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2.
Nutrients ; 16(6)2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38542678

RESUMEN

This study aimed to characterize the composition of lipids in the red blood cells (RBCs) of adolescent swimmers and correlate this lipidome with the aerobic performance of the athletes. Five experimental assessments were performed by 37 adolescent swimmers. During the first session, the athletes went to the laboratory facility for venous blood sampling. The critical velocity protocol was conducted over the 4 subsequent days to measure aerobic performance (CV), comprising maximal efforts over distances of 100, 200, 400, and 800 m in a swimming pool. RBCs were obtained and extracted for analysis using the liquid chromatography-high resolution mass spectrometry untargeted approach. A total of 2146 ions were detected in the RBCs, of which 119 were identified. The enrichment pathway analysis indicated intermediary lipids in the glycerophospholipid, glycerolipid, sphingolipid, linoleic acid, and alpha-linolenic metabolisms, as well as pentose and glucuronate interconversions. A significant impact of the intermediary lipids was observed for the glycerophospholipid metabolism, including phosphatidylethanolamine (PE), phosphatidylcholine (PC), 1-acyl-sn-glycero-3-phosphocholine, sn-glycerol 3-phosphate, and phosphatidic acid. Inverse and significant associations were observed for PE 18:2/18:3 (r = -0.39; p = 0.015), PC 18:3/20:0 (r = -0.33; p = 0.041), and phosphatidic acid 18:0/0:0 (r = -0.47; p = 0.003) with aerobic performance. Swimmers who exhibited higher levels of aerobic performance also had the lowest abundance of PE, PC, and phosphatidic acid.


Asunto(s)
Glicerofosfolípidos , Fosfatidilcolinas , Adolescente , Humanos , Ácidos Fosfatidicos , Glicerilfosforilcolina , Eritrocitos
3.
Sports Health ; 16(1): 70-78, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-36872593

RESUMEN

CONTEXT: Melatonin is an ancient molecule with a wide range of functions in mammals, such as antioxidant, anti-inflammatory, and hypothermic effects among others. However, the influence of acute melatonin administration on human physical performance is debatable. OBJECTIVE: To summarize available data from controlled trials about the effects of acute melatonin administration on human physical performance, especially with respect to strength, power, speed, and short- and long-term continuous exercise. DATA SOURCES: A systematic search of the PubMed, Web of Science, Scopus, Embase, and Cochrane databases up to December 10, 2021, was conducted using specified keywords and Boolean operators ("melatonin" AND "exercise OR circuit-based exercise OR plyometric exercise OR exercise tolerance OR exercise test"). STUDY SELECTION: Only controlled studies in the English language and with humans were accepted. STUDY DESIGN: Systematic review. LEVEL OF EVIDENCE: Level 1. DATA EXTRACTION: Participants' characteristics (sex, age, body mass, height and fat percentage), melatonin dose and administration time, and outcomes from the performance trial were extracted. RESULTS: A total of 10 studies were identified after the screening process. Overall, melatonin did not change speed or short-term continuous exercise performances. However, in relation to strength and power, the results are debatable since 5 articles showed no difference, while another 2 pointed to a decrease in performance. In terms of performance improvement, only 1 study reported an increase in balance and another in long-term continuous exercise performance in nonathletes, with no advantage found for athletes. CONCLUSION: Melatonin did not cause any significant change in strength, speed, power, and short-term continuous exercise performances. In fact, it led to reduced strength and power performances in specific tests. On the other hand, melatonin seems to have improved balance and long-term continuous exercise performance, at least in nonathletes. More investigations are required to corroborate these findings.


Asunto(s)
Melatonina , Humanos , Melatonina/farmacología , Ejercicio Físico , Terapia por Ejercicio/métodos , Fuerza Muscular , Prueba de Esfuerzo
4.
Appl Physiol Nutr Metab ; 48(10): 719-729, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37384946

