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1.
Sci Rep ; 14(1): 897, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195912

RESUMO

The aerosol and precipitable water vapor (PW) distribution over the tropical Andes region is characterized using Aerosol Robotic Network (AERONET) observations at stations in Medellin (Colombia), Quito (Ecuador), Huancayo (Peru), and La Paz (Bolivia). AERONET aerosol optical depth (AOD) is interpreted using PM2.5 data when available. Columnar water vapor derived from ozone soundings at Quito is used to compare against AERONET PW. MERRA-2 data are used to complement analyses. Urban pollution and biomass burning smoke (BBS) dominate the regional aerosol composition. AOD and PM2.5 yearly cycles for coincident measurements correlate linearly at Medellin and Quito. The Andes cordillera's orientation and elevation funnel or block BBS transport into valleys or highlands during the two fire seasons that systematically impact South America. The February-March season north of Colombia and the Colombian-Venezuelan border directly impacts Medellin. Possibly, the March aerosol signal over Quito has a long-range transport component. At Huancayo and La Paz, AOD increases in September due to the influence of BBS in the Amazon. AERONET PW and sounding data correlate linearly but a dry bias with respect to soundings was identified in AERONET. PW and rainfall progressively decrease from north to south due to increasing altitude. This regional diagnosis is an underlying basis to evaluate future changes in aerosol and PW given prevailing conditions of rapidly changing atmospheric composition.

2.
J Neurosurg Case Lessons ; 6(20)2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37956423

RESUMO

BACKGROUND: Posttraumatic intradural hematomas of the cervical spine are rare findings that may yield significant neurological deficits if they compress the spinal cord. These compressive hematomas require prompt surgical evacuation. In certain instances, intradural hematomas may form from avulsion of cervical nerve roots. OBSERVATIONS: The authors present the case of a 29-year-old male who presented with right upper-extremity weakness in the setting of polytrauma after a motor vehicle accident. He had no cervical fractures but subsequently developed right lower-extremity weakness. Magnetic resonance imaging (MRI) demonstrated a compressive hematoma of the cervical spine that was initially read as an epidural hematoma. However, intraoperatively, it was found to be a subdural hematoma, eccentric to the right, stemming from an avulsion of the right C6 nerve root. LESSONS: Posttraumatic cervical subdural hematomas require rapid surgical evacuation if neurological deficits are present. The source of the hematoma may be an avulsed nerve root, and the associated deficits may be unilateral if the hematoma is eccentric to one side. Surgeons should be prepared for the possibility of an intradural hematoma even in instances in which MRI appears consistent with an epidural hematoma.

3.
Biochem Biophys Rep ; 35: 101504, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37601446

RESUMO

Background: The incorporation of exogenous fatty acids into the cell membrane yields structural modifications that directly influence membrane phospholipid composition and indirectly contribute to virulence. FadL and FadD are responsible for importing and activating exogenous fatty acids, while acyltransferases (PlsB, PlsC, PlsX, PlsY) incorporate fatty acids into the cell membrane. Many Gammaproteobacteria species possess multiple homologs of these proteins involved in exogenous fatty acid metabolism, suggesting the evolutionary acquisition and maintenance of this transport pathway. Methods: This study developed phylogenetic trees based on amino acid and nucleotide sequences of homologs of FadL, FadD, PlsB, PlsC, PlsX, and PlsY via Mr. Bayes and RAxML algorithms. We also explored the operon arrangement of genes encoding for FadL. Additionally, FadL homologs were modeled via SWISS-MODEL, validated and refined by SAVES, Galaxy Refine, and GROMACS, and docked with fatty acids via AutoDock Vina. Resulting affinities were analyzed by 2-way ANOVA test and Tukey's post-hoc test. Results: Our phylogenetic trees revealed grouping based on operon structure, original homolog blasted from, and order of the homolog, suggesting a more ancestral origin of the multiple homolog phenomena. Our molecular docking simulations indicated a similar binding pattern for the fatty acids between the different FadL homologs. General significance: Our study is the first to illustrate the phylogeny of these proteins and to investigate the binding of various FadL homologs across orders with fatty acids. This study helps unravel the mystery surrounding these proteins and presents topics for future research.

