scholarly journals Exercise-Induced Elevated BDNF Level Does Not Prevent Cognitive Impairment Due to Acute Exposure to Moderate Hypoxia in Well-Trained Athletes

2020 ◽  
Vol 21 (15) ◽  
pp. 5569 ◽  
Author(s):  
Zofia Piotrowicz ◽  
Małgorzata Chalimoniuk ◽  
Kamila Płoszczyca ◽  
Miłosz Czuba ◽  
Józef Langfort
Keyword(s):  
Acute Hypoxia ◽  
Negative Effects ◽  
Positive Effects ◽  
Hypoxic Conditions ◽  
Acute Elevation ◽  
Psychomotor Tasks ◽  
Exercise Induced ◽  
Response To Exercise ◽  
Cognition Impairment ◽  
The Brain

Exposure to acute hypoxia causes a detrimental effect on the brain which is also manifested by a decrease in the ability to perform psychomotor tasks. Conversely, brain-derived neurotrophic factor (BDNF), whose levels are elevated in response to exercise, is a well-known factor in improving cognitive function. Therefore, the aim of our study was to investigate whether the exercise under hypoxic conditions affects psychomotor performance. For this purpose, 11 healthy young athletes performed a graded cycloergometer exercise test to volitional exhaustion under normoxia and acute mild hypoxia (FiO2 = 14.7%). Before, immediately after exercise and after a period of recovery, choice reaction time (CRT) and number of correct reactions (NCR) in relation to changes in serum BDNF were examined. Additionally, other selected factors which may modify BDNF production, i.e., cortisol (C), nitrite, catecholamines (adrenalin-A, noradrenaline-NA, dopamine-DA, serotonin-5-HT) and endothelin-1 (ET-1), were also measured. Exercise in hypoxic conditions extended CRT by 13.8% (p < 0.01) and decreased NCR (by 11.5%) compared to rest (p < 0.05). During maximal workload, NCR was lower by 9% in hypoxia compared to normoxia (p < 0.05). BDNF increased immediately after exercise in normoxia (by 29.3%; p < 0.01), as well as in hypoxia (by 50.0%; p < 0.001). There were no differences in BDNF between normoxia and hypoxia. Considering the fact that similar levels of BDNF were seen in both conditions but cognitive performance was suppressed in hypoxia, acute elevation of BDNF did not compensate for hypoxia-induced cognition impairment. Moreover, neither potentially negative effects of C nor positive effects of A, DA and NO on the brain were observed in our study.

scholarly journals Diffusion tensor-MRI detects exercise-induced neuroplasticity in the hippocampal microstructure in mice

2020 ◽  
Vol 5 (2) ◽  
pp. 147-159
Author(s):  
Mohammad R. Islam ◽  
Renhao Luo ◽  
Sophia Valaris ◽  
Erin B. Haley ◽  
Hajime Takase ◽  
...  
Keyword(s):  
Animal Studies ◽  
Wheel Running ◽  
Diffusion Tensor ◽  
Hippocampal Volume ◽  
Mri Scans ◽  
Oligodendrocyte Precursor ◽  
Exercise Induced ◽  
Response To Exercise ◽  
The Brain

Background: Despite considerable research on exercise-induced neuroplasticity in the brain, a major ongoing challenge in translating findings from animal studies to humans is that clinical and preclinical settings employ very different techniques. Objective: Here we aim to bridge this divide by using diffusion tensor imaging MRI (DTI), an advanced imaging technique commonly applied in human studies, in a longitudinal exercise study with mice. Methods: Wild-type mice were exercised using voluntary free-wheel running, and MRI scans were at baseline and after four weeks and nine weeks of running. Results: Both hippocampal volume and fractional anisotropy, a surrogate for microstructural directionality, significantly increased with exercise. In addition, exercise levels correlated with effect size. Histological analysis showed more PDGFRα+ oligodendrocyte precursor cells in the corpus callosum of running mice. Conclusions: These results provide compelling in vivo support for the concept that similar adaptive changes occur in the brains of mice and humans in response to exercise.