RESUMEN

Athymic mice are unable to produce T-cells and are then characterized as immunodeficient. This characteristic makes these animals ideal for tumor biology and xenograft research. New non-pharmacological therapeutics are required owing to the exponential increase in global oncology costs over the last 10 years and the high cancer mortality rate. In this sense, physical exercise is regarded as a relevant component of cancer treatment. However, the scientific community lacks information regarding the effect of manipulating training variables on cancer in humans, and experiments with athymic mice. Therefore, this systematic review aimed to address the exercise protocols used in tumor-related experiments using athymic mice. The PubMed, Web of Science, and Scopus databases were searched without restrictions on published data. A combination of key terms such as athymic mice, nude mice, physical activity, physical exercise, and training was used. The database search retrieved 852 studies (PubMed, 245; Web of Science, 390; and Scopus, 217). After title, abstract, and full-text screening, 10 articles were eligible. Based on the included studies, this report highlights the considerable divergences in the training variables adopted for this animal model. No studies have reported the determination of a physiological marker for intensity individualization. Future studies are recommended to explore whether invasive procedures can result in pathogenic infections in athymic mice. Moreover, time-consuming tests cannot be applied to experiments with specific characteristics such as tumor implantation. In summary, non-invasive, low-cost, and time-saving approaches can suppress these limitations and improve the welfare of these animals during experiments.

5.
Healthcare (Basel) ; 11(5)2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36900728

RESUMEN

Colorectal cancer (CRC) burden across the world is expected to increase by ~2.2 million new cases and ~1.1 million deaths by 2030. Regular physical exercise is recommended to prevent CRC, but the myriad of protocols preclude further discussion on how to manage its variables for this population. Home-based exercise guided by remote monitoring provides an alternative to surpass the barriers of supervised exercise. However, no meta-analysis was conducted to verify the effectiveness of this intervention for improving physical activity (PA). We performed a systematic review of remote and unsupervised strategies imposed on CRC patients for improving PA and compared, via a meta-analysis, their effectiveness against CRC patients submitted to usual care or no intervention. The databases PubMed, Scopus, and Web of Science were searched on 20 September 2022. Eleven studies attained the criteria for eligibility in the qualitative approach, and seven were included in the meta-analysis. No significant effect (p = 0.06) of remote and unsupervised exercise intervention was observed. However, a sensitivity analysis including three studies that only considered CRC patients was performed, demonstrating a significant effect in favor of exercise (p = 0.008). Based on our sensitivity analysis, remote and unsupervised exercise strategies were effective to improve the PA of CRC patients.

6.
Biology (Basel) ; 11(12)2022 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-36552244

RESUMEN

The main aim of this study was to compare the performance over different distances, the critical velocity (CV), and plasma acylcarnitines/amino acids of male and female adolescent swimmers. Moreover, we applied the complex network approach to identify which molecules are associated with athletes' performances. On the first day under a controlled environment, blood samples were collected after 12 h of overnight fasting. Performance trials (100, 200, 400, and 800-m) were randomly performed in the subsequent four days in a swimming pool, and CV was determined by linear distance versus time mathematical function. Metabolomic analyses were carried out on a triple quadrupole mass spectrometer performing electrospray ionization in the positive ionization mode. No difference was observed between the performance of male and female swimmers. Except for 200-m distance (p = 0.08), plasma tyrosine was positively and significantly associated with the female times during the trials (100-m, p = 0.04; 400-m, p = 0.04; 800-m, p = 0.02), and inversely associated with the CV (p = 0.02). The complex network approach showed that glycine (0.406), glutamine (0.400), arginine (0.335), free carnitine (0.355), tryptophan (0.289), and histidine (0.271) were the most influential nodes to reach tyrosine. These results revealed a thread that must be explored in further randomized/controlled designs, improving the knowledge surrounding nutrition and the performance of adolescent swimmers.