4.
J Fish Dis ; 46(1): 31-45, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36088584

RESUMO

Aeromonas salmonicida is a Gram-negative bacterium that can infect a wide host range of fish populations, including salmonids and non-salmonids as well as freshwater and marine life. Some strains of A. salmonicida cause the disease furunculosis, which can cause lethargy, intestinal inflammation, ulcers, haemorrhaging and death. The infection is spread through fish-to-fish contact, and the presence of infection can have devastating effects on cultivated fish populations. The purpose of this study was to explore the ability of non-A-layer and A-layer A. salmonicida strains to incorporate polyunsaturated fatty acids (PUFAs) into their lipid profile and test the phenotypic effects thereof. Lipids were extracted from PUFA-exposed cultures and analysed for lipid modification by thin-layer chromatography and ultraperformance liquid chromatography-mass spectrometry, showing A. salmonicida, regardless of A-layer, capable of incorporating all seven of the PUFAs studied. Phenotypic effects were determined through the use of assays that tested for biofilm formation, membrane permeability and cyclic peptide susceptibility. Temperature-dependent effects on biofilm formation were observed, and PUFA exposure showed significant (p < .001) increases in membrane permeability as tested by the uptake of the hydrophobic compounds crystal violet and ethidium bromide. Additionally, some PUFAs elicited modest protection and vulnerability against the membrane-targeting cyclic peptides polymyxin B (PMB) and colistin. The diverse, strain-specific responses to exogenous PUFAs may allude to evolved adaptive strategies that enhance survival, persistence and virulence of non-pathogenic and pathogenic members of bacteria that oscillate between environmental and fish host niches.


Assuntos
Aeromonas salmonicida , Doenças dos Peixes , Animais , Peptídeos Antimicrobianos , Fosfolipídeos , Ácidos Graxos Insaturados
5.
Biomolecules ; 12(9)2022 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-36139109

RESUMO

Fatty acids (FA) play an important role in biological functions, such as membrane homeostasis, metabolism, and as signaling molecules. FadL is the only known protein that uptakes long-chain fatty acids in Gram-negative bacteria, and this uptake has traditionally been thought to be limited to fatty acids up to 18 carbon atoms in length. Recently however, it was found Vibrio cholerae has the ability to uptake fatty acids greater than 18 carbon atoms and this uptake corresponds to bacterial survivability. Using E. coli's FadL as a template, V. cholerae FadL homologs vc1042, vc1043, and vca0862 have been computationally folded, simulated on an atomistic level using Molecular Dynamics, and docked in silico to analyze the FadL transport channels. For the vc1042 and vc1043 homologs, these transport channels have more structural accommodations for the many rigid unsaturated bonds of long-chain polyunsaturated fatty acids, while the vca0862 homolog was found to lack transport channels within the signature beta barrel of FadL proteins.


Assuntos
Escherichia coli , Vibrio cholerae , Proteínas de Bactérias/metabolismo , Transporte Biológico , Carbono/metabolismo , Escherichia coli/metabolismo , Ácidos Graxos/metabolismo , Ácidos Graxos Insaturados/metabolismo , Vibrio cholerae/metabolismo
6.
Front Psychol ; 13: 841932, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35936292

