Impact Of Isometric Handgrip Exercise With Blood Flow Restriction On Interference Control And Affect

The dramatic increase in skin blood flow and sweating observed during heat stress is mediated by poorly understood sympathetic cholinergic mechanisms. One theory suggests that a single sympathetic cholinergic nerve mediates cutaneous active vasodilation (AVD) and sweating via cotransmission of separate neurotransmitters, because AVD and sweating track temporally and directionally when activated during passive whole body heat stress. It has also been suggested that these responses are regulated independently, because cutaneous vascular conductance (CVC) has been shown to decrease, whereas sweat rate increases, during combined hyperthermia and isometric handgrip exercise. We tested the hypothesis that CVC decreases during isometric handgrip exercise if skin blood flow is elevated using local heating to levels similar to that induced by pronounced hyperthermia but that this does not occur at lower levels of skin blood flow. Subjects performed isometric handgrip exercise as CVC was elevated at selected sites to varying levels by local heating (which is independent of AVD) in thermoneutral and hyperthermic conditions. During thermoneutral isometric handgrip exercise, CVC decreased at sites in which blood flow was significantly elevated before exercise (−6.5 ± 1.8% of maximal CVC at 41°C and −10.5 ± 2.0% of maximal CVC at 43°C; P < 0.05 vs. preexercise). During isometric handgrip exercise in the hyperthermic condition, an observed decrease in CVC was associated with the level of CVC before exercise. Taken together, these findings argue against withdrawal of AVD to explain the decrease in CVC observed during isometric handgrip exercise in hyperthermic conditions.

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Peripheral and Central Blood Pressure Response to Handgrip Exercise Coupled with Blood Flow Restriction

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000517010.28794.67 ◽

2017 ◽

Vol 49 (5S) ◽

pp. 67

Author(s):

Jeffrey D. Miller ◽

Edward T. Kelley ◽

Daniel P. Credeur

Keyword(s):

Blood Pressure ◽

Blood Flow ◽

Blood Pressure Response ◽

Pressure Response ◽

Blood Flow Restriction ◽

Central Blood Pressure ◽

Handgrip Exercise ◽

Flow Restriction

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Neural and non-neural control of skin blood flow during isometric handgrip exercise in the heat stressed human

The Journal of Physiology ◽

10.1113/jphysiol.2009.169201 ◽

2009 ◽

Vol 587 (9) ◽

pp. 2101-2107 ◽

Cited By ~ 13

Author(s):

Manabu Shibasaki ◽

Peter Rasmussen ◽

Niels H. Secher ◽

Craig G. Crandall

Keyword(s):

Blood Flow ◽

Skin Blood Flow ◽

Neural Control ◽

Handgrip Exercise ◽

Isometric Handgrip ◽

Isometric Handgrip Exercise

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Forearm blood flow responses to fatiguing isometric contractions in women and men

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.01136.2006 ◽

2007 ◽

Vol 293 (1) ◽

pp. H805-H812 ◽

Cited By ~ 28

Author(s):

Benjamin C. Thompson ◽

Tanvi Fadia ◽

Danny M. Pincivero ◽

Barry W. Scheuermann

Keyword(s):

