Changes of muscle oxygenation and blood lactate concentration of swimming athletes during graded incremental exercise

Near-infrared spectroscopy (NIRS) could allow insights into controversial issues related to blood lactate concentration ([La]b) increases at submaximal workloads (w˙). We combined, on five well-trained subjects [mountain climbers; peak O2 consumption (V˙o 2peak), 51.0 ± 4.2 (SD) ml ⋅ kg−1 ⋅ min−1] performing incremental exercise on a cycle ergometer (30 W added every 4 min up to voluntary exhaustion), measurements of pulmonary gas exchange and earlobe [La]b with determinations of concentration changes of oxygenated Hb (Δ[O2Hb]) and deoxygenated Hb (Δ[HHb]) in the vastus lateralis muscle, by continuous-wave NIRS. A “point of inflection” of [La]b vs.w˙ was arbitrarily identified at the lowest [La]b value which was >0.5 mM lower than that obtained at the following w˙. Total Hb volume (Δ[O2Hb + HHb]) in the muscle region of interest increased as a function ofw˙ up to 60–65% ofV˙o 2 peak, after which it remained unchanged. The oxygenation index (Δ[O2Hb − HHb]) showed an accelerated decrease from 60– 65% ofV˙o 2 peak. In the presence of a constant total Hb volume, the observed Δ[O2Hb − HHb] decrease indicates muscle deoxygenation (i.e., mainly capillary-venular Hb desaturation). The onset of muscle deoxygenation was significantly correlated ( r 2 = 0.95; P < 0.01) with the point of inflection of [La]bvs. w˙, i.e., with the onset of blood lactate accumulation. Previous studies showed relatively constant femoral venous[Formula: see text] levels at w˙ higher than ∼60% of maximal O2consumption. Thus muscle deoxygenation observed in the present study from 60–65% ofV˙o 2 peak could be attributed to capillary-venular Hb desaturation in the presence of relatively constant capillary-venular[Formula: see text] levels, as a consequence of a rightward shift of the O2Hb dissociation curve determined by the onset of lactic acidosis.

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Acute Effect of Repeated Sprint Exercise With Blood Flow Restriction During Rest Periods on Muscle Oxygenation

Frontiers in Physiology ◽

10.3389/fphys.2021.665383 ◽

2021 ◽

Vol 12 ◽

Author(s):

Chihiro Kojima ◽

Keiichi Yamaguchi ◽

Hiroto Ito ◽

Nobukazu Kasai ◽

Olivier Girard ◽

...

Keyword(s):

Blood Lactate ◽

Power Output ◽

Near Infrared ◽

Vastus Lateralis ◽

Lactate Concentration ◽

Blood Lactate Concentration ◽

Rest Period ◽

Muscle Oxygenation ◽

Rest Periods ◽

Repeated Cycling

PurposeThis study aimed to examine the effect of applying BFR during rest periods of repeated cycling sprints on muscle oxygenation.MethodsSeven active males performed 5 × 10-s maximal pedaling efforts with 40-s passive rest, with or without BFR application during rest period. BFR was applied for 30 s between sprints (between 5 and 35 s into rest) through a pneumatic pressure cuff inflated at 140 mmHg. Vastus lateralis muscle oxygenation was monitored using near-infrared spectroscopy. In addition, blood lactate concentration and heart rate were also evaluated.ResultsThe BFR trial showed significantly lower oxyhemoglobin (oxy-Hb) and tissue saturation (StO2) levels than the CON trial (P < 0.05). However, power output and blood lactate concentration did not significantly differ between the two trials (P > 0.05).ConclusionApplying BFR during rest periods of repeated cycling sprints decreased muscle oxygenation of active musculature, without interfering with power output during sprints.

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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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RELATIONSHIPS BETWEEN RECALL OF PERCEIVED EXERTION AND BLOOD LACTATE CONCENTRATION IN A JUDO COMPETITION

Perceptual and Motor Skills ◽

10.2466/pms.92.3.1139-1148 ◽

2001 ◽

Vol 92 (3) ◽

pp. 1139 ◽

Cited By ~ 7

Author(s):

MIGUEL ANGEL SERRANO

Keyword(s):

Blood Lactate ◽

Perceived Exertion ◽

Lactate Concentration ◽

Blood Lactate Concentration

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Effect of PEMF on Muscle Oxygenation during Cycling: A Single-Blind Controlled Pilot Study

Applied Sciences ◽

10.3390/app11083624 ◽

2021 ◽

Vol 11 (8) ◽

pp. 3624

Author(s):

Aurelio Trofè ◽

Milena Raffi ◽

David Muehsam ◽

Andrea Meoni ◽

Francesco Campa ◽

...