7.
Front Physiol ; 13: 948422, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36091363

RESUMEN

Although the link between sleep and hematological parameters is well-described, it is unclear how this integration affects the swimmer's performance. The parameters derived from the non-invasive critical velocity protocol have been extensively used to evaluate these athletes, especially the aerobic capacity (critical velocity-CV) and the anaerobic work capacity (AWC). Thus, this study applied the complex network model to verify the influence of sleep and hematological variables on the CV and AWC of young swimmers. Thirty-eight swimmers (male, n = 20; female, n = 18) completed five experimental evaluations. Initially, the athletes attended the laboratory facilities for venous blood collection, anthropometric measurements, and application of sleep questionnaires. Over the 4 subsequent days, athletes performed randomized maximal efforts on distances of 100, 200, 400, and 800-m. The aerobic and anerobic parameters were determined by linear function between distance vs. time, where CV relates to the slope of regression and AWC to y-intercept. Weighted but untargeted networks were generated based on significant (p < 0.05) correlations among variables regardless of the correlation coefficient. Betweenness and eigenvector metrics were used to highlight the more important nodes inside the complex network. Regardless of the centrality metric, basophils and red blood cells appeared as influential nodes in the networks with AWC or CV as targets. The role of other hematologic components was also revealed in these metrics, along with sleep total time. Overall, these results trigger new discussion on the influence of sleep and hematologic profile on the swimmer's performance, and the relationships presented by this targeted complex network can be an important tool throughout the athlete's development.

8.
Front Physiol ; 13: 943498, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36091383

RESUMEN

This study comprises two complementary experiments with athymic Balb/c (Nu/Nu) mice. In experiment 1, the aim was to verify the reproducibility of the peak velocity (VPeak) determined from the incremental test. The second experiment aimed to assess the VPeak sensitivity to prescribe and detect modulations of the physical training in athymic nude mice. Sixteen mice were submitted to two incremental treadmill tests separated by 48-h (Experiment 1). The test consisted of an initial warm-up of 5 minutes. Subsequently, animals initiated the tests at 8 m min-1 with increments of 2 m min-1 every 3 minutes. The VPeak was determined as the highest velocity attained during the protocol. In experiment 2, these animals were randomly allocated to an exercise group (EG) or a control group (CG). The training protocol consisted of 30-min of treadmill running at 70% of the VPeak five times a week for 4 weeks. High indexes of reproducibility were obtained for VPeak (Test = 19.7 ± 3.6 m min-1; Retest = 19.2 ± 3.4 m min-1; p = 0.171; effect size = 0.142; r = 0.90). Animals from the EG had a significant increase of VPeak (Before = 18.4 ± 2.7 m min-1; After = 24.2 ± 6.0 m min-1; p = 0.023). Conversely, a significant decrease was observed for the CG (Before = 21.1 ± 3.9 m min-1; After = 15.9 ± 2.7 m min-1; p = 0.038). The VPeak is a valid parameter for exercise prescription in studies involving athymic nude mice.

9.
Medicine (Baltimore) ; 101(33): e28185, 2022 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-35984148

RESUMEN

The severe acute respiratory syndrome coronavirus has implicated on mental health and psychopathological sequelae through viral infection. Suggestively, the pandemic-associated stressors (e.g., isolation, fear of illness, inadequate information and supply) may affect the sleep and feedback the depression symptoms, ultimately decreasing the immune system and offering further opportunities for severe acute respiratory syndrome coronavirus infection. Nevertheless, this association still requires investigation. Therefore, this study aimed to correlate the depression symptoms with sleep variables from subjects facing the restrictions of the ongoing pandemic in Brazil. One hundred sixty-two volunteers (age = 31 ± 13 years; body mass = 69.8 ± 14.9 kg; height = 168 ± 9 cm) answered the Beck Depression Inventory, Pittsburgh Sleep Quality Index/Epworth Sleepiness Scale for determination of depression symptoms and sleep variables, respectively. Significant and positive correlations were obtained between Beck score and sleep quality (r = 0.53; P = .000), sleep latency (r = 0.29; P = .000), and sleepiness (r = 0.22; P = .003), but not with sleep time (r = -0.10; P = .175). This report concluded that Brazilians struggling with pandemic-associated stressors with high depression symptoms may have negative impacts on sleep, mainly regarding its quality, latency, and sleepiness.