RESUMO

Background: Compassion focused therapy (CFT) is an evolutionary informed, biopsychosocial approach to mental health problems and therapy. It suggests that evolved motives (e.g., for caring, cooperating, competing) are major sources for the organisation of psychophysiological processes which underpin mental health problems. Hence, evolved motives can be targets for psychotherapy. People with certain types of depression are psychophysiologically orientated towards social competition and concerned with social status and social rank. These can give rise to down rank-focused forms of social comparison, sense of inferiority, worthlessness, lowered confidence, submissive behaviour, shame proneness and self-criticism. People with bipolar disorders also experience elevated aspects of competitiveness and up rank status evaluation. These shift processing to a sense of superiority, elevated confidence, energised behaviour, positive affect and social dominance. This is the first study to explore the feasibility of a 12 module CFT group, tailored to helping people with a diagnosis of bipolar disorder understand the impact of evolved competitive, status-regulating motivation on their mental states and the value of cultivating caring and compassion motives and their psychophysiological regulators. Methods: Six participants with a history of bipolar disorder took part in a CFT group consisting of 12 modules (over 25 sessions) as co-collaborators to explore their personal experiences of CFT and potential processes of change. Assessment of change was measured via self-report, heart rate variability (HRV) and focus groups over three time points. Results: Although changes in self-report scales between participants and across time were uneven, four of the six participants consistently showed improvements across the majority of self-report measures. Heart rate variability measures revealed significant improvement over the course of the therapy. Qualitative data from three focus groups revealed participants found CFT gave them helpful insight into: how evolution has given rise to a number of difficult problems for emotion regulation (called tricky brain) which is not one's fault; an evolutionary understanding of the nature of bipolar disorders; development of a compassionate mind and practices of compassion focused visualisations, styles of thinking and behaviours; addressing issues of self-criticism; and building a sense of a compassionate identity as a means of coping with life difficulties. These impacted their emotional regulation and social relationships. Conclusion: Although small, the study provides evidence of feasibility, acceptability and engagement with CFT. Focus group analysis revealed that participants were able to switch from competitive focused to compassion focused processing with consequent improvements in mental states and social behaviour. Participants indicated a journey over time from 'intellectually' understanding the process of building a compassionate mind to experiencing a more embodied sense of compassion that had significant impacts on their orientation to (and working with) the psychophysiological processes of bipolar disorder.

7.
J Geophys Res Atmos ; 127(7): e2021JD034905, 2022 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-35865790

RESUMO

We introduce and evaluate an approach for the simultaneous retrieval of aerosol and surface properties from Airborne Visible/Infrared Imaging Spectrometer Classic (AVIRIS-C) data collected during wildfires. The joint National Aeronautics and Space Administration (NASA) National Oceanic and Atmospheric Administration Fire Influence on Regional to Global Environments and Air Quality field campaign took place in August 2019, and involved two aircraft and coordinated ground-based observations. The AVIRIS-C instrument acquired data from onboard NASA's high altitude ER-2 research aircraft, coincident in space and time with aerosol observations obtained from the Aerosol Robotic Network (AERONET) DRAGON mobile platform in the smoke plume downwind of the Williams Flats Fire in northern Washington in August 2019. Observations in this smoke plume were used to assess the capacity of optimal-estimation based retrievals to simultaneously estimate aerosol optical depth (AOD) and surface reflectance from Visible Shortwave Infrared (VSWIR) imaging spectroscopy. Radiative transfer modeling of the sensitivities in spectral information collected over smoke reveal the potential capacity of high spectral resolution retrievals to distinguish between sulfate and smoke aerosol models, as well as sensitivity to the aerosol size distribution. Comparison with ground-based AERONET observations demonstrates that AVIRIS-C retrievals of AOD compare favorably with direct sun AOD measurements. Our analyses suggest that spectral information collected from the full VSWIR spectral interval, not just the shortest wavelengths, enables accurate retrievals. We use this approach to continuously map both aerosols and surface reflectance at high spatial resolution across heterogeneous terrain, even under relatively high AOD conditions associated with wildfire smoke.

8.
J Strength Cond Res ; 36(8): 2277-2282, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32149883

RESUMO

ABSTRACT: Torr, O, Randall, T, Knowles, R, Giles, D, and Atkins, S. The reliability and validity of a method for the assessment of sport rock climbers' isometric finger strength. J Strength Cond Res 36(8): 2277-2282, 2022-Isometric strength of the finger flexors is considered to be one of the main physical determinants of sport rock climbing performance. We set out to determine the test-retest reliability and criterion validity of a low resource maximal isometric finger strength (MIFS) testing protocol that uses a pulley system to add or remove weight to/from a climber's body. To determine test-retest reliability, 15 subjects' MIFS was assessed on 2 occasions, separated by a minimum of 48 hours. Body mass and maximum load were recorded on both occasions. Intra-class correlation coefficients (ICCs) between visits for all variables were very good (ICC > 0.91), with small bias and effect sizes-particularly when expressed as a percentage of body mass (ICC = 0.98, 95% confidence interval 0.93-0.99). To determine the criterion validity of MIFS and climbing ability, data of 229 intermediate to higher elite climbers were compared. Pearson's product moment correlations demonstrated good agreement, again particularly between total load when expressed as a percentage of body mass and climbing performance ( r = 0.421-0.503). The results illustrate the sensitivity of a simple test for the determination of MIFS in intermediate to height elite climbers from an ecologically valid, climbing specific test that only requires equipment found at most climbing walls. This low resource test protocol for the assessment of isometric finger strength has wide-reaching utility, for instance when assessing strength before and after a training intervention or when prescribing load intensities for exercises aimed at improving maximal finger strength.


