Human arterial responses to isometric exercise: the role of the muscle metaboreflex

2007 ◽  
Vol 112 (8) ◽  
pp. 441-447 ◽  
Author(s):  
Tom S. Davies ◽  
Michael P. Frenneaux ◽  
Ross I. Campbell ◽  
Michael J. White
Keyword(s):  
Plantar Flexion ◽  
Isometric Exercise ◽  
Arterial Tree ◽  
Contralateral Limb ◽  
Post Exercise ◽  
Muscle Metaboreflex ◽  
Calf Exercise ◽  
Exercise Induced ◽  
Arterial Responses

The effects of exercise on the distensibility of large and medium-sized arteries are poorly understood, but can be attributed to a combination of local vasodilator effects of exercise opposed by sympathetic vasoconstrictor tone. We sought to examine this relationship at the conduit artery level, with particular reference to the role of the sympatho-excitatory muscle metaboreflex. The effect of maintained muscle metaboreflex activation on a previously passive or exercised limb femoral artery was investigated. A total of ten healthy volunteers performed 2 min of isometric ankle plantar-flexion at 40% MVC (maximal voluntary force), in conjunction with 2 min of either non-ischaemic isometric HG (handgrip; control condition) or IHG (ischaemic HG) at 40% MVC. IHG was followed by 2 min of PECO (post-exercise circulatory occlusion) to maintain muscle metaboreflex activation. FTPWV [femoral–tibial PWV (pulse wave velocity)] was measured in the exercised or contralateral limb at baseline and immediately following calf exercise. BP (blood pressure) and HR (heart rate) were measured continuously throughout. In the HG condition, BP and HR returned promptly to baseline post-exercise, whereas exercised leg FTPWV was decreased (less stiff) by 0.6 m/s (P<0.05) and the non-exercised leg PWV was not changed from baseline. PECO caused a sustained increase in BP, but not HR, in the IHG condition. Contralateral leg PWV increased (stiffened) during PECO by 0.9 m/s (P<0.05), whereas exercised limb FTPWV was not changed from baseline. In conclusion, muscle metaboreflex activation causes a systemic stiffening of the arterial tree, which can overcome local exercise-induced decreases in arterial PWV.

scholarly journals Human arterial responses to isometric exercise: the role of the muscle metaboreflex

2006 ◽  
Vol 20 (4) ◽  
Author(s):  
Thomas Davies ◽  
Ross Campbell ◽  
Michael Frenneaux ◽  
Michael White
Keyword(s):  
Isometric Exercise ◽  
Muscle Metaboreflex ◽  
Arterial Responses

scholarly journals Augmented Hemodynamic Responses in Obese Young Men during Dynamic Exercise: Role of the Muscle Metaboreflex

2020 ◽  
Vol 17 (19) ◽  
pp. 7321
Author(s):  
Byung-Sun Lee ◽  
Kyung-Ae Kim ◽  
Jong-Kyung Kim ◽  
Hosung Nho
Keyword(s):  
Blood Pressure ◽  
Blood Pressure Response ◽  
Cardiovascular Responses ◽  
Normal Weight ◽  
Dynamic Exercise ◽  
Handgrip Exercise ◽  
Vascular Conductance ◽  
Post Exercise ◽  
Muscle Metaboreflex

Studies found that cardiovascular responses to exercise are enhanced in individuals with obesity and are associated with a greater cardiac output (CO) response compared to normal weight controls. However, the mechanisms underlying these altered responses during dynamic exercise are not clear. We investigated whether the cardiovascular responses mediated by the muscle metaboreflex (MMR) activation are augmented in obese men during both static and dynamic exercise. Twenty males (10 obese (OG) and 10 non-obese (NOG)) were studied. Changes in CO, mean arterial pressure (MAP), and total vascular conductance (TVC) were compared between the two groups during dynamic handgrip exercise (DHE), post-exercise muscular ischemia (PEMI), and dynamic exercise corresponding to 40%, 60% and 80% workloads. Subjects completed 2 min of DHE at 30% of MVC, followed by 2 min of PEMI. MAP, CO, and TVC responses to DHE and dynamic exercise were significantly higher in OG, whereas there were no differences during PEMI. Increases in CO and MAP during mild to heavy dynamic exercise were seen in both groups, but the changes in these variables were greater in the OG. There were no significant differences in TVC between the two groups. Compared to NOG, the augmented blood pressure response to DHE and dynamic exercise in OG was associated with a greater increase in CO. Thus, the augmented CO and MAP responses were not associated with the activation of the MMR. Consequently, additional factors specific to obesity, such as the mechanoreflex, may have been involved.