Keyword(s):

Blood Lactate ◽

Slow Component ◽

Local Level ◽

Lactate Concentration ◽

Oxygenation Index ◽

State Level ◽

Acute Effect ◽

Primary Component ◽

Muscle Oxygenation ◽

Oxygen Kinetics

Pulsed electromagnetic fields (PEMFs) are used as non-invasive tools to enhance microcirculation and tissue oxygenation, with a modulatory influence on the microvasculature. This study aimed to measure the acute effect of PEMF on muscle oxygenation and its influence on pulmonary oxygen kinetics during exercise. Eighteen male cyclists performed, on different days, a constant-load exercise in both active (ON) and inactive (OFF) PEMF stimulations while deoxyhemoglobin and pulmonary oxygen kinetics, total oxygenation index, and blood lactate were collected. PEMF enhanced muscle oxygenation, with higher values of deoxyhemoglobin both at the primary component and at the steady-state level. Moreover, PEMF accelerated deoxyhemoglobin on-transition kinetic, with a shorter time delay, time constant, and mean response time than the OFF condition. Lactate concentration was higher during stimulation. No differences were found for total oxygenation index and pulmonary oxygen kinetics. Local application of a precise PEMF stimulation can increase the rate of the muscle O2 extraction and utilization. These changes were not accompanied by faster oxygen kinetics, reduced oxygen slow component, or reduced blood lactate level. It seems that oxygen consumption is more influenced by exercise involving large muscle mass like cycling, whereas PEMF might only act at the local level.

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Effects of cocaine on incremental treadmill exercise in horses

Journal of Applied Physiology ◽

10.1152/jappl.1993.75.6.2727 ◽

1993 ◽

Vol 75 (6) ◽

pp. 2727-2733 ◽

Cited By ~ 10

Author(s):

K. H. McKeever ◽

K. W. Hinchcliff ◽

D. F. Gerken ◽

R. A. Sams

Keyword(s):

Right Ventricular ◽

Blood Lactate ◽

Venous Blood ◽

Lactate Concentration ◽

Blood Lactate Concentration ◽

Ventricular Pressure ◽

Mixed Venous Blood ◽

Work Intensity ◽

Venous Blood Lactate ◽

Mixed Venous

Four mature horses were used to test the effects of two doses (50 and 200 mg) of intravenously administered cocaine on hemodynamics and selected indexes of performance [maximal heart rate (HRmax), treadmill velocity at HRmax, treadmill velocity needed to produce a blood lactate concentration of 4 mmol/l, maximal mixed venous blood lactate concentration, maximal treadmill work intensity, and test duration] measured during an incremental treadmill test. Both doses of cocaine increased HRmax approximately 7% (P < 0.05). Mean arterial pressure was 30 mmHg greater (P < 0.05) during the 4- to 7-m/s steps of the exercise test in the 200-mg trial. Neither dose of cocaine had an effect on the responses to exertion of right atrial pressure, right ventricular pressure, or maximal change in right ventricular pressure over time. Maximal mixed venous blood lactate concentration increased 41% (P < 0.05) with the 50-mg dose and 75% (P < 0.05) with the 200-mg dose during exercise. Administration of cocaine resulted in decreases (P < 0.05) in the treadmill velocity needed to produce a blood lactate concentration of 4 mmol/l from 6.9 +/- 0.5 and 6.8 +/- 0.9 m/s during the control trials to 4.4 +/- 0.1 m/s during the 200-mg cocaine trial. Cocaine did not alter maximal treadmill work intensity (P > 0.05); however, time to exhaustion increased by approximately 92 s (15%; P < 0.05) during the 200-mg trial.(ABSTRACT TRUNCATED AT 250 WORDS)

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Peripheral Modulators of the Central Fatigue Development and Their Relationship with Athletic Performance in Jumper Horses

Animals ◽

10.3390/ani11030743 ◽

2021 ◽

Vol 11 (3) ◽

pp. 743

Author(s):

Francesca Arfuso ◽

Claudia Giannetto ◽

Elisabetta Giudice ◽

Francesco Fazio ◽

Michele Panzera ◽

...

Keyword(s):

Blood Lactate ◽

Athletic Performance ◽

Lactate Concentration ◽

Indirect Evidence ◽

Blood Lactate Concentration ◽

Central Fatigue ◽

Serotoninergic System ◽

Stressful Situation ◽

Passive Behavior ◽

Fatigue Development

The current study aimed to investigate whether peripheral modulators of serotoninergic function and neurohumoral factors’ changes in athletic horses during an official jumping competition, and to evaluate their relationship with the physical performance of competing horses. From 7 Italian Saddle mares (6–9 years; mean body weight 440 ± 15 kg), performing the same standardized warm-up and jumping course during an official class, heart rate (HR) was monitored throughout the competition. Rectal temperature (RT) measurement, blood lactate and glucose concentration, serum tryptophan, leucine, valine, the tryptophan/branched-chain amino-acids ratio (Try/BCAAs), dopamine, prolactin, and non-esterified fatty acids (NEFAs) were assessed before the exercise event (T0), at the end of the competition stage (5 min ± 10 s following the cessation of the exercise, TPOST5), and 30 min after the end of competition (TPOST30). Highest HR values were recorded during the course and at the outbound (p < 0.0001); blood lactate concentration and RT increased after exercise with respect to the rest condition (p < 0.0001). Lower leucine and valine levels (p < 0.01), and higher tryptophan, Try/BCAAs ratio, and NEFAs values were found at TPOST5 and TPOST30 with respect to T0 (p < 0.0001). A higher prolactin concentration was found at TPOST5 and TPOST30 compared to T0 (p < 0.0001), whereas dopamine showed decreased values after exercise compared to rest (p < 0.0001). Statistically significant correlations among the peripheral indices of serotoninergic function, neurohumoral factors, and athletic performance parameters were found throughout the monitoring period. The findings provide indirect evidence that the serotoninergic system may be involved in fatigue during jumper exercise under a stressful situation, such as competition, in which, in addition to physical effort, athletic horses exhibit more passive behavior.

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