Assuntos
Montanhismo , Esportes , Dedos , Humanos , Reprodutibilidade dos Testes , Extremidade Superior
10.
Microbiologyopen ; 10(5): e1237, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34713610

RESUMO

Vibrio alginolyticus and Vibrio (Aliivibrio) fischeri are Gram-negative bacteria found globally in marine environments. During the past decade, studies have shown that certain Gram-negative bacteria, including Vibrio species (cholerae, parahaemolyticus, and vulnificus) are capable of using exogenous polyunsaturated fatty acids (PUFAs) to modify the phospholipids of their membrane. Moreover, exposure to exogenous PUFAs has been shown to affect certain phenotypes that are important factors of virulence. The purpose of this study was to investigate whether V. alginolyticus and V. fischeri are capable of responding to exogenous PUFAs by remodeling their membrane phospholipids and/or altering behaviors associated with virulence. Thin-layer chromatography (TLC) analyses and ultra-performance liquid chromatography-electrospray ionization mass spectrometry (UPLC/ESI-MS) confirmed incorporation of all PUFAs into membrane phosphatidylglycerol and phosphatidylethanolamine. Several growth phenotypes were identified when individual fatty acids were supplied in minimal media and as sole carbon sources. Interestingly, several PUFAs acids inhibited growth of V. fischeri. Significant alterations to membrane permeability were observed depending on fatty acid supplemented. Strikingly, arachidonic acid (20:4) reduced membrane permeability by approximately 35% in both V. alginolyticus and V. fischeri. Biofilm assays indicated that fatty acid influence was dependent on media composition and temperature. All fatty acids caused decreased swimming motility in V. alginolyticus, while only linoleic acid (18:2) significantly increased swimming motility in V. fischeri. In summary, exogenous fatty acids cause a variety of changes in V. alginolyticus and V. fischeri, thus adding these bacteria to a growing list of Gram-negatives that exhibit versatility in fatty acid utilization and highlighting the potential for environmental PUFAs to influence phenotypes associated with planktonic, beneficial, and pathogenic associations.


Assuntos
Aliivibrio fischeri/fisiologia , Permeabilidade da Membrana Celular , Membrana Celular/metabolismo , Ácidos Graxos Insaturados/metabolismo , Fosfatidiletanolaminas/metabolismo , Fosfatidilgliceróis/metabolismo , Vibrio alginolyticus/fisiologia , Organismos Aquáticos/fisiologia , Biofilmes , Fenótipo , Vibrioses/microbiologia , Virulência/efeitos dos fármacos
11.
J Funct Morphol Kinesiol ; 6(2)2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33925974

RESUMO

Past attempts to define an anaerobic threshold (AnT) have relied upon gas exchange kinetics, lactate testing and field-based evaluations. DFA a1, an index of heart rate (HR) variability (HRV) fractal correlation properties, has been shown to decrease with exercise intensity. The intent of this study is to investigate whether the AnT derived from gas exchange is associated with the transition from a correlated to uncorrelated random HRV pattern signified by a DFA a1 value of 0.5. HRV and gas exchange data were obtained from 15 participants during an incremental treadmill run. Comparison of the HR reached at the second ventilatory threshold (VT2) was made to the HR reached at a DFA a1 value of 0.5 (HRVT2). Based on Bland-Altman analysis and linear regression, there was strong agreement between VT2 and HRVT2 measured by HR (r = 0.78, p < 0.001). Mean VT2 was reached at a HR of 174 (±12) bpm compared to mean HRVT2 at a HR of 171 (±16) bpm. In summary, the HR associated with a DFA a1 value of 0.5 on an incremental treadmill ramp was closely related to that of the HR at the VT2 derived from gas exchange analysis. A distinct numerical value of DFA a1 representing an uncorrelated, random interbeat pattern appears to be associated with the VT2 and shows potential as a noninvasive marker for training intensity distribution and performance status.