Muscle cooling delays activation of the muscle metaboreflex in humans

1997 ◽  
Vol 273 (5) ◽  
pp. H2436-H2441 ◽  
Author(s):  
Chester A. Ray ◽  
Keith M. Hume ◽  
Kathryn H. Gracey ◽  
Edward T. Mahoney
Keyword(s):  
Heart Rate ◽  
Muscle Sympathetic Nerve Activity ◽  
Isometric Exercise ◽  
Voluntary Contraction ◽  
Muscle Temperature ◽  
Isometric Handgrip ◽  
Local Cooling ◽  
Muscle Metaboreflex ◽  
Muscle Cooling ◽  
Exercise Induced

Elevation of muscle temperature has been shown to increase muscle sympathetic nerve activity (MSNA) during isometric exercise in humans. The purpose of the present study was to evaluate the effect of muscle cooling on MSNA responses during exercise. Eight subjects performed ischemic isometric handgrip at 30% of maximal voluntary contraction to fatigue followed by 2 min of postexercise muscle ischemia (PEMI), with and without local cooling of the forearm. Local cooling of the forearm decreased forearm muscle temperature from 31.8 ± 0.4 to 23.1 ± 0.8°C ( P = 0.001). Time to fatigue was not different during the control and cold trials (156 ± 11 and 154 ± 5 s, respectively). Arterial pressures and heart rate were not significantly affected by muscle cooling during exercise, although heart rate tended to be higher during the second minute of exercise ( P = 0.053) during muscle cooling. Exercise-induced increases in MSNA were delayed during handgrip with local cooling compared with control. However, MSNA responses at fatigue and PEMI were not different between the two conditions. These findings suggest that muscle cooling delayed the activation of the muscle metaboreflex during ischemic isometric exercise but did not prevent its full expression during fatiguing contraction. These results support the concept that muscle temperature can play a role in the regulation of MSNA during exercise.

Exercise-Induced Nasal Obstruction in Patients with Allergic Rhinitis

1989 ◽  
Vol 3 (1) ◽  
pp. 1-4 ◽  
Author(s):  
Motofumi Ohki ◽  
Makoto Hasegawa ◽  
Akira Sakuma
Keyword(s):  
Allergic Rhinitis ◽  
Nasal Obstruction ◽  
Normal Subjects ◽  
Nasal Resistance ◽  
Post Exercise ◽  
Nasal Cycle ◽  
Exercise Period ◽  
Capacitance Vessels ◽  
Exercise Induced

Exercise-induced nasal obstruction was studied in 90 patients with allergic rhinitis and 26 normal subjects. Allergic patients as well as normal subjects showed marked decreases of nasal resistance immediately after exercise. In allergic patients, however, the total nasal resistance returned to the pre-exercise level quickly after exercise and surpassed it. Meanwhile, the total nasal resistance gradually returned to the pre-exercise level in the post-exercise period in normal subjects. The profile of the total nasal resistance changes in the allergic patients was statistically different from that in the normal subjects. As far as unilateral nasal resistance is concerned, marked increases of nasal resistance appeared 10–30 minutes after exercise in 20 of 90 allergic patients. On the contrary, this phenomenon was not found in any normal subject. This unilateral nasal obstruction, which appeared only in allergic patients, is probably due to excessive dilatation of the capacitance vessels in the nasal mucosa and considered to appear as an enhancement of the nasal cycle. In this paper, the role of the nasal cycle is discussed in relation to exercise-induced nasal obstruction.