scholarly journals AltitudeOmics: on the consequences of high-altitude acclimatization for the development of fatigue during locomotor exercise in humans

2013 ◽  
Vol 115 (5) ◽  
pp. 634-642 ◽  
Author(s):  
Markus Amann ◽  
Stuart Goodall ◽  
Rosie Twomey ◽  
Andrew W. Subudhi ◽  
Andrew T. Lovering ◽  
...  
Keyword(s):  
High Altitude ◽  
Muscle Fatigue ◽  
Muscle Activation ◽  
Acute Hypoxia ◽  
Central Fatigue ◽  
Constant Load ◽  
Peripheral Fatigue ◽  
Substantial Impact ◽  
Hypoxic Conditions ◽  
Exercise Induced

The development of muscle fatigue is oxygen (O2)-delivery sensitive [arterial O2 content (CaO2) × limb blood flow ( QL)]. Locomotor exercise in acute hypoxia (AH) is, compared with sea level (SL), associated with reduced CaO2 and exaggerated inspiratory muscle work (Winsp), which impairs QL, both of which exacerbate fatigue individually by compromising O2 delivery. Since chronic hypoxia (CH) normalizes CaO2 but exacerbates Winsp, we investigated the consequences of a 14-day exposure to high altitude on exercise-induced locomotor muscle fatigue. Eight subjects performed the identical constant-load cycling exercise (138 ± 14 W; 11 ± 1 min) at SL (partial pressure of inspired O2, 147.1 ± 0.5 Torr), in AH (73.8 ± 0.2 Torr), and in CH (75.7 ± 0.1 Torr). Peripheral fatigue was expressed as pre- to postexercise percent reduction in electrically evoked potentiated quadriceps twitch force (ΔQtw,pot). Central fatigue was expressed as the exercise-induced percent decrease in voluntary muscle activation (ΔVA). Resting CaO2 at SL and CH was similar, but CaO2 in AH was lower compared with SL and CH (17.3 ± 0.5, 19.3 ± 0.7, 20.3 ± 1.3 ml O2/dl, respectively). Winsp during exercise increased with acclimatization (SL: 387 ± 36, AH: 503 ± 53, CH: 608 ± 67 cmH2O·s−1·min−1; P < 0.01). Exercise at SL did not induce central or peripheral fatigue. ΔQtw,pot was significant but similar in AH and CH (21 ± 2% and 19 ± 3%; P = 0.24). ΔVA was significant in both hypoxic conditions but smaller in CH vs. AH (4 ± 1% vs. 8 ± 2%; P < 0.05). In conclusion, acclimatization to severe altitude does not attenuate the substantial impact of hypoxia on the development of peripheral fatigue. In contrast, acclimatization attenuates, but does not eliminate, the exacerbation of central fatigue associated with exercise in severe AH.

Linear relationship between VO2max and VO2max decrement during exposure to acute hypoxia

1988 ◽  
Vol 64 (4) ◽  
pp. 1486-1492 ◽  
Author(s):  
J. Lawler ◽  
S. K. Powers ◽  
D. Thompson
Keyword(s):  
Maximal Exercise ◽  
Acute Hypoxia ◽  
Barometric Pressure ◽  
Endurance Athletes ◽  
Oxyhemoglobin Saturation ◽  
Hypoxia Exposure ◽  
Hypoxic Conditions ◽  
Significant Linear Correlation ◽  
Exercise Induced ◽  
Single Blind