12.
Int J Sports Physiol Perform ; 16(9): 1242-1252, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-33652414

RESUMO

PURPOSE: To examine the validity and reliability of a battery of 10 measures designed to assess the key physiological parameters for successful rock climbing performance. METHODS: In phase 1 of the research, an expert panel, using the Delphi method, established a 10-item test battery based on the key determinants of climbing performance. In phase 2, the tests were assessed for validity and reliability to examine their suitability as sport-specific measures of rock climbing performance. A total of 132 rock climbers, from 7 countries, volunteered to take part in the study. Each climber visited their nearest laboratory on 3 separate occasions in order to enable the required tests and retests to be completed. A minimum of 7 days was allowed between visits. RESULTS: The 10 tests established for phase 2 were designed as sport-specific measures of flexibility, strength, power, and endurance. Results indicated that, while reliable, the flexibility and strength tests were only partially successful in differentiating across climber abilities. The power and endurance tests, however, performed well with regard to validity and reliability, with the finger hang and powerslap tests being most strongly correlated with performance ability (P < .0005 to P < .002). CONCLUSION: The authors' data suggest that climbing may require a threshold level of flexibility and strength for successful performance, beyond which further improvements may not be required. In contrast, the finger hang and powerslap tests were not only reliable measures but also differentiated between climber abilities from lower grade to elite levels.


Assuntos
Montanhismo , Esportes , Força da Mão/fisiologia , Humanos , Montanhismo/fisiologia , Resistência Física/fisiologia , Reprodutibilidade dos Testes , Esportes/fisiologia
13.
Int J Sports Physiol Perform ; 16(7): 942-949, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33647876

RESUMO

PURPOSE: The fatigue resistance of the finger flexors is known to be a key determinant of climbing performance. This study set out to establish the association between the single all-out assessment of finger flexor critical force (ff-CF) and the impulse above CF (W') on climbing performance (self-reported sport and boulder climbing ability). METHODS: A total of 129 subjects completed an assessment of dominant arm ff-CF, comprised of a series of rhythmic isometric maximum voluntary contractions (CF defined as mean end-test force [in kilograms]; W' impulse above CF [in kilogram second]). RESULTS: The ff-CF protocol resulted in the same force decay to a plateau seen in previous isometric critical torque and critical force tests. Linear regression analysis, adjusting for sex, revealed that CF percentage of body mass explained 61% of sport and 26% of bouldering performance and W' per kilogram body mass explained 7% sport and 34% bouldering performance. A combined model of CF as a percentage of body mass and W' per kilogram body mass, after adjustment for sex differences, was able to explain 66% of sport climbing and 44% of bouldering performance. CONCLUSIONS: The results illustrate the relevance of the CF threshold in describing the fatigue resistance of the finger flexors of rock climbers. Given ff-CF ability to describe a considerable proportion of variance in sport climbing and bouldering ability, the authors expect it to become a common test used by coaches for understanding exercise tolerance and for determining optimal training prescription.


Assuntos
Montanhismo , Esportes , Tolerância ao Exercício , Feminino , Dedos , Humanos , Contração Isométrica , Masculino
14.
Sensors (Basel) ; 21(3)2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33530473

