WBV exercise training compared with no change after control. Heart rate decreased (−3 [1] beats/min, P < 0.05) after WBV exercise training, but there was no interaction (P > 0.05). Leg lean mass and carotid-femoral PWV were not significantly (P > 0.05) affected by WBV exercise training or control. ConclusionsOur findings indicate that WBV exercise training improves systemic and leg arterial stiffness, BP, and leg muscle strength in postmenopausal women with prehypertension or hypertension. WBV exercise training may decrease cardiovascular and disability risks in postmenopausal women by reducing legPWV and increasing leg muscle strength.


American Journal of Hypertension | 2014

Effects of Milk Proteins and Combined Exercise Training on Aortic Hemodynamics and Arterial Stiffness in Young Obese Women With High Blood Pressure

Arturo Figueroa; Alexei Wong; Amber W. Kinsey; Roy Kalfon; Wyatt Eddy; Michael J. Ormsbee

BACKGROUND Obesity and reduced muscle strength are associated with increased blood pressure (BP). We examined the impact of milk proteins and combined exercise training (CET) on BP, arterial function, and muscle strength (one-repetition maximum (1-RM)). METHODS Thirty-three obese sedentary women (age = 30 ± 1 years; body mass index = 35.2 ± 0.9 kg/m(2); systolic BP (SBP) = 129 ± 2 mm Hg) were randomized to control carbohydrate (n = 11), whey (n = 11), and casein (n = 11) supplementation for 4 weeks. All participants performed moderate-intensity CET 3 days/week. Brachial and aortic SBP, augmentation index adjusted for 75 beats/minute (AIx@75), arterial stiffness (brachial-ankle pulse wave velocity (baPWV)), and 1-RM were measured before and after the interventions. RESULTS There were significant (P < 0.05) time-by-group interactions for brachial SBP (bSBP), aortic SBP (aSBP), AIx@75, and baPWV. Whey and casein supplementation significantly (P < 0.05) decreased bSBP (approximately 5mm Hg for both), aSBP (approximately 7 mm Hg and approximately 6mm Hg, respectively), AIx@75 (approximately 9.2% and approximately 8.1%, respectively) and baPWV (approximately 57 cm/s and approximately 53 cm/s, respectively) compared with no changes in the control group. Upper- (approximately 22.2%) and lower-body 1-RM (approximately 44.0%) increased similarly in all groups. Changes in arterial function and 1-RM were not correlated. CONCLUSIONS Milk protein supplementation with CET reduced SBP, wave reflection, and arterial stiffness in young obese women with prehypertension and hypertension. Because CET did not affect arterial function, milk proteins may have an antihypertensive effect by improving arterial function, as shown by reduced AIx@75 and baPWV. Muscle strength improvements after CET did not affect BP and arterial function. CLINICAL TRIAL REGISTRATION ClinicalTrial.gov Registration NCT01830946.


American Journal of Hypertension | 2014

Effects of Watermelon Supplementation on Aortic Hemodynamic Responses to the Cold Pressor Test in Obese Hypertensive Adults

Arturo Figueroa; Alexei Wong; Roy Kalfon

BACKGROUND Cold-induced increases in aortic blood pressure (BP) may cause adverse cardiac events in hypertensives by increasing ventricular afterload. L-citrulline supplementation reduces BP at baseline and during the cold pressor test (CPT), but the effect on wave reflection (augmentation pressure (AP) and index (AIx)) is controversial. Our aim was to assess the effect of L-citrulline-rich watermelon supplementation on aortic hemodynamic responses to CPT in hypertensive adults. METHODS Brachial systolic BP (bSBP) and aortic systolic BP (aSBP), AP, AIx, AIx adjusted to 75 beats/min (AIx75), reflection time (Tr), first (P1) and second systolic peak (P2; wave reflection magnitude), heart rate (HR), and systolic time index (STI; myocardial oxygen demand) at baseline and during CPT and magnitude of the response from baseline to CPT were evaluated in 13 individuals (10 women; 57±1 year; bSBP 151±5 mm Hg). Participants were randomized to a 6-week watermelon or placebo supplementation in a crossover design. RESULTS Watermelon reduced (P < 0.05) bSBP, aSBP, P1, and P2 at baseline and CPT compared with placebo; thus, increases from baseline to CPT were unaffected. Watermelon did not affect AP, AIx, AIx75, and STI at baseline but decreased (P < 0.05) AP and STI during CPT and the increases in AP (~5mm Hg) and AIx75 (~7.3%) from baseline to CPT. CONCLUSIONS Watermelon supplementation reduced aortic BP and myocardial oxygen demand during CPT and the magnitude of the cold-induced increase in wave reflection in obese adults with hypertension. Watermelon may provide cardioprotection by attenuating cold-induced aortic hemodynamic responses. CLINICAL TRIALS REGISTRATION Clinicaltrial.gov register, NCT01185041.