The purpose of these experiments is to test the hypothesis that exercise-induced hypoxemia at sea level in highly trained athletes might be exacerbated during acute hypoxia and therefore result in correspondingly larger decrements in maximal O2 uptake (VO2max) compared with less trained individuals. Thirteen healthy male volunteers were divided into two groups according to their level of fitness: 1) trained endurance athletes (T) (n = 7), with a VO2max range of 56-75 ml.kg-1.min-1 and 2) untrained individuals (UT) (n = 6), with a VO2max range of 33-49 ml.kg-1.min-1. Subjects performed two incremental cycle ergometry tests to determine VO2max under hypoxic conditions [14% O2-86% N2, barometric pressure (PB) = 760 Torr] and normoxic conditions (21% O2-79% N2, PB = 760 Torr). Tests were single blind, randomly administered, and separated by at least 72 h. Mean percent oxyhemoglobin saturation (%SaO2) during maximal exercise under hypoxic conditions was significantly (P less than 0.05) lower in the T group (77%) compared with the UT group (86%). Furthermore, the T group exhibited larger decrements (P less than 0.05) in VO2max (normoxic-hypoxic) compared with the UT group. Finally, a significant linear correlation (r = 0.94) existed between normoxic VO2max (ml.kg-1.min-1) and delta VO2max (normoxic-hypoxic). These data suggest that highly T endurance athletes suffer more severe gas exchange impairments during acute exposure to hypoxia than UT individuals, and this may explain a portion of the observed variance in delta VO2max among individuals during acute altitude or hypoxia exposure.

scholarly journals Increased Brain Interstitial Fluid Adenosine Concentration during Hypoxia in Newborn Piglet

1987 ◽  
Vol 7 (2) ◽  
pp. 178-183 ◽  
Author(s):  
T. S. Park ◽  
David G. L. Van Wylen ◽  
Rafael Rubio ◽  
Robert M. Berne
Keyword(s):  
Frontal Cortex ◽  
Interstitial Fluid ◽  
Acute Hypoxia ◽  
Newborn Piglet ◽  
Cisterna Magna ◽  
Hypoxic Conditions ◽  
Adenosine Concentration ◽  
Brain Dialysis ◽  
The Brain ◽  
Dialysis Technique

The effects of arterial hypoxia on interstitial fluid adenosine concentrations were studied in the frontal cortex and thalamus by the brain dialysis technique and in CSF from the cisterna magna of the newborn piglet. Acute hypoxia (PaO2 = 20 ± 1 mm Hg) increased the interstitial fluid adenosine concentrations significantly from 0.68 ± 0.29 (SEM) to 1.60 ± 0.35 μ M in the frontal cortex and from 1.03 ± 0.32 to 2.60 ± 0.86 μ M in the thalamus (n = 8). Interstitial fluid inosine and hypoxanthine also increased significantly during hypoxia. In separate groups of piglets, the adenosine concentration in the cisterna magna CSF under normoxic conditions was 0.04 ± 0.01 μ M (n = 5), which increased significantly to 0.17 ± 0.04 μ M (n = 6) with hypoxia (PaO2 = 4.7 ± 1.2 mm Hg). Cisterna magna CSF inosine levels did not change significantly during the severe hypoxia. Adenosine concentrations found in the interstitial space and CSF of newborn piglets under normoxic and hypoxic conditions are within the vasodilator range. These results thus suggest that in the neonatal brain adenosine may play a role in regulating blood flow during hypoxia.

scholarly journals Effects of Padel Competition on Brain Health-Related Myokines

2021 ◽  
Vol 18 (11) ◽  
pp. 6042
Author(s):  
Francisco Pradas ◽  
María Pía Cádiz ◽  
María Teresa Nestares ◽  
Inmaculada C. Martínez-Díaz ◽  
Luis Carrasco
Keyword(s):  
Brain Health ◽  
Potential Health ◽  
Positive Effects ◽  
Brain Functions ◽  
Before And After ◽  
Health Related ◽  
Playing Time ◽  
Exercise Induced ◽  
The Brain

