scholarly journals Acute supplementation ofN-acetylcysteine does not affect muscle blood flow and oxygenation characteristics during handgrip exercise

2016 ◽  
Vol 4 (7) ◽  
pp. e12748 ◽  
Author(s):  
Joshua R. Smith ◽  
Ryan M. Broxterman ◽  
Carl J. Ade ◽  
Kara K. Evans ◽  
Stephanie P. Kurti ◽  
...  
Keyword(s):  
Blood Flow ◽  
Muscle Blood Flow ◽  
Handgrip Exercise

Skeletal muscle blood flow and vascular conductance are enhanced in humans with high‐affinity hemoglobin during handgrip exercise in severe hypoxia

2020 ◽  
Vol 34 (S1) ◽  
pp. 1-1
Author(s):  
Chad C. Wiggins ◽  
Paolo B. Dominelli ◽  
Jonathon W. Senefeld ◽  
John R.A. Shepherd ◽  
Sarah E. Baker ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Blood Flow ◽  
Muscle Blood Flow ◽  
Severe Hypoxia ◽  
Handgrip Exercise ◽  
Vascular Conductance ◽  
Skeletal Muscle Blood Flow ◽  
High Affinity

scholarly journals Muscle Blood Flow and Oxygen Utilization Measured by Near-Infrared Spectroscopy during Handgrip Exercise in Chronic Respiratory Patients

2009 ◽  
Vol 21 (3) ◽  
pp. 231-238 ◽  
Author(s):  
Kiyokazu Sekikawa ◽  
Kazuyuki Tabira ◽  
Noriko Sekikawa ◽  
Kotarou Kawaguchi ◽  
Makoto Takahashi ◽  
...  
Keyword(s):  
Blood Flow ◽  
Infrared Spectroscopy ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Muscle Blood Flow ◽  
Handgrip Exercise ◽  
Oxygen Utilization

scholarly journals Acute ascorbic acid ingestion increases skeletal muscle blood flow and oxygen consumption via local vasodilation during graded handgrip exercise in older adults

2015 ◽  
Vol 309 (2) ◽  
pp. H360-H368 ◽  
Author(s):  
Jennifer C. Richards ◽  
Anne R. Crecelius ◽  
Dennis G. Larson ◽  
Frank A. Dinenno
Keyword(s):  
Older Adults ◽  
Skeletal Muscle ◽  
Blood Flow ◽  
Ascorbic Acid ◽  
Oxygen Consumption ◽  
Lower Body Negative Pressure ◽  
Muscle Blood Flow ◽  
Voluntary Contraction ◽  
Handgrip Exercise ◽  
Forearm Vascular Conductance

Human aging is associated with reduced skeletal muscle perfusion during exercise, which may be a result of impaired endothelium-dependent dilation and/or attenuated ability to blunt sympathetically mediated vasoconstriction. Intra-arterial infusion of ascorbic acid (AA) increases nitric oxide-mediated vasodilation and forearm blood flow (FBF) during handgrip exercise in older adults, yet it remains unknown whether an acute oral dose can similarly improve FBF or enhance the ability to blunt sympathetic vasoconstriction during exercise. We hypothesized that 1) acute oral AA would improve FBF (Doppler ultrasound) and oxygen consumption (V̇o2) via local vasodilation during graded rhythmic handgrip exercise in older adults ( protocol 1), and 2) AA ingestion would not enhance sympatholysis in older adults during handgrip exercise ( protocol 2). In protocol 1 ( n = 8; 65 ± 3 yr), AA did not influence FBF or V̇o2 during rest or 5% maximal voluntary contraction (MVC) exercise, but increased FBF (199 ± 13 vs. 248 ± 16 ml/min and 343 ± 24 vs. 403 ± 33 ml/min; P < 0.05) and V̇o2 (26 ± 2 vs. 34 ± 3 ml/min and 43 ± 4 vs. 50 ± 5 ml/min; P < 0.05) at both 15 and 25% MVC, respectively. The increased FBF was due to elevations in forearm vascular conductance (FVC). In protocol 2 ( n = 10; 63 ± 2 yr), following AA, FBF was similarly elevated during 15% MVC (∼20%); however, vasoconstriction to reflex increases in sympathetic activity during −40 mmHg lower-body negative pressure at rest (ΔFVC: −16 ± 3 vs. −16 ± 2%) or during 15% MVC (ΔFVC: −12 ± 2 vs. −11 ± 4%) was unchanged. Our collective results indicate that acute oral ingestion of AA improves muscle blood flow and V̇o2 during exercise in older adults via local vasodilation.

