The relation between blood lactate and ammonia in ischemic handgrip exercise

This study aimed to determine the importance of repeated increases in blood flow to conduit artery adaptation, using an exercise-independent repeated episodic stimulus. Recent studies suggest that exercise training improves vasodilator function of conduit arteries via shear stress-mediated mechanisms. However, exercise is a complex stimulus that may induce shear-independent adaptations. Nine healthy men immersed their forearms in water at 42°C for three 30-min sessions/wk across 8 wk. During each session, a pneumatic pressure cuff was inflated around one forearm to unilaterally modulate heating-induced increases in shear. Forearm heating was associated with an increase in brachial artery blood flow ( P < 0.001) and shear rate ( P < 0.001) in the uncuffed forearm; this response was attenuated in the cuffed limb ( P < 0.005). Repeated episodic exposure to bilateral heating induced an increase in endothelium-dependent vasodilation in response to 5-min ischemic ( P < 0.05) and ischemic handgrip exercise ( P < 0.005) stimuli in the uncuffed forearm, whereas the 8-wk heating intervention did not influence dilation to either stimulus in the cuffed limb. Endothelium-independent glyceryl trinitrate responses were not altered in either limb. Repeated heating increases blood flow to levels that enhance endothelium-mediated vasodilator function in humans. These findings reinforce the importance of the direct impacts of shear stress on the vascular endothelium in humans.

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DOES NITRIC OXIDE-MEDIATED, SYMPATHETIC VASODILATION OCCUR DURING ISCHEMIC HANDGRIP EXERCISE IN HUMANS? 1042

Medicine & Science in Sports & Exercise ◽

10.1097/00005768-199605001-01040 ◽

1996 ◽

Vol 28 (Supplement) ◽

pp. 175

Author(s):

K A Engelke ◽

N M Dietz ◽

R T Fix ◽

T T Samuel ◽

M M Williams ◽

...

Keyword(s):

Nitric Oxide ◽

Handgrip Exercise ◽

Ischemic Handgrip Exercise ◽

Exercise In Humans

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Relationship between RPE and Blood Lactate after Fatiguing Handgrip Exercise in Taekwondo and Sedentary Subjects

Biology and Medicine ◽

10.4172/0974-8369.1000s3008 ◽

2015 ◽

Vol s3 ◽

Cited By ~ 5

Author(s):

Messina G ◽

Valenzano A

Keyword(s):

Blood Lactate ◽

Handgrip Exercise ◽

Sedentary Subjects

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Blood pressure predicts endothelial function and the effects of ethinyl estradiol exposure in young women

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00188.2018 ◽

2018 ◽

Vol 315 (4) ◽

pp. H925-H933 ◽

Cited By ~ 5

Author(s):

Tessa E. Adler ◽

Charlotte W. Usselman ◽

Akira Takamata ◽

Nina S. Stachenfeld

Keyword(s):

Blood Pressure ◽

Endothelial Dysfunction ◽

Endothelial Function ◽

Young Women ◽

Pressure Range ◽

Ethinyl Estradiol ◽

Flow Mediated Dilation ◽

Handgrip Exercise ◽

Endothelial Impairment ◽

Ischemic Handgrip Exercise

Hypertension, obesity, and endothelial function predict cardiovascular disease in women, and these factors are interrelated. We hypothesized that hypertension and obesity are associated with endothelial dysfunction in young women and that short-term ethinyl estradiol exposure mitigates this dysfunction. We examined flow-mediated dilation (FMD) responses before and during 7 days of oral ethinyl estradiol (30 µg/day) in 19 women (25 ± 5, 18–35 yr). We divided our sample into two groups based on two criteria: blood pressure and obesity. Women were divided into normal blood pressure (NBP; mean arterial pressure range: 78–91 mmHg, n = 7) and high blood pressure (HBP; mean arterial pressure range: 95–113 mmHg, n = 9) groups. We also stratified our subjects by body composition (lean: 18–31%, n = 8; obese: 38–59%, n = 9). We evaluated brachial FMD after two distinct shear stress stimuli: occlusion alone and occlusion with ischemic handgrip exercise. Obesity was unrelated to both FMD responses. Before ethinyl estradiol administration, the HBP group had blunted ischemic exercise responses relative to the NBP group (8.0 ± 3.5 vs. 12.3 ± 3.2%, respectively, P = 0.05). However, during ethinyl estradiol administration, ischemic exercise responses increased in the HBP group (12.8 ± 6.1%, P = 0.04) but decreased in the NBP group (5.6 ± 2.4%, P = 0.01). Standard FMD did not reveal differences between groups. In summary, 1) moderate HBP predicted endothelial impairment, 2) ethinyl estradiol administration had divergent effects on FMD in women with NBP versus HBP, and 3) enhanced FMD (ischemic handgrip exercise) revealed differences in endothelial function, whereas standard FMD (occlusion alone) did not. NEW & NOTEWORTHY We are the first to show that mild hypertension is a stronger predictor of endothelial dysfunction than obesity in healthy women without overt cardiovascular dysfunction. Importantly, the standard 5-min flow-mediated vasodilation stimulus did not detect endothelial dysfunction in our healthy population; only an enhanced ischemic handgrip exercise shear stress stimulus detected endothelial impairment. Estradiol administration increased flow-mediated dilation in women with high blood pressure, so it may be a therapeutic intervention to improve endothelial function.