Padel is becoming one of the most widespread racket sports that may have potential health benefits. Considering that several myokines mediate the cross-talk between skeletal muscles and the brain, exerting positive effects on brain health status, this study was designed to evaluate the responses of brain-derived neurotrophic factor (BDNF), leukemia inhibitory factor (LIF), and irisin (IR) to padel competition in trained players and to determine whether these responses were sex-dependent. Twenty-four trained padel players (14 women and 10 men with a mean age of 27.8 ± 6.3 years) participated voluntarily in this study. Circulating levels of BDNF, LIF, and IR were assessed before and after simulated padel competition (real playing time, 27.8 ± 8.49 min; relative intensity, 75.2 ± 7.9% maximum heart rate). Except for BDNF responses observed in female players (increasing from 1531.12 ± 269.09 to 1768.56 ± 410.75 ng/mL), no significant changes in LIF and IR concentrations were reported after padel competition. In addition, no sex-related differences were found. Moreover, significant associations between IR and BDNF were established at both pre- and post-competition. Our results suggest that while competitive padel practice stimulates BDNF response in female players, padel competition failed to boost the release of LIF and IR. Future studies are needed to further explore the role of these exercise-induced myokines in the regulation of brain functions and to identify the field sports that can contribute to myokine-mediated muscle–brain crosstalk.

Effect of acute hypoxia on the hormonal response to exercise

1977 ◽  
Vol 42 (4) ◽  
pp. 587-592 ◽  
Author(s):  
J. R. Sutton
Keyword(s):  
Serum Insulin ◽  
Acute Hypoxia ◽  
Venous Blood ◽  
Cycle Ergometer ◽  
Serum Growth Hormone ◽  
Hormonal Responses ◽  
Hypoxic Conditions ◽  
Fat Mobilization ◽  
Response To Exercise ◽  
Hypoxic Exercise

The hormonal responses to submaximal exercise under normoxic and hypoxic conditions were studied in eight fit males, aged 22--28 yr, with mean maximal oxygen uptake of 4.4 +/- 0.7 l/min. Studies were performed in a hypobaric chamber, decompressed to a simulated altitude of 4,550 m (PIO2 = 83 Torr). The subjects exercised for 20 min at 750 kpm/min on a cycle ergometer. Venous blood samples were obtained at rest, during exercise and for 60 min after exercise. Plasma glucose, free fatty acids, lactate, cortisol, and serum growth hormone concentrations all increased more during hypoxic exercise than under normoxic conditions. Serum insulin concentration showed a small decrease under normoxic conditions, but decreased by 50% during hypoxic exercise, and was followed by marked rebound when exercise stopped. These changes suggest that energy substrate-hormone interrelationships are altered by hypoxic exercise, resulting in increased fat mobilization and increased gluconeogenesis.

scholarly journals Lactate as Potential Mediators for Exercise-Induced Positive Effects on Neuroplasticity and Cerebrovascular Plasticity

2021 ◽  
Vol 12 ◽  
Author(s):  
Zhihai Huang ◽  
Yulan Zhang ◽  
Ruixue Zhou ◽  
Luodan Yang ◽  
Hongying Pan
Keyword(s):  
Healthy Lifestyle ◽  
Protective Mechanism ◽  
Signal Molecule ◽  
Positive Role ◽  
Beneficial Effects ◽  
Positive Effects ◽  
Cerebrovascular Function ◽  
Cognitive Benefits ◽  
Exercise Induced ◽  
The Brain

The accumulated evidence from animal and human studies supports that exercise is beneficial to physical health. Exercise can upregulate various neurotrophic factors, activate neuroplasticity, and play a positive role in improving and enhancing cerebrovascular function. Due to its economy, convenience, and ability to prevent or ameliorate various aging-related diseases, exercise, a healthy lifestyle, is increasingly popularized by people. However, the mechanism by which exercise performs this function and how it is transmitted from muscles to the brain remains incompletely understood. Here, we review the beneficial effects of exercise with different intensities on the brain with a focus on the positive effects of lactate on neuroplasticity and cerebrovascular plasticity. Based on these recent studies, we propose that lactate, a waste previously misunderstood as a by-product of glycolysis in the past, may be a key signal molecule that regulates the beneficial adaptation of the brain caused by exercise. Importantly, we speculate that a central protective mechanism may underlie the cognitive benefits induced by exercise.