The effect of post-exercise application of either graduated or uniform compression socks on the mitigation of delayed onset muscle soreness

2018 ◽  
Vol 89 (9) ◽  
pp. 1792-1806 ◽  
Author(s):  
Adam C McDonnell ◽  
Diane Cooper ◽  
Tinkara Mlinar ◽  
Igor B Mekjavic
Keyword(s):  
Muscle Soreness ◽  
Delayed Onset Muscle Soreness ◽  
Moderate Pain ◽  
Uniform Compression ◽  
Post Exercise ◽  
Delayed Onset ◽  
Knee Height ◽  
Calf Exercise ◽  
Exercise Induced ◽  
Calf Pain

A series of studies were conducted to test the hypothesis that compression socks (uniform or graduated compression) worn after exercise mitigate exercise-induced pain. Fifty-nine (59) participants took part in three separate exercise protocols to induce a degree of muscle soreness from low to severe. Participants wore either ankle height socks with no compression (NoCo), knee height socks with uniform (UNI) or graduated compression (GRAD) for 8 h/day following exercise. Before, immediately after and during recovery, we measured muscle strength, flexibility and the perception of pain. The three exercise protocols were as follows. (1) Hike: compared the effects of GRAD and NoCo socks following a 10-km treadmill hike with a 1000 m ascent and descent. (2) Trail Run: compared the effect of GRAD and UNI following a 14-km trail run with 250 m ascent and descent. (3) Calf Exercise: compared the effect of GRAD and UNI socks with a predominately eccentric calf exercise. GRAD socks significantly mitigated the perception of calf pain compared to NoCo (Hike). The UNI socks were superior to the GRAD socks in mitigating the perception of pain during recovery in the Trail Run. No statistical difference was noted between UNI and GRAD socks after the Calf Exercise. Compression socks mitigated the perception of calf muscle pain (Hike trial), with UNI providing more benefit compared to GRAD socks (Trail Run trial). No differences between the UNI and GRAD socks were observed in the Calf Exercise trial. Compression socks aid in the perception of recovery following low to moderate pain from delayed onset muscle soreness.

Exercise-Induced Fibrinolysis – Fact or Fiction?

1982 ◽  
Vol 48 (02) ◽  
pp. 201-203 ◽  
Author(s):  
N A Marsh ◽  
P J Gaffney
Keyword(s):  
Plasminogen Activator ◽  
Degradation Products ◽  
Coagulation Factors ◽  
Vascular Wall ◽  
Strenuous Exercise ◽  
Fibrin Degradation Products ◽  
Real Increase ◽  
Exercise Induced ◽  
Male Subjects

SummaryThe effect of strenuous exercise on the fibrinolytic and coagulation mechanisms was examined in six healthy male subjects. Five min bicycle exercise at a work-rate of 800 to 1200 kpm. min−1 produced an abrupt increase in plasma plasminogen activator levels which disappeared after 90 min. However, there was no change in early or late fibrin degradation products nor was there a change in fibrinopeptide A levels or βthromboglobulin levels after exercise although activated partial thromboplastin times were significantly shortened. It is concluded that strenuous exercise does not produce any real increase in fibrinogen-fibrin conversion nor any real increase in the breakdown of these proteins. The role of exercise-induced release of plasminogen activator remains unclear, but probably helps to maintain plasma levels in a discontinuous manner concurrently with the continuous low-level secretion from the vascular wall. The shortening of partial thromboplastin time may be due to the raised levels of plasminogen activator changing the activation state of other coagulation factors.

Role of the sympathoadrenal system in exercise-induced inhibition of insulin secretion. Effects of islet transplantation

Diabetes ◽  
1995 ◽  
Vol 44 (5) ◽  
pp. 565-571 ◽  
Author(s):  
H. Houwing ◽  
K. M. Frankel ◽  
J. H. Strubbe ◽  
P. T. van Suylichem ◽  
A. B. Steffens
Keyword(s):  
Insulin Secretion ◽  
Islet Transplantation ◽  
Sympathoadrenal System ◽  
Exercise Induced

scholarly journals Isometric Handgrip Exercise Training Improves Spirometric Parameters and Pulmonary Capacity

2021 ◽  
Vol 28 (3) ◽  
pp. 328-338
Author(s):  
Ogbutor Udoji Godsday ◽  
Nwangwa Eze Kingsley ◽  
Nwogueze Bartholomew Chukwuebuka ◽  
Chukwuemeka Ephraim ◽  
Ezunu Emmanuel ◽  
...  
Keyword(s):  
Pulmonary Function ◽  
Isometric Exercise ◽  
Handgrip Exercise ◽  
Isometric Handgrip ◽  
Post Exercise ◽  
Significant Difference ◽  
Isometric Handgrip Exercise ◽  
Group 3 ◽  
Group 2 ◽  
Group 1