Blood Flow ◽

Forearm Blood Flow ◽

Vascular Occlusion ◽

Exercise Duration ◽

Handgrip Exercise ◽

Isometric Handgrip ◽

Isometric Handgrip Exercise ◽

Target Force ◽

The Subject ◽

Voluntary Contractions

Previous studies suggest that women experience less vascular occlusion than men when generating the same relative contractile force. This study examined forearm blood flow (FBF) in women and men during isometric handgrip exercise requiring the same relative force. Thirty-eight subjects [20 women and 18 men, 22.8 ± 0.6 yrs old (means ± SE)] performed low- and moderate-force handgrip exercise on two occasions. Subjects performed five maximum voluntary contractions (MVC) before exercise to determine 20% and 50% MVC target forces. Time to task failure (TTF) was determined when the subject could not maintain force within 5% of the target force. Mean blood velocity was measured in the brachial artery with the use of Doppler ultrasonography. Arterial diameter was measured at rest and used to calculate absolute FBF (FBFa; ml/min) and relative FBF (FBFr; ml·min−1·100 ml−1). Women generated less ( P < 0.05) absolute maximal force (208 ± 10 N) than men (357 ± 17 N). The TTF was longer ( P < 0.05) at 20% MVC for women (349 ± 32 s) than for men (230 ± 23 s), but no difference between the sexes was observed at 50% MVC (women: 69 ± 5 s; men: 71 ± 8 s). FBFa and FBFr increased ( P < 0.05) from rest to TTF in both women and men during 20% and 50% MVC trials. FBFr was greater in women than in men at ≥30% TTF during 50% MVC. At exercise durations ≥60% of TTF, FBFa was lower ( P < 0.05) in women than in men during handgrip at 20% MVC. Despite the longer exercise duration for women at the lower contraction intensity, FBFr was similar between the sexes, suggesting that muscle perfusion is matched to the exercising muscle mass independent of sex.

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Influence of hand dominance on peak forearm blood flow and cardiovascular responses to isometric handgrip exercise in recreationally active racquet players

The FASEB Journal ◽

10.1096/fasebj.27.1_supplement.710.16 ◽

2013 ◽

Vol 27 (S1) ◽

Author(s):

Derek Stephen Kimmerly ◽

Lauren Hughes ◽

Lauren Quattrocchi

Keyword(s):

Blood Flow ◽

Forearm Blood Flow ◽

Cardiovascular Responses ◽

Hand Dominance ◽

Handgrip Exercise ◽

Isometric Handgrip ◽

Isometric Handgrip Exercise

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Cutaneous vasomotor responses in boys and men

Applied Physiology Nutrition and Metabolism ◽

10.1139/apnm-2018-0083 ◽

2018 ◽

Vol 43 (10) ◽

pp. 1019-1026 ◽

Cited By ~ 5

Author(s):

Gary J. Hodges ◽

Matthew C. Mueller ◽

Stephen S. Cheung ◽

Bareket Falk

Keyword(s):

Blood Flow ◽

Skin Blood Flow ◽

Local Heating ◽

Handgrip Exercise ◽

Isometric Handgrip ◽

Local Skin ◽

Doppler Flowmetry ◽

Age Related ◽

Isometric Handgrip Exercise ◽

Underlying Mechanisms

Few studies have investigated skin blood flow in children and age-related differences in the underlying mechanisms. We examined mechanisms of skin blood flow responses to local heating, postocclusive reactive hyperaemia (PORH), and isometric handgrip exercise in adult and prepubescent males, hypothesizing that skin blood flow responses would be greater in children compared with adults. We measured skin blood flow in 12 boys (age, 9 ± 1 years) and 12 men (age, 21 ± 1 years) using laser-Doppler flowmetry at rest, in response to 3-min PORH, 2-min isometric handgrip exercise, and local skin heating to 39 °C (submaximal) and 44 °C (maximal). Using wavelet analysis we assessed endothelial, neural, and myogenic activities. At rest and in response to local heating to 39 °C, children had higher skin blood flow and endothelial activity compared with men (d ≥ 1.1, p < 0.001) and similar neurogenic and myogenic activities (d < 0.2, p > 0.05). Maximal responses to 44 °C local skin heating, PORH, and isometric handgrip exercise did not differ between boys and men (all d ≤ 0.2, p > 0.05). During PORH children demonstrated greater endothelial activity compared with men (d ≥ 0.6, p < 0.05); in contrast, men had higher neurogenic activity (d = 1.0, p < 0.01). During isometric handgrip exercise there were no differences in endothelial, neurogenic, and myogenic activities (d < 0.2, p > 0.3), with boys and men demonstrating similar increases in endothelial activity and decreases in myogenic activity (d ≥ 0.8, p < 0.05). These data suggest that boys experience greater levels of skin blood flow at rest and in response to submaximal local heating compared with men, while maximal responses appear to be similar. Additionally, endothelial mediators seem to contribute more to vasodilatation in boys than in men.

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