Undesirable Effects of Goal Setting on Perceived Fairness, Commitment, and Unethical Behavior

2018 ◽  
Vol 62 (2) ◽  
pp. 97-107 ◽  
Author(s):  
Nina Keith
Keyword(s):  
Goal Setting ◽  
Unethical Behavior ◽  
The United States ◽  
Goal Commitment ◽  
Management Technique ◽  
Long Term Effects ◽  
Perceived Fairness ◽  
Negative Effects ◽  
Positive Effects ◽  
And Performance

Abstract. The positive effects of goal setting on motivation and performance are among the most established findings of industrial–organizational psychology. Accordingly, goal setting is a common management technique. Lately, however, potential negative effects of goal-setting, for example, on unethical behavior, are increasingly being discussed. This research replicates and extends a laboratory experiment conducted in the United States. In one of three goal conditions (do-your-best goals, consistently high goals, increasingly high goals), 101 participants worked on a search task in five rounds. Half of them (transparency yes/no) were informed at the outset about goal development. We did not find the expected effects on unethical behavior but medium-to-large effects on subjective variables: Perceived fairness of goals and goal commitment were least favorable in the increasing-goal condition, particularly in later goal rounds. Results indicate that when designing goal-setting interventions, organizations may consider potential undesirable long-term effects.

Mobilizing for Some

2016 ◽  
Vol 28 (3) ◽  
pp. 123-135 ◽  
Author(s):  
Raffael Heiss ◽  
Jörg Matthes
Keyword(s):  
High School ◽  
Social Media ◽  
High School Students ◽  
Experimental Design ◽  
Collective Efficacy ◽  
Political Efficacy ◽  
Negative Effects ◽  
School Students ◽  
Positive Effects ◽  
Specific Factors

Abstract. This study investigated the effects of politicians’ nonparticipatory and participatory Facebook posts on young people’s political efficacy – a key determinant of political participation. We employed an experimental design, using a sample of N = 125 high school students (15–20 years). Participants either saw a Facebook profile with no posts (control condition), nonparticipatory posts, or participatory posts. While nonparticipatory posts did not affect participants’ political efficacy, participatory posts exerted distinct effects. For those high in trait evaluations of the politician presented in the stimulus material or low in political cynicism, we found significant positive effects on external and collective efficacy. By contrast, for those low in trait evaluations or high in cynicism, we found significant negative effects on external and collective efficacy. We did not find any effects on internal efficacy. The importance of content-specific factors and individual predispositions in assessing the influence of social media use on participation is discussed.

On the diversity of the effects of the state support for agriculture

2019 ◽  
pp. 59-73 ◽  
Author(s):  
Nikolai M. Svetlov ◽  
Renata G. Yanbykh ◽  
Dariya A. Loginova
Keyword(s):  
Agricultural Production ◽  
The State ◽  
Russian Regions ◽  
Negative Effects ◽  
State Support ◽  
Soft Budget Constraints ◽  
Institutional Conditions ◽  
Positive Effects ◽  
Production Factors ◽  
Corporate Farms

In this paper, we assess the effects of agricultural state support of corporate farms on their revenues from agricultural production sales in 14 Russian regions that differ in technology, environment and institutional conditions. In addition to the direct effect of the state support, the indirect effects via labor and capital are revealed. For this purpose, we identify production functions and statistical models of production factors for each of these regions separately. We find out diverse effects of the state support on revenues among the regions. Positive effects prevail. Negative effects are mainly caused by labor reductions that follow subsidy inflows. Another cause of negative effects is the soft budget constraints phenomenon.

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