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WISE 2005: stroke volume changes contribute to the pressor response during ischemic handgrip exercise in women

Journal of Applied Physiology ◽

10.1152/japplphysiol.01334.2006 ◽

2007 ◽

Vol 103 (1) ◽

pp. 228-233 ◽

Cited By ~ 66

Author(s):

J. K. Shoemaker ◽

L. Mattar ◽

P. Kerbeci ◽

S. Trotter ◽

P. Arbeille ◽

...

Keyword(s):

Blood Pressure ◽

Stroke Volume ◽

Portal Vein ◽

Pressor Response ◽

Muscle Sympathetic Nerve Activity ◽

Handgrip Exercise ◽

Isometric Handgrip ◽

Arterial Blood ◽

Vein Diameter ◽

Ischemic Handgrip Exercise

The mechanism of the pressor response to small muscle mass (e.g., forearm) exercise and during metaboreflex activation may include elevations in cardiac output (Q̇) or total peripheral resistance (TPR). Increases in Q̇ must be supported by reductions in visceral venous volume to sustain venous return as heart rate (HR) increases. Therefore, this study tested the hypothesis that increases in Q̇, supported by reductions in splanchnic volume (portal vein constriction), explain the pressor response during handgrip exercise and metaboreflex activation. Seventeen healthy women performed 2 min of static ischemic handgrip exercise and 2 min of postexercise circulatory occlusion (PECO) while HR, stroke volume and superficial femoral artery flow (Doppler), blood pressure (Finometer), portal vein diameter (ultrasound imaging), and muscle sympathetic nerve activity (MSNA; microneurography) were measured followed by the calculation of Q̇, TPR, and leg vascular resistance (LVR). Compared with baseline, mean arterial blood pressure (MAP) ( P < 0.001) and Q̇ ( P < 0.001) both increased in each minute of exercise accompanied by a ∼5% reduction in portal vein diameter ( P < 0.05). MAP remained elevated during PECO, whereas Q̇ decreased below exercise levels. MSNA was elevated above baseline during the second minute of exercise and through the PECO period ( P < 0.05). Neither TPR nor LVR was changed from baseline during exercise and PECO. The data indicate that the majority of the blood pressure response to isometric handgrip exercise in women was due to mobilization of central blood volume and elevated stroke volume and Q̇ rather than elevations in TVR or LVR resistance.

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Effects of Moderate Dietary Manipulations on Swim Performance and on Blood Lactate-Swimming Velocity Curves

International Journal of Sports Medicine ◽

10.1055/s-1999-970271 ◽

1999 ◽

Vol 20 (02) ◽

pp. 93-97 ◽

Cited By ~ 1

Author(s):

T. Reilly ◽

V. Woodbridge

Keyword(s):

Blood Lactate ◽

Swimming Velocity ◽

Swim Performance

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The influence of execution speed on blood lactate concentration in strength training protocol in bench press exercise

Revista Brasileira de Fisiologia do Exercício ◽

10.33233/rbfe.v19i1.3990 ◽

2020 ◽

Vol 19 (1) ◽

pp. 32

Author(s):

Gustavo Taques Marczynski ◽

Luís Carlos Zattar Coelho ◽

Leonardo Emmanuel De Medeiros Lima ◽

Rodrigo Pereira Da Silva ◽

Dilmar Pinto Guedes Jr ◽

...

Keyword(s):

Strength Training ◽

Blood Lactate ◽

Bench Press ◽

Lactate Concentration ◽

Blood Lactate Concentration ◽

The Third ◽

Fast Speed ◽

Work Volume ◽

Execution Speed ◽

Training Protocol

The aim of this study was to analyze the influence of two velocities of execution relative to blood lactate concentration in strength training exercise until the momentary concentric failure. Fifteen men (29.1 ± 5.9 years), trained, participated in the experiment. The volunteers performed three bench press sessions, with an interval of 48 hours between them. At the first session, individuals determined loads through the 10-12 RMs test. In the following two sessions, three series with 90 seconds of interval were performed, in the second session slow execution speed (cadence 3030) and later in the third session fast speed (cadence 1010). For statistical analysis, the Student-T test was used for an independent sample study and considered the value of probability (p) ≤ 0.05 statistically significant. By comparing the number of repetitions and time under tension of the two runs, all series compared to the first presented significant reductions (p < 0.05). The total work volume was higher with the fast speed (p < 0.05). The study revealed that rapid velocities (cadence 1010) present a higher concentration of blood lactate when compared to slow runs (cadence 3030). The blood lactate concentration, in maximum repetitions, is affected by the speed of execution.Keywords: resistance training, cadence, blood lactate.