Muscle Blood Flow as a Determinant of Exercise Tolerance During Intermittent Isometric and Dynamic Handgrip Exercise

2006 ◽  
Vol 38 (Supplement) ◽  
pp. S193 ◽  
Author(s):  
Julie A. Wilhelm ◽  
Allison J. Harper ◽  
Benjamin C. Thompson ◽  
Barry W. Scheuermann
Keyword(s):  
Blood Flow ◽  
Exercise Tolerance ◽  
Muscle Blood Flow ◽  
Handgrip Exercise

Muscle Blood Flow Responses to Dynamic Handgrip Exercise in Young Obese Adults

2017 ◽  
Vol 49 (5S) ◽  
pp. 827
Author(s):  
Kanokwan Bunsawat ◽  
Georgios Grigoriadis ◽  
Garett Griffith ◽  
Sang Ouk Wee ◽  
Elizabeth Schroeder ◽  
...  
Keyword(s):  
Blood Flow ◽  
Muscle Blood Flow ◽  
Handgrip Exercise ◽  
Obese Adults

scholarly journals Measurement of muscle blood flow and O2 uptake via near-infrared spectroscopy using a novel occlusion protocol

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Joshua J. Dennis ◽  
Chad C. Wiggins ◽  
Joshua R. Smith ◽  
Jennifer M. J. Isautier ◽  
Bruce D. Johnson ◽  
...  
Keyword(s):  
Blood Flow ◽  
Infrared Spectroscopy ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Muscle Blood Flow ◽  
Arterial Occlusion ◽  
Vascular Occlusion ◽  
Voluntary Contraction ◽  
Handgrip Exercise ◽  
Perfect Agreement

AbstractWe describe here a novel protocol that sequentially combines venous followed by arterial occlusions to determine muscle blood flow and O2 uptake from a single measurement point using near-infrared spectroscopy (NIRS) during handgrip exercise. NIRS data were obtained from the flexor digitorum superficialis (FDS) muscle on the dominant arm of 15 young, healthy adults (3 women; 26 ± 7 years; 78.6 ± 9.1 kg). Participants completed a series of 15-s static handgrip contractions at 20, 40 and 60% of maximal voluntary contraction (MVC) immediately followed by either a: (i) venous occlusion (VO); (ii); arterial occlusion (AO); or venous then arterial occlusion (COMBO). Each condition was repeated 3 times for each exercise-intensity. The concordance correlation coefficient (CCC) and robust linear mixed effects modeling were used to determine measurement agreement between vascular occlusion conditions. FDS muscle blood flow ($${\dot{\text{Q}}}_{{{\text{FDS}}}}$$ Q ˙ FDS ) and conductance ($${\text{C}}_{{{\text{FDS}}}}$$ C FDS ) demonstrated strong absolute agreement between VO and COMBO trials from rest up to 60%MVC, as evidenced by high values for CCC (> 0.82) and a linear relationship between conditions that closely approximated the line-of-identity (perfect agreement). Conversely, although FDS muscle O2 uptake ($${{\dot {\text{V}}}}{{\text{O}}_{2{\text{FDS}}}}$$ V ˙ O 2 FDS ) displayed “substantial” to “near perfect” agreement between methods across exercise intensities (i.e., CCC > 0.80), there was a tendency for COMBO trials to underestimate $${{\dot {\text{V}}}}{{\text{O}}_{2{\text{FDS}}}}$$ V ˙ O 2 FDS by up to 7%. These findings indicate that the COMBO method provides valid estimates of $${\dot {\text{Q}}}_{{\text{FDS}}}$$ Q ˙ FDS and, to a slightly lesser extent, $${{\dot {\text{V}}}}{{\text{O}}_{2{\text{FDS}}}}$$ V ˙ O 2 FDS at rest and during static handgrip exercise up to 60%MVC. Practical implications and suggested improvements of the method are discussed.