Asunto(s)
COVID-19 , Pandemias , Adolescente , Adulto , Brasil/epidemiología , COVID-19/epidemiología , Depresión/complicaciones , Depresión/epidemiología , Humanos , Sueño , Calidad del Sueño , Somnolencia , Encuestas y Cuestionarios , Adulto Joven
10.
Sci Rep ; 12(1): 2471, 2022 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-35169171

RESUMEN

This systematic review and meta-analysis of randomized controlled trials tested the effects of home-based, supervised, or mixed exercise interventions on the functional capacity (FC) and quality of life (QoL) in colorectal cancer patients. A literature search was performed using the PubMed, Embase, Cochrane, and Medline databases. Two reviewers screened the literature through March 10, 2021 for studies related to exercise and colorectal cancer. Of the 1161 screened studies in the initial search, 13 studies met the eligibility criteria (home-based = 6 studies; supervised or mixed = 7 studies). Overall, 706 patients were enrolled in the trials, and 372 patients were submitted to home-based, supervised, or mixed exercise intervention. The overall results from the main meta-analysis showed a significant effect regarding supervised or mixed intervention (6 studies; p = 0.002; I2 = 43%; PI 0.41-1.39); however, no significant effect was observed for home-based intervention (5 studies; p = 0.05; I2 = 25%; PI - 0.34-0.76). A sensitivity analysis based on studies with intervention adherence ≥ 80% (home-based = 3 studies; supervised or mixed = 4 studies) revealed that home-based intervention or intervention entirely supervised or with some level of supervision (mixed) are effective in improving the QoL and FC of CRC patients. In summary, this meta-analysis verified that supervised and home-based exercise can modify QoL and FC when intervention adherence ≥ 80%. Regardless of the supervision characteristics, future RCTs are strongly encouraged to provide a detailed description of the exercise variables in physical interventions for CRC prescription. This perspective will allow a refined exercise prescription for patients with CRC, mainly according to their clinical status.


Asunto(s)
Neoplasias Colorrectales/rehabilitación , Terapia por Ejercicio/métodos , Servicios de Atención de Salud a Domicilio , Organización y Administración , Calidad de Vida , Recuperación de la Función , Neoplasias Colorrectales/fisiopatología , Femenino , Humanos , Masculino
11.
Front Physiol ; 12: 734806, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34867443

RESUMEN

This study aimed to systematically review studies that evaluated and compared mechanical, physiological, and technical parameters with the performance of slalom athletes. PubMed, SPORTDiscuss, and Scopus databases were searched until September 10, 2021, with no restriction of published data. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guided the study's screening and quality assessment performed by an external reviewer using a 16-checklist item. A search of the databases identified 125 studies, but only eight were eligible, including a total sample of 117 male athletes. Four reports only associated mechanical or technical parameters with the performance of the paddler. Concerning the remaining studies, only one correlated physiological data, and the others associated more than one parameter with race time. Most of the eligible reports presented significant associations between mechanical/physiological components and slalom performance. Eligible studies support that high-force development during a slalom race is a relevant parameter for performance. Aerobic metabolism is highly required during slalom tasks and is inversely associated with race time, although it may not increase the chances of winning medals. Few reports have associated canoe slalom performance with technical components, and further research should focus on this matter.

12.
PLoS One ; 15(8): e0237310, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32785289

RESUMEN

This study aimed to investigate and compare the effects of preferred music on anaerobic threshold determination in an incremental running test, as well the physiological responses and perceived exertion at this intensity, in physically active men and women. Additionally, by using area under the curve (AUC) analysis of the parameters of interest during the graded test, we studied the effects of music at two physiological moments-before and after anaerobic threshold intensity (iAT)-in men and women. Twenty (men = 10; women = 10) healthy and active participants completed four visits to the laboratory. The first and second sessions were used for sample characterization. In the third and fourth sessions, participants performed an incremental running test (started at 7 km.h-1 with increments of 1 km.h-1 at each 3-minute stage) under preferred music and non-music conditions. Blood lactate ([Lac]), heart rate (HR), and perceived exertion were measured by two scales (RPEBorg and the estimation of time limit ‒ ETL) during all tests, and the total time of effort (TT) was considered as performance. Individual curves of the "intensity vs blood lactate" analyzed by the bissegmentation method provide the iAT and the AUC of [Lac], HR, RPEBorg, and ETL before and after the iAT attainment were calculated. The iAT for men (non-music: 11.5±0.9km.h-1 vs music: 11.6±1.1km.h-1) and women (non-music: 9.8±0.7km.h-1 vs music: 9.7±0.7km.h-1) was not affected by music, and for both sexes, there was no difference between non-music and music conditions in all variables obtained at iAT. The AUC of all variables were not affected by music before the iAT attainment. However, [Lac], HR, and RPEBorg presented higher values of AUC after iAT for the female group with preferred music. This may be due to the fact that 70% of women have increased TT under music conditions. Overall, preferred music did not affect the iAT determination in an incremental running test. However, some physiological responses and perceived exertion after iAT of female subjects seems to be influenced by preferred music.