Menopause | 2015

Whole-body vibration training decreases ankle systolic blood pressure and leg arterial stiffness in obese postmenopausal women with high blood pressure

Arturo Figueroa; Roy Kalfon; Alexei Wong

ObjectiveHigh ankle systolic blood pressure (SBP; ≥175 mm Hg) is associated with arterial stiffness (pulse wave velocity [PWV]) and cardiac events. This study aims to investigate the effects of whole-body vibration (WBV) training on ankle SBP and its associations with changes in PWV and aortic SBP in postmenopausal women. MethodsThirty-six postmenopausal women were randomized to a control group (n = 12) or a WBV training group (3 d/wk) that was stratified by ankle SBP into WBV-high (n = 12) and WBV-normal (n = 12). Ankle SBP, brachial SBP, aortic SBP, femoral-ankle PWV (legPWV), carotid-femoral PWV, and brachial-ankle PWV (baPWV) were examined before and after 12 weeks. ResultsBaseline ankle SBP was higher (P < 0.05) in the WBV-high group compared with the WBV-normal group. WBV-high reduced mean (SEM) ankle SBP (−24 [7] mm Hg, P < 0.05) compared with WBV-normal and control. Both WBV groups decreased (P < 0.05) mean (SEM) brachial SBP (−11 [2] mm Hg), aortic SBP (−11 [3] mm Hg), legPWV (−0.80 [0.17] m/s), and baPWV (−1.18 [0.27] m/s) compared with the control group. Reductions in legPWV were correlated (P < 0.05) with decreases in ankle SBP (r = 0.43), brachial SBP (r = 0.42), aortic SBP (r = 0.42), and baPWV (r = 0.75). ConclusionsWBV training decreases ankle SBP in postmenopausal women with high ankle SBP. WBV training reduces aortic SBP, legPWV, and baPWV, but not carotid-femoral PWV, in postmenopausal women independently of ankle SBP. Therefore, reductions in peripheral and central SBP induced by WBV training are explained by a reduction in peripheral PWV.


American Journal of Hypertension | 2015

Aortic Hemodynamics and Arterial Stiffness Responses to Muscle Metaboreflex Activation With Concurrent Cold Pressor Test.

Roy Kalfon; Jeremiah C. Campbell; Stacey Alvarez-Alvarado; Arturo Figueroa

BACKGROUND Overweight/obese young men have increased sympatho-excitation to cold and pain stress-induced by the cold pressor test (CPT) that may lead to abnormal hemodynamic responses. Concurrent CPT and exercise may augment the sympathetic-induced increases in aortic blood pressure (BP), pressure wave reflection (augmentation index, AIx), and arterial stiffness (pulse wave velocity, PWV). Since obesity is related with hypertension and sympathetic activity, we evaluated the aortic hemodynamic and PWV responses to muscle metaboreflex activation imposed by postexercise muscle ischemia (PEMI) concurrent with CPT in overweight/obese men. METHODS In 16 healthy (body mass index >25 and <40kg/m(2)) men (24±2 years), heart rate (HR), brachial BP, aortic BP, augmented pressure (AP), AIx, AIx adjusted to 75 beats/min (AIx@75), reflection time (Tr), first (P1) and second systolic peak (P2, wave reflection magnitude), and PWV (brachial-ankle PWV, baPWV) were evaluated at baseline, during isometric-handgrip exercise (IHG), and PEMI with (PEMI + CPT) and without CPT. RESULTS During IHG, brachial BP, aortic BP, AP, AIx, AIx@75, P1, and P2 increased ( P < 0.01) while Tr decreased ( P < 0.05) compared with baseline. During PEMI, all hemodynamic parameters remained elevated ( P < 0.05) and baPWV increased (P < 0.05) while Tr and HR returned to baseline. Compared with PEMI, the increases in HR, brachial BP, aortic BP, AIx@75, P1, P2, and baPWV were greater ( P < 0.05) during PEMI + CPT. During PEMI + CPT, Tr remained lower ( P < 0.05) than baseline. CONCLUSIONS Cold exposure with concurrent metaboreflex activation induces a significant increase in aortic hemodynamics and arterial stiffness, which may explain the high risk of adverse cardiovascular events during physiological stress. CLINICAL TRIALS REGISTRATION Trial Number NCT02104375.


Archive | 2015

contraction at comparable workloads increased in response to static and dynamic muscle Wave reflection and central aortic pressure are

David G. Edwards; Corey R. Mastin; Robert W. Kenefick; Ellen A. Dawson; Mark A. Black; Daniel J. Green; Darren P. Casey; Timothy B. Curry; Michael J. Joyner; Nisha Charkoudian; Emma Hart; Roy Kalfon; Jeremiah C. Campbell; Stacey Alvarez-Alvarado; Arturo Figueroa


Medicine and Science in Sports and Exercise | 2015

L-Citrulline Supplementation Attenuates Cardiovascular Responses to Metaboreflex Activation with Cold Exposure in Young Overweight Men: 1002 Board #8 May 27, 3

Arturo Figueroa; Salvador J. Jaime; Jeremiah C. Campbell; Stacey Alvarez-Alvarado; Roy Kalfon


Medicine and Science in Sports and Exercise | 2015

Whole-Body Vibration Training Decreases Ankle Systolic Blood Pressure and Arterial Stiffness in Hypertensive Postmenopausal Women: 317 Board #168 May 27, 9

Jeremiah C. Campbell; Alexei Wong; Roy Kalfon; Arturo Figueroa


The FASEB Journal | 2014

Relationship between body composition and arterial stiffness in postmenopausal women (391.8)

Rafaela G. Feresin; Arturo Figueroa; Sarah A. Johnson; Marcus L. Elam; Roy Kalfon; Alexei Wong; Negin Navai; Shirin Pourafshar; Bahram H. Arjmandi

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Alexei Wong

Florida State University

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Marcus L. Elam

Florida State University

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