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Caffeine supplementation for 4-day, followed by acute ingestion, did not impact triathlete output power after submaximal intensity exercise

Revista Brasileira de Fisiologia do Exercício ◽

10.33233/rbfe.v18i3.3230 ◽

2019 ◽

Vol 18 (3) ◽

pp. 118

Author(s):

Anderson Pontes Morales ◽

Felipe Sampaio-Jorge ◽

Thiago Barth ◽

Alessandra Alegre De Matos ◽

Luiz Felipe Da Cruz Rangel ◽

...

Keyword(s):

Blood Lactate ◽

Output Power ◽

Body Mass ◽

Effect Size ◽

Power Output ◽

Anaerobic Power ◽

Lactate Concentration ◽

Wingate Test ◽

Large Effect Size ◽

Acute Ingestion

Introduction: The aim of this study was to test the hypothesis that caffeine supplementation (6 mg·kg-1 body mass) for 4-days, followed by acute intake, would impact five male triathletes output power after performed submaximal intensity exercise. Methods: This was a randomized, double-blind, placebo-controlled crossover study, placebo (4-day) - placebo (acute) PP, placebo (4-days) -caffeine (acute) PC, and caffeine (4-day) - caffeine (acute) CC. Participants abstained from dietary caffeine sources for 4 days and ingested capsules containing either placebo or caffeine (6 mg.kg-1 body mass day in one absorption). The acute trials the capsules containing placebo or caffeine (6 mg.kg-1 body mass day in one absorption) were ingested 60min before completing exercise in a treadmill for 40min (80% VO2max) and to perform the Wingate test. Results: Blood lactate was determined before, 60min after ingestion, and immediately after the exercise on the treadmill, the Wingate test, and after the recovery (10-min). CC and PC trials did not change the cardiopulmonary variables (P>0.05) and the anaerobic power variables (peak/mean power output and fatigue index) (P>0.05). The PC trial compared with PP promoted improvements in the curve power output in 2 sec by 31.19% (large effect-size d = 1.08; P<0.05) and 3 sec by 20% (large effect-size d = 1.19; P<0.05). A 10min recovery was not sufficient to reduce blood lactate concentration in the PC trial compared with PP (PC, 13.73±2.66 vs. PP, 10.26±1.60 mmol.L-1; P<0.05, respectively) (P<0.05). Conclusion: In conclusion, these results indicate that caffeine supplementation (6 mg·kg-1 body mass) for 4 days, followed by acute ingestion, did not impact the triathletes output power after performed submaximal intensity exercise. Nutritional interventions may help researchers and athletes to adapt strategies for manipulating caffeine use.Key-words: caffeine metabolism, Wingate test, blood lactate, performance.

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Efficacy of Near-Infrared Spectrometry for Monitoring the Cerebral Effects of Severe Dilutional Anemia

The Heart Surgery Forum ◽

10.1532/hsf98.2013293 ◽

2014 ◽

Vol 17 (3) ◽

pp. 154 ◽

Cited By ~ 10

Author(s):

Arıtürk Cem ◽

Ustalar Serpil ◽

Toraman Fevzi ◽

Ökten Murat ◽

Güllü Ümit ◽

...

Keyword(s):

Blood Flow ◽

Cardiac Surgery ◽

Blood Lactate ◽

Near Infrared ◽

Bypass Graft ◽

Blood Gas Analysis ◽

Gas Analysis ◽

Infrared Spectrometry ◽

Control Group ◽

Near Infrared Spectrometry

Introduction: Clear guidelines for red cell transfusion during cardiac surgery have not yet been established. The current focus on blood conservation during cardiac surgery has increased the urgency to determine the minimum safe hematocrit for these patients. The aim of this study was to determine whether monitoring of cerebral regional oxygen saturation (rSO2) via near-infrared spectrometry (NIRS) is effective for assessing the cerebral effects of severe dilutional anemia during elective coronary arterial bypass graft surgery (CABG).Methods: The prospective observational study involved patients who underwent cerebral rSO2 monitoring by NIRS during elective isolated first-time CABG: an anemic group (N=15) (minimum Hemoglobin (Hb) N=15) (Hb >8 g/dL during CPB). Mean arterial pressure (MAP), pump blood flow, blood lactate level, pCO2, pO2 at five time points and cross-clamp time, extracorporeal circulation time were recorded for each patient. Group results statistically were compared.Results: The anemic group had significantly lower mean preoperative Hb than the control group (10.3 mg/dL versus 14.2 mg/dL; P = .001). The lowest Hb levels were observed in the hypothermic period of CPB in the anemic group. None of the controls exhibited a >20% decrease in cerebral rSO2. Eleven (73.3%) of the anemic patients required an increase in pump blood flow to raise their cerebral rSO2.Conclusions: In this study, the changes in cerebral rSO2 in the patients with low Hb were within acceptable limits, and this was in concordance with the blood lactate levels and blood-gas analysis. It can be suggested that NIRS monitoring of cerebral rSO2 can assist in decision making related to blood transfusion and dilutional anemia during CPB.

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