Asunto(s)
Umbral Anaerobio , Música , Carrera , Adulto , Femenino , Frecuencia Cardíaca , Humanos , Ácido Láctico/sangre , Masculino , Resistencia Física , Esfuerzo Físico , Adulto Joven
14.
Int J Sports Med ; 41(7): 450-460, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32396967

RESUMEN

This study aimed to investigate the relationship between mechanical parameters from the Running-based Anaerobic Sprint Test (RAST2×17.5), agility performance from the Illinois Agility Test (IAT) and all-out 30-second tethered running (AO30) in college futsal athletes. It also investigates whether these protocols are capable of identifying differences between sexes. Twenty subjects were evaluated. The IAT was applied on a specific course and performance was considered as the total time (T.T). The RAST2×17.5 consisted of six maximum efforts in a shuttle exercise of 2x17.5 m per bout. The AO30 was conducted under maximal effort on a non-motorized treadmill. Maximum, mean and minimum power were determined for RAST2×17.5 and AO30. Mean power from RAST2×17.5 was inversely and significantly correlated to T.T regardless of sex (male: r=-0.76; p=0.010; female: r=-0.89; p=0.010). A similar association was noticed for maximum power for females (r=-0.94; p=0.001). The AO30 maximum and mean power were significantly correlated with T.T (male: r=-0.67; p=0.031 and r=-0.66; p=0.035, respectively; female: r=-0.64; p=0.046 and r=0.66; p=0.035, respectively). Maximum power from RAST2×17.5 and AO30 were significantly correlated (male: r=0.68; p=0.030; female: r=0.72; p=0.019). Our results reinforce the adoption of field-based tests like RAST2×17.5 and IAT for futsal, since significant relationships among these parameters and AO30 results were obtained. Moreover, these protocols differentiated male and female athletes by mechanical and agility parameters, proving their application under specific field evaluation.


Asunto(s)
Rendimiento Atlético/fisiología , Prueba de Esfuerzo/métodos , Destreza Motora/fisiología , Deportes/fisiología , Rendimiento Atlético/psicología , Femenino , Humanos , Masculino , Consumo de Oxígeno , Carrera/fisiología , Factores Sexuales , Deportes/psicología
15.
Front Physiol ; 11: 617041, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33551845

RESUMEN

This study aimed to compare the aerobic power (treadmill running) and muscle power (bench press and bench pull) of Junior/U23 paddlers from Slovakia who won medals in international championships with that of those who did not take the podium. Forty-three Slovak Junior/U23 paddlers (sprint = 24, medalists = 8, non-medalists = 16; slalom = 19, medalists = 11, non-medalists = 8) were tested in 2018 and 2019 after the world championships. The maximal oxygen uptake (VO2max) and the velocity at maximal oxygen uptake (vVO2max) were determined by the incremental running protocol (0% slope and 1 km⋅h-1 increments every minute until volitional exhaustion). Mean maximal power from the entire concentric phase was recorded during bench press and bench pull exercises by the validated TENDO weightlifting analyzer. No interaction was obtained between medal and canoe discipline for VO2max (p = 0.069, F = 3.495), vVO2max (p = 0.552, F = 0.361) and absolute (bench press: p = 0.486, F = 0.495; bench pull: p = 0.429, F = 0.640) or relative (bench press: p = 0.767, F = 0.089; bench pull: p = 0.696, F = 0.155) mean maximal power. Conversely, a significant effect for the medal on the bench press (absolute p = 0.017, F = 6.170; relative p = 0.043, F = 4.384) and the bench pull (absolute p = 0.041, F = 4.470) mean maximal power were observed. Our study indicates the absolute mean power on the bench press as a prerequisite for success in international Junior/U23 championships of slalom and sprint canoeing. However, the mean power on bench pull seems to have a deeper influence on sprint paddlers when compared to slalom athletes. Regarding the aerobic power, the data from the treadmill testing did not reveal outcomes between medalists and non-medalists. This result can be associated with the lack of specificity of the incremental treadmill testing for canoeing, and future studies are encouraged to propose specific protocols to compare the aerobic power of medalists and non-medalists in international slalom and sprint championships.