Decline in normal physiological pulmonary function has been attributed to premorbid conditions such as prehypertension. Research evidence suggests that physical activity reduces age-related decline in pulmonary function and improves the efficiency of the lungs in prehypertensive patients. However, there is a scarcity of data evidence relating to isometric exercise and pulmonary function. Furthermore, the interrelationship between the intensity and duration of isometric exercise and pulmonary function in these patients is still uncertain. Therefore, this study was undertaken to investigate the effect of isometric handgrip exercise on pulmonary function capacity in adults with prehypertension. To determine the effectiveness of isometric handgrip exercise on pulmonary function capacity in adults with prehypertension. A quasi experiment using a pre- and post-exercise method was carried out in two out-patients hospital settings. The sample comprised 192 sedentary pre-hypertensive subjects, aged between 30–50 years, that were randomly distributed into three groups of 64 participants each. The subjects performed, for 24 consecutive days, an isometric handgrip exercise at 30% Maximum Voluntary Contraction (M.V.C.). At the end of the 24 days, group one (GP1) discontinued, while group two (GP2) continued the exercise protocol for another 24 consecutive days and group three (GP3) continued with the exercise protocol for another 24 consecutive days but at 50% M.V.C. Determinants of lung function (outcomes) were Forced Expiratory Volume in 1 s (FEV1), Forced Vital Capacity (FVC), FEV1/FVC Ratio and Peak Expiratory Flow Rate (PEFR). The study shows that there was no statistically significant difference in the pre- and post-exercise outcomes for FEV1, FVC, FEV1/FVC Ratio and PEFR after 24 days for group 1. In group 2, there was a statistically significant difference in the FVC [(mean = 0.12 ± 0.12), (p = 0.002)], FEV1 [(mean = 0.15 ± 0.17), (p = 0.003)] and PEF [(mean = 0.85 ± 0.35), (p = 0.001)] after 48 days. In group 3, there was a statistically significant difference (p = 0.001) in all the outcomes assessed after 48 days. There was a between groups difference in favour of group 2 compared with group 1 for outcomes of FEV1 [(mean = 0.142 ± 0.68), (p = 0.005)] and PEF [(mean = 0.83 ± 0.19), (p = 0.0031)]. There was statistically significant difference in favour of group 3 compared to group 2, by increasing the exercise intensity from 30% to 50% M.V.C., for outcomes of FVC [mean change = 0.10 ± 0.052), (p = 0.005)], FEV1/FVC [mean change = 3.18 ± 0.75), (p = 0.017)] and PEF [(mean change = 0.86 ± 0.35), (p = 0.001)] after 48 days. Isometric handgrip exercise (after 48 days at 30% to 50% M.V.C.) improves outcomes of pulmonary function capacity in adults with prehypertension. Meanwhile, duration and/or increase in intensity of the isometric effort significantly contributed to the affects attained.

scholarly journals From Exercise to Cognitive Performance: Role of Irisin

2021 ◽  
Vol 11 (15) ◽  
pp. 7120
Author(s):  
Mirko Pesce ◽  
Irene La Fratta ◽  
Teresa Paolucci ◽  
Alfredo Grilli ◽  
Antonia Patruno ◽  
...  
Keyword(s):  
The Elderly ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Beneficial Effects ◽  
General Exercise ◽  
Fibronectin Type Iii ◽  
Exercise Induced ◽  
Fibronectin Type Iii Domain ◽  
The Brain

The beneficial effects of exercise on the brain are well known. In general, exercise offers an effective way to improve cognitive function in all ages, particularly in the elderly, who are considered the most vulnerable to neurodegenerative disorders. In this regard, myokines, hormones secreted by muscle in response to exercise, have recently gained attention as beneficial mediators. Irisin is a novel exercise-induced myokine, that modulates several bodily processes, such as glucose homeostasis, and reduces systemic inflammation. Irisin is cleaved from fibronectin type III domain containing 5 (FNDC5), a transmembrane precursor protein expressed in muscle under the control of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α). The FNDC5/irisin system is also expressed in the hippocampus, where it stimulates the expression of the neurotrophin brain-derived neurotrophic factor in this area that is associated with learning and memory. In this review, we aimed to discuss the role of irisin as a key mediator of the beneficial effects of exercise on synaptic plasticity and memory in the elderly, suggesting its roles within the main promoters of the beneficial effects of exercise on the brain.

Sign in / Sign up

Export Citation Format

Share Document