scholarly journals Tetrahydrobiopterin Administration Augments Exercise-Induced Hyperemia and Endothelial Function in Patients With Systemic Sclerosis

2022 ◽  
Vol 8 ◽  
Author(s):  
Daniel R. Machin ◽  
Heather L. Clifton ◽  
D. Walter Wray ◽  
Tracy M. Frech ◽  
Anthony J. Donato
Keyword(s):  
Blood Flow ◽  
Systemic Sclerosis ◽  
Shear Rate ◽  
Endothelial Function ◽  
Brachial Artery ◽  
Muscle Blood Flow ◽  
Fold Increase ◽  
Acute Administration ◽  
Handgrip Exercise ◽  
Double Blind

Systemic sclerosis (SSc) is a rare, auto-immune disease with variably progressive fibrosis of the skin and internal organs, as well as vascular dysfunction. Recently, we demonstrated a decrement in exercising skeletal muscle blood flow and endothelium-dependent vasodilation in SSc, but the mechanisms responsible for these impairments have not been investigated. Thus, we sought to determine if acute administration of tetrahydrobiopterin (BH4), an essential cofactor for endothelial nitric oxide synthase (eNOS), would improve hyperemia and brachial artery vasodilation during progressive handgrip exercise in SSc. Thirteen patients with SSc (63 ± 11 years) participated in this placebo-controlled, randomized, double-blind, crossover study. Tetrahydrobiopterin (10 mg/kg) administration resulted in a ~4-fold increase in circulating BH4 concentrations (P &lt; 0.05). Cardiovascular variables at rest were unaffected by BH4 (P &gt; 0.05). During handgrip exercise, BH4 administration increased brachial artery blood flow (placebo: 200 ± 87; BH4: 261 ± 115 ml/min; P &lt; 0.05) and vascular conductance (placebo: 2.0 ± 0.8; BH4: 2.5 ± 1.0 ml/min/mmHg; P &lt; 0.05), indicating augmented resistance artery vasodilation. Tetrahydrobiopterin administration also increased brachial artery vasodilation in response to exercise (placebo: 12 ± 6; BH4: 17 ± 7%; P &lt; 0.05), resulting in a significant upward shift in the slope relationship between Δ brachial artery vasodilation and Δ shear rate (placebo: 0.030 ± 0.007; BH4: 0.047 ± 0.007; P &lt; 0.05) that indicates augmented sensitivity of the brachial artery to vasodilate to the sustained elevations in shear rate during handgrip exercise. These results demonstrate the efficacy of acute BH4 administration to improve both resistance and conduit vessel endothelial function in SSc, suggesting that eNOS recoupling may be an effective strategy for improving vasodilatory capacity in this patient group.

Evaluation of muscle metaboreflex function through graded reduction in forearm blood flow during rhythmic handgrip exercise in humans

2011 ◽  
Vol 301 (2) ◽  
pp. H609-H616 ◽  
Author(s):  
Masashi Ichinose ◽  
Stephane Delliaux ◽  
Kazuhito Watanabe ◽  
Naoto Fujii ◽  
Takeshi Nishiyasu
Keyword(s):  
Blood Flow ◽  
Forearm Blood Flow ◽  
Pressor Response ◽  
Muscle Blood Flow ◽  
Voluntary Contraction ◽  
Open Loop ◽  
Handgrip Exercise ◽  
Hemodynamic Responses ◽  
Muscle Metaboreflex ◽  
Arterial Blood

Hypoperfusion of active skeletal muscle elicits a reflex pressor response termed the muscle metaboreflex. Our aim was to determine the muscle metaboreflex threshold and gain in humans by creating an open-loop relationship between active muscle blood flow and hemodynamic responses during a rhythmic handgrip exercise. Eleven healthy subjects performed the exercise at 5 or 15% of maximal voluntary contraction (MVC) in random order. During the exercise, forearm blood flow (FBF), which was continuously measured using Doppler ultrasound, was reduced in five steps by manipulating the inner pressure of an occlusion cuff on the upper arm. The FBF at each level was maintained for 3 min. The initial reductions in FBF elicited no hemodynamic changes, but once FBF fell below a threshold, mean arterial blood pressure (MAP) and heart rate (HR) increased and total vascular conductance (TVC) decreased in a linear manner. The threshold FBF during the 15% MVC trial was significantly higher than during the 5% MVC trial. The gain was then estimated as the slope of the relationship between the hemodynamic responses and FBFs below the threshold. The gains for the MAP and TVC responses did not differ between workloads, but the gain for the HR response was greater in the 15% MVC trial. Our findings thus indicate that increasing the workload shifts the threshold for the muscle metaboreflex to higher blood flows without changing the gain of the reflex for the MAP and TVC responses, whereas it enhances the gain for the HR response.