RESUMO

Recent study points to the value of a non-linear heart rate variability (HRV) biomarker using detrended fluctuation analysis (DFA a1) for aerobic threshold determination (HRVT). Significance of recording artefact, correction methods and device bias on DFA a1 during exercise and HRVT is unclear. Gas exchange and HRV data were obtained from 17 participants during an incremental treadmill run using both ECG and Polar H7 as recording devices. First, artefacts were randomly placed in the ECG time series to equal 1, 3 and 6% missed beats with correction by Kubios software's automatic and medium threshold method. Based on linear regression, Bland Altman analysis and Wilcoxon paired testing, there was bias present with increasing artefact quantity. Regardless of artefact correction method, 1 to 3% missed beat artefact introduced small but discernible bias in raw DFA a1 measurements. At 6% artefact using medium correction, proportional bias was found (maximum 19%). Despite this bias, the mean HRVT determination was within 1 bpm across all artefact levels and correction modalities. Second, the HRVT ascertained from synchronous ECG vs. Polar H7 recordings did show an average bias of minus 4 bpm. Polar H7 results suggest that device related bias is possible but in the reverse direction as artefact related bias.


Assuntos
Artefatos , Eletrocardiografia , Biomarcadores , Teste de Esforço , Frequência Cardíaca , Humanos
15.
Eur J Appl Physiol ; 121(5): 1337-1348, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33591426

RESUMO

PURPOSE: Sport climbing requires high-intensity finger flexor contractions, along with a substantial whole-body systemic oxygen uptake ([Formula: see text]O2) contribution. Although fatigue is often localised to the finger flexors, the role of systemic ̇[Formula: see text]O2 and local aerobic mechanisms in climbing performance remains unclear. As such, the primary purpose of this study was to determine systemic and local muscle oxygen responses during both isolated finger flexion and incremental exhaustive whole-body climbing tests. The secondary aim was to determine the relationship of isolated and whole-body climbing endurance tests to climbing ability. METHODS: Twenty-two male sport climbers completed a series of isometric sustained and intermittent forearm flexor contractions, and an exhaustive climbing test with progressive steepening of the wall angle on a motorised climbing ergometer. Systemic [Formula: see text]O2 and flexor digitorum profundus oxygen saturation (StO2) were recorded using portable metabolic analyser and near-infra red spectroscopy, respectively. RESULTS: Muscle oxygenation breakpoint (MOB) was identifiable during an incremental exhaustive climbing test with progressive increases in angle (82 ± 8% and 88 ± 8% [Formula: see text]O2 and heart rate climbing peak). The peak angle from whole-body treadwall test and impulse from isolated hangboard endurance tests were interrelated (R2 = 0.58-0.64). Peak climbing angle together with mean [Formula: see text]O2 and StO2 from submaximal climbing explained 83% of variance in self-reported climbing ability. CONCLUSIONS: Both systemic and muscle oxygen kinetics determine climbing-specific endurance. Exhaustive climbing and isolated finger flexion endurance tests are interrelated and suitable to assess climbing-specific endurance. An exhaustive climbing test with progressive wall angle allows determination of the MOB.


Assuntos
Dedos/fisiologia , Força da Mão/fisiologia , Montanhismo/fisiologia , Músculo Esquelético/fisiologia , Resistência Física/fisiologia , Adulto , Humanos , Masculino , Contração Muscular/fisiologia , Fadiga Muscular/fisiologia , Consumo de Oxigênio/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho
16.
Sci Rep ; 11(1): 2639, 2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33514833

RESUMO

The purpose of the study was to compare the psychophysiological response of climbers of a range of abilities (lower grade to advanced) when ascending identical climbing routes on a climbing wall and a rotating treadwall. Twenty-two female climbers (31.2 ± 9.4 years; 60.5 ± 6.5 kg; 168.6 ± 5.7 cm) completed two identical 18 m climbing trials (graded 4 on the French Sport scale) separated by 1 week, one on the treadwall (climbing low to the ground) and the other on the indoor wall (climbing in height). Indirect calorimetry, venous blood samples and video-analysis were used to assess energy cost, hormonal response and time-load characteristics. Energy costs were higher during indoor wall climbing comparing to those on the treadwall by 16% (P < 0.001, [Formula: see text] = 0.48). No interaction of climbing ability and climbing condition were found. However, there was an interaction for climbing ability and post-climbing catecholamine concentration (P < 0.01, [Formula: see text] = 0.28). Advanced climbers' catecholamine response increased by 238% and 166% with respect to pre-climb values on the treadwall and indoor wall, respectively; while lower grade climbers pre-climb concentrations were elevated by 281% and 376% on the treadwall and indoor wall, respectively. The video analysis showed no differences in any time-motion variables between treadwall and indoor wall climbing. The study demonstrated a greater metabolic response for indoor wall climbing, however, the exact mechanisms are not yet fully understood.


