The impact of handgrip exercise duty cycle on brachial artery flow-mediated dilation

Acute mental stress can impair brachial artery (BA) flow-mediated dilation (FMD) in response to reactive hyperemia (RH) induced increases in shear stress. Handgrip exercise (HGEX) is emerging as a useful tool to increase shear stress for FMD assessment; however, the impact of acute mental stress on HGEX-FMD is unknown. The purpose of this study was to determine whether acute mental stress attenuates RH- and HGEX-induced BA-FMD to a similar extent. In 2 counterbalanced visits, 16 healthy males (19–27 years of age) performed RH-FMD or HGEX-FMD tests after a counting control task (prestress FMD) and a speech and arithmetic stress task (poststress FMD). BA diameter and mean blood velocity were assessed with echo and Doppler ultrasound, respectively. Shear stress was estimated using shear rate (SR = BA blood velocity/BA diameter). Mean arterial pressure (MAP), heart rate (HR), and salivary cortisol were used to assess stress reactivity. Results are expressed as mean ± SE. The stress task elevated MAP (Δ24.0 ± 2.6 mm Hg) and HR (Δ15.5 ± 1.9 beats·min–1), but not cortisol (prestress vs. poststress: 4.4 ± 0.7 nmol·L–1 vs. 4.7 ± 0.7 nmol·L–1; p = 0.625). There was no difference between the pre- and poststress SR stimulus for RH (p = 0.115) or HGEX (p = 0.664). RH-FMD decreased from 5.2% ± 0.6% prestress to 4.1% ± 0.5% poststress (p = 0.071); however, stress did not attenuate HGEX-FMD (prestress vs. poststress: 4.1% ± 0.6% vs. 5.3% ± 0.6%; p = 0.154). The pre- to poststress change in FMD was significantly different in the RH-FMD vs. the HGEX-FMD test (–1.1% ± 0.6% vs. +1.1% ± 0.8%; p = 0.015). In conclusion, acute mental stress appears to have a disparate impact on FMD stimulated by RH vs. HGEX induced increases in shear stress.

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The impact of menstrual phase on brachial artery flow-mediated dilatation during handgrip exercise in healthy premenopausal women

Experimental Physiology ◽

10.1113/ep086311 ◽

2017 ◽

Vol 103 (2) ◽

pp. 291-302 ◽

Cited By ~ 19

Author(s):

Katrina A. D'Urzo ◽

Trevor J. King ◽

Jennifer S. Williams ◽

Morgan D. Silvester ◽

Kyra E. Pyke

Keyword(s):

Brachial Artery ◽

Premenopausal Women ◽

Handgrip Exercise ◽

Menstrual Phase ◽

Flow Mediated Dilatation ◽

Artery Flow ◽

The Impact

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The impact of acute mental stress on brachial artery flow-mediated dilation in women diagnosed with depression

International Journal of Psychophysiology ◽

10.1016/j.ijpsycho.2018.12.003 ◽

2019 ◽

Vol 135 ◽

pp. 113-120 ◽

Cited By ~ 3

Author(s):

Katrina A. D'Urzo ◽

Cherie L. La Rocque ◽

Jennifer S. Williams ◽

Troy J.R. Stuckless ◽

Trevor J. King ◽

...

Keyword(s):

Brachial Artery ◽

Mental Stress ◽

Flow Mediated Dilation ◽

Artery Flow ◽

The Impact

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Effect of black tea consumption on brachial artery flow-mediated dilation and ischaemia–reperfusion in humans

Applied Physiology Nutrition and Metabolism ◽

10.1139/apnm-2012-0450 ◽

2014 ◽

Vol 39 (2) ◽

pp. 145-151 ◽

Cited By ~ 7

Author(s):

Tim H.A. Schreuder ◽

Thijs M.H. Eijsvogels ◽

Arno Greyling ◽

Richard Draijer ◽

Maria T.E. Hopman ◽

...