scholarly journals Influence of sympathetic vasoconstriction on muscle blood flow control during graded handgrip exercise in young and older adults (1165.2)

2014 ◽  
Vol 28 (S1) ◽  
Author(s):  
Jennifer Richards ◽  
Anne Crecelius ◽  
Christoper Hearon ◽  
Matthew Racine ◽  
Dennis Larson ◽  
...  
Keyword(s):  
Older Adults ◽  
Blood Flow ◽  
Flow Control ◽  
Muscle Blood Flow ◽  
Handgrip Exercise ◽  
Sympathetic Vasoconstriction ◽  
Blood Flow Control

scholarly journals Effect of dietary nitrate supplementation on conduit artery blood flow, muscle oxygenation, and metabolic rate during handgrip exercise

2018 ◽  
Vol 125 (2) ◽  
pp. 254-262 ◽  
Author(s):  
Jesse C. Craig ◽  
Ryan M. Broxterman ◽  
Joshua R. Smith ◽  
Jason D. Allen ◽  
Thomas J. Barstow
Keyword(s):  
Blood Flow ◽  
Muscle Mass ◽  
Muscle Blood Flow ◽  
Muscle Oxygenation ◽  
Moderate Intensity ◽  
Handgrip Exercise ◽  
Exercise Tests ◽  
Dietary Nitrate ◽  
Positive Effects ◽  
Nitrate Supplementation

Dietary nitrate supplementation has positive effects on mitochondrial and muscle contractile efficiency during large muscle mass exercise in humans and on skeletal muscle blood flow (Q̇) in rats. However, concurrent measurement of these effects has not been performed in humans. Therefore, we assessed the influence of nitrate supplementation on Q̇ and muscle oxygenation characteristics during moderate- (40 %peak) and severe-intensity(85% peak) handgrip exercise in a randomized, double-blind, crossover design. Nine healthy men (age: 25 ± 2 yr) completed four constant-power exercise tests (2/intensity) randomly assigned to condition [nitrate-rich (nitrate) or nitrate-poor (placebo) beetroot supplementation] and intensity (40 or 85% peak). Resting mean arterial pressure was lower after nitrate compared with placebo (84 ± 4 vs. 89 ± 4 mmHg, P < 0.01). All subjects were able to sustain 10 min of exercise at 40% peak in both conditions. Nitrate had no effect on exercise tolerance during 85% peak (nitrate: 358 ± 29; placebo: 341 ± 34 s; P = 0.3). Brachial artery Q̇ was not different after nitrate at rest or any time during exercise. Deoxygenated [hemoglobin + myoglobin] was not different for 40% peak ( P > 0.05) but was elevated throughout 85% peak ( P < 0.05) after nitrate. The metabolic cost (V̇o2) was not different at the end of exercise; however, the V̇o2 primary amplitude at the onset of exercise was elevated after nitrate for the 85% peak work rate (96 ± 20 vs. 72 ± 12 ml/min, P < 0.05) and had a faster response. These findings suggest that an acute dose of nitrate reduces resting blood pressure and speeds V̇o2 kinetics in young adults but does not augment Q̇ or reduce steady-state V̇o2 during small muscle mass handgrip exercise. NEW & NOTEWORTHY We show that acute dietary nitrate supplementation via beetroot juice increases the amplitude and speed of local muscle V̇o2 on kinetics parameters during severe- but not moderate-intensity handgrip exercise. These changes were found in the absence of an increased blood flow response, suggesting that the increased V̇o2 was attained via improvements in fractional O2 extraction and/or spatial distribution of blood flow within the exercising muscle.

Sign in / Sign up

Export Citation Format

Share Document