Assuntos
Desempenho Atlético/fisiologia , Montanhismo/fisiologia , Psicofisiologia/estatística & dados numéricos , Adulto , Feminino , Força da Mão/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Consumo de Oxigênio/fisiologia , Psicofisiologia/normas
17.
Front Physiol ; 12: 792376, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35069253

RESUMO

Purpose: Sport climbing is a technical, self-paced sport, and the workload is highly variable and mainly localized to the forearm flexors. It has not proved effective to control intensity using measures typical of other sports, such as gas exchange thresholds, heart rate, or blood lactate. Therefore, the purposes of the study were to (1) determine the possibility of applying the mathematical model of critical power to the estimation of a critical angle (CA) as a measure of maximal metabolic steady state in climbing and (2) to compare this intensity with the muscle oxygenation breakpoint (MOB) determined during an exhaustive climbing task. Materials and Methods: Twenty-seven sport climbers undertook three to five exhaustive ascents on a motorized treadwall at differing angles to estimate CA, and one exhaustive climbing test with a progressive increase in angle to determine MOB, assessed using near-infrared spectroscopy (NIRS). Results: Model fit for estimated CA was very high (R 2 = 0.99; SEE = 1.1°). The mean peak angle during incremental test was -17 ± 5°, and CA from exhaustive trials was found at -2.5 ± 3.8°. Nine climbers performing the ascent 2° under CA were able to sustain the task for 20 min with perceived exertion at 12.1 ± 1.9 (RPE). However, climbing 2° above CA led to task failure after 15.9 ± 3.0 min with RPE = 16.4 ± 1.9. When MOB was plotted against estimated CA, good agreement was stated (ICC = 0.80, SEM = 1.5°). Conclusion: Climbers, coaches, and researchers may use a predefined route with three to five different wall angles to estimate CA as an analog of critical power to determine a maximal metabolic steady state in climbing. Moreover, a climbing test with progressive increases in wall angle using MOB also appears to provide a valid estimate of CA.

18.
Eur J Sport Sci ; 21(9): 1290-1298, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33201779

RESUMO

Anthocyanin-rich New Zealand blackcurrant (NZBC) may improve forearm muscle oxygenation and enhance performance in high-level rock climbers. As such, using a double-blind, randomised, cross-over design study, twelve participants performed an oxidative capacity assessment, and two successive exhaustive exercise trials (submaximal forearm muscle contractions at 60% of their maximal volitional contraction). Each visit was conducted following 7-days intake of 600 mg·day-1 NZBC extract or placebo. Oxidative capacity was estimated by calculating the oxygen half time recovery using near infrared spectroscopy. Time to exhaustion (s), impulse (kg·s), and minimum tissue saturation index (min-TSI %) were assessed during both the exercise trials. Muscle oxidative capacity was greater with NZBC (mean difference [MD] = 5.3 s, 95% confidence intervals [95% CI] = 0.4-10.2 s; p = 0.036; Cohen's d = 0.94). During the exercise trials, there was an interaction for min-TSI % (time x condition, p = 0.046; ηp2 = 0.372), which indicated a greater level of oxygen extraction during trial two with NZBC extract (MD = 9%, 95% CI = 2-15%) compared to the placebo (MD = 2%, 95% CI = 1-7%). There was a decrease in time to exhaustion (p <0.001, ηp2 = 0.693) and impulse (p = 0.001, ηp2 = 0.672) in exercise trial two, with no effect of NZBC extract. In high-level rock climbers 7-days NZBC extract improves forearm muscle oxygenation with no effect on isolated forearm muscle performance.