Keyword(s):

Endothelial Function ◽

Brachial Artery ◽

Black Tea ◽

Hot Water ◽

Flow Mediated Dilation ◽

Tea Consumption ◽

Ischaemia Reperfusion ◽

Artery Flow ◽

The Impact

Tea consumption is associated with reduced cardiovascular risk. Previous studies found that tea flavonoids work through direct effects on the vasculature, leading to dose-dependent improvements in endothelial function. Cardioprotective effects of regular tea consumption may relate to the prevention of endothelial ischaemia–reperfusion (IR) injury. Therefore, we examined the effect of black tea consumption on endothelial function and the ability of tea to prevent IR injury. In a randomized, crossover study, 20 healthy subjects underwent 7 days of tea consumption (3 cups per day) or abstinence from tea. We examined brachial artery (BA) endothelial function via flow-mediated dilation (FMD), using high resolution echo-Doppler, before and 90 min after tea or hot water consumption. Subsequently, we followed a 20-min ischaemia and 20-min reperfusion protocol of the BA after which we measured FMD to examine the potential of tea consumption to protect against IR injury. Tea consumption resulted in an immediate increase in FMD% (pre-consumption: 5.8 ± 2.5; post-consumption: 7.2 ± 3.2; p < 0.01), whilst no such change occurred after ingestion of hot water. The IR protocol resulted in a significant decrease in FMD (p < 0.005), which was also present after tea consumption (p < 0.001). This decline was accompanied by an increase in the post-IR baseline diameter. In conclusion, these data indicate that tea ingestion improves BA FMD. However, the impact of the IR protocol on FMD was not influenced by tea consumption. Therefore, the cardioprotective association of tea ingestion relates to a direct effect of tea on the endothelium in humans in vivo.

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Acute vascular responses to isometric handgrip exercise and effects of training in persons medicated for hypertension

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.01113.2005 ◽

2006 ◽

Vol 291 (4) ◽

pp. H1797-H1802 ◽

Cited By ~ 53

Author(s):

Cheri L. McGowan ◽

Andrew S. Levy ◽

Philip J. Millar ◽

Juan C. Guzman ◽

Carlos A. Morillo ◽

...

Keyword(s):

Brachial Artery ◽

Flow Mediated Dilation ◽

Handgrip Exercise ◽

Isometric Handgrip ◽

Acute Bout ◽

Vascular Responses ◽

Single Bout ◽

Isometric Handgrip Exercise ◽

Phd Thesis ◽

Artery Flow

Previous work from our laboratory demonstrated that isometric handgrip (IHG) training improved local, endothelium-dependent vasodilation in medicated hypertensives [McGowan CL (PhD Thesis), 2006; McGowan et al. Physiologist 47: 285, 2004]. We investigated whether changes in the capacity of smooth muscle to dilate (regardless of endothelial factors) influenced this training-induced change, and we examined the acute vascular responses to a single bout of IHG. Seventeen subjects performed four 2-min unilateral IHG contractions at 30% of maximal voluntary effort, three times a week for 8 wk. Pre- and posttraining, brachial artery flow-mediated dilation (FMD, an index of endothelium-dependent vasodilation) and nitroglycerin-mediated maximal vasodilation (an index of endothelium-independent vasodilation) were measured in the exercised arm by using ultrasound before and immediately after acute IHG exercise. IHG training resulted in improved resting brachial FMD ( P < 0.01) and no change in nitroglycerin-mediated maximal vasodilation. Pre- and posttraining, brachial artery FMD decreased following an acute bout of IHG exercise (normalized to peak shear rate, pre-, before IHG exercise: 0.01 ± 0.002, after IHG exercise: 0.008 ± 0.002%/s−1; post-, before IHG exercise: 0.020 ± 0.003, after IHG exercise: 0.010 ± 0.003%/s−1; P < 0.01). Posttraining, resting brachial artery FMD improved yet nitroglycerin-mediated maximal vasodilation was unchanged in persons medicated for hypertension. This suggests that the training-induced improvements in the resting brachial artery FMD were not due to underlying changes in the forearm vasculature. Acute IHG exercise attenuated brachial artery FMD, and although this impairment may be interpreted as hazardous to medicated hypertensives with already dysfunctional endothelium, the effects appear transient as repeated exposure to the IHG stimulus improved resting endothelium-dependent vasodilation.

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