Assuntos
Desempenho Atlético/fisiologia , Montanhismo/fisiologia , Músculo Esquelético/fisiologia , Extratos Vegetais/administração & dosagem , Ribes/química , Adulto , Estudos Cross-Over , Método Duplo-Cego , Antebraço/fisiologia , Humanos , Masculino , Consumo de Oxigênio , Espectroscopia de Luz Próxima ao Infravermelho , Adulto Jovem
19.
J Sports Sci ; 39(1): 48-56, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32808569

RESUMO

Despite climbing's popularity and an increasing number of female participants, there are limited anthropometric and performance data for this population. This study compares the characteristics of 55 experienced female climbers, divided into three categories (lower [ADV-L] and higher advanced [ADV-H] and elite [ELT]) based on self-reported ability. Data on climbing experience, body dimensions, body composition, flexibility, lower and upper-body power and finger strength were assessed. ELT climbers differed significantly from the ADV groups in age (Mean Difference [MD] = 8.8-9.8 yrs; despite smaller differences in years climbing MD = 1.6-2.4 yrs), greater climbing and hours training per week (MD = 3.0-3.7 h & MD = 0.9-1.6 h, respectively), and greater upper-body power (MD = 12.9-16.6 cm) and finger strength (MD = 51.6-65.4 N). Linear regression analysis showed finger strength and upper body power to be associated with ability, particularly when adjusting for descriptive and anthropometric variables (finger strength R2 = 53% and 45%; upper-body power R2 = 60% and 39% for boulder and sport, respectively). The findings support the importance of finger strength and upper-body power; changes in female anthropometric data over the last decade provide insight into the changing nature of the sport.


Assuntos
Atletas , Desempenho Atlético/fisiologia , Tamanho Corporal/fisiologia , Dedos/fisiologia , Força da Mão/fisiologia , Montanhismo/fisiologia , Adulto , Fatores Etários , Braço/anatomia & histologia , Atletas/classificação , Desempenho Atlético/classificação , Estatura , Índice de Massa Corporal , Feminino , Humanos , Perna (Membro)/anatomia & histologia , Modelos Lineares , Montanhismo/classificação , Montanhismo/tendências , Força Muscular/fisiologia , Autorrelato , Dobras Cutâneas , Fatores de Tempo
20.
PLoS One ; 15(10): e0240220, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33031480

RESUMO

Heart rate variability (HRV) measurements via ambulatory monitors have become common. We examined the validity of recording R-R intervals using the Polar V800™ compared to 12-lead electrocardiograms (ECG) among middle-aged (44.7±10.1years); overweight to obese (29.8±4.3 kg.m-2) adults (n = 25) with hypertension (132.3±12.2/ 84.3±10.2 mmHg). After resting for 5-min in the supine position, R-R intervals were simultaneously recorded using the Polar V800™ and the 12-lead ECG. Artifacts present in uncorrected (UN) R-R intervals were corrected with the Kubios HRV Premium (ver. 3.2.) automatic (AC) and threshold-based (TBC) correction, and manual correction (MC) methods. Intra-class correlation coefficients (ICC), Bland-Altman limits of agreement (LoA), and effect sizes (ES) were calculated. We detected 71 errors with the Polar V800™ for an error rate of 0.85%. The bias (LoAs), ES, and ICC between UN and ECG R-R intervals were 0.69ms (-215.80 to +214.42ms), 0.004, and 0.79, respectively. Correction of artifacts improved the agreeability between the Polar V800™ and ECG HRV measures. The biases (LoAs) between the AC, TBC, and MC and ECG R-R intervals were 3.79ms (-130.32 to +137.90ms), 1.16ms (-92.67 to +94.98ms), and 0.37ms (-41.20 to +41.94ms), respectively. The ESs of AC, TBC, and MC were 0.024, 0.008, and 0.002, and ICCs were 0.91, 0.95, and 1.00, respectively. R-R intervals measured using the Polar V800™ compared to 12-lead ECG were comparable in adults with hypertension, especially after the artifacts corrected by MC. However, TBC correction also yielded acceptable results.


Assuntos
Artefatos , Frequência Cardíaca , Hipertensão/fisiopatologia , Monitorização Fisiológica/métodos , Adulto , Envelhecimento/fisiologia , Índice de Massa Corporal , Eletrocardiografia , Feminino , Humanos , Hipertensão/tratamento farmacológico , Masculino , Pessoa de Meia-Idade
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