16.
Neuroscience ; 427: 64-74, 2020 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-31887360

RESUMEN

Regular physical exercise has been described as a good strategy for prevention or reduction of musculoskeletal pain. The Peroxisome Proliferator-Activated Receptor Gamma (PPARγ) has been investigated as a promising target for the control of inflammatory pain. Therefore, the aim of this study was to evaluate whether activation of PPARγ receptors is involved in the reduction of acute muscle pain by chronic exercise and, in this case, whether this process is modulated by inflammatory cytokines. To this end, Wistar rats were submitted to swimming physical training for a period of 10 weeks, 5 days per week, 40 min/day, in an intensity of 4% of the body mass. Muscle hyperalgesia was measured by Randall Selitto test and pro-inflammatory cytokines were quantified by ELISA. The results showed that swimming physical training prevented the onset of acute mechanical muscle hyperalgesia and the increase in muscle levels of Cytokine-induced neutrophil chemoattractant 1 (CINC-1) induced by carrageenan into gastrocnemius muscle. In addition, local pre-treatment with the selective PPARγ receptors antagonist GW9662 reversed the mechanical muscle hypoalgesia and the modulation of CINC-1 levels induced by swimming physical training. These data suggest that swimming physical training prevented the onset of acute mechanical muscle hyperalgesia by a mechanism dependent of PPARγ receptors, which seems to contribute to this process by modulation of the pro-inflammatory cytokine CINC-1, and highlight the potential of PPARγ receptors as a target to control musculoskeletal pain and to potentiate the reduction of musculoskeletal pain induced by exercise.


Asunto(s)
Quimiocina CXCL1/metabolismo , Hiperalgesia/prevención & control , Mialgia/prevención & control , PPAR gamma/metabolismo , Natación/fisiología , Anilidas/farmacología , Animales , Citocinas/metabolismo , Masculino , Mialgia/inducido químicamente , Mialgia/metabolismo , Nocicepción/efectos de los fármacos , Nocicepción/fisiología , Ratas , Ratas Wistar
17.
PLoS One ; 13(3): e0194313, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29534108

RESUMEN

Our first aim was to compare the anaerobic threshold (AnT) determined by the incremental protocol with the reverse lactate threshold test (RLT), investigating the previous cycling experience effect. Secondarily, an alternative RLT application based on heart rate was proposed. Two groups (12 per group-according to cycling experience) were evaluated on cycle ergometer. The incremental protocol started at 25 W with increments of 25 W at each 3 minutes, and the AnT was calculated by bissegmentation, onset of blood lactate concentration and maximal deviation methods. The RLT was applied in two phases: a) lactate priming segment; and b) reverse segment; the AnT (AnTRLT) was calculated based on a second order polynomial function. The AnT from the RLT was calculated based on the heart rate (AnTRLT-HR) by the second order polynomial function. In regard of the Study 1, most of statistical procedures converged for similarity between the AnT determined from the bissegmentation method and AnTRLT. For 83% of non-experienced and 75% of experienced subjects the bias was 4% and 2%, respectively. In Study 2, no difference was found between the AnTRLT and AnTRLT-HR. For 83% of non-experienced and 91% of experienced subjects, the bias between AnTRLT and AnTRLT-HR was similar (i.e. 6%). In summary, the AnT determined by the incremental protocol and RLT are consistent. The AnT can be determined during the RLT via heart rate, improving its applicability. However, future studies are required to improve the agreement between variables.


Asunto(s)
Umbral Anaerobio/fisiología , Prueba de Esfuerzo/métodos , Ejercicio Físico/fisiología , Ácido Láctico/sangre , Adulto , Ciclismo/fisiología , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Modelos Biológicos , Resistencia Física/fisiología , Adulto Joven
18.
PLoS One ; 13(2): e0192835, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29489872

RESUMEN

This study was divided into two complementary parts. In Part 1, we proposed a novel paddle strokes analysis based on the force signal from a 30-s all-out tethered test; and compared these results with video recordings. In Part 2, we investigated the relationship between force data from the same test with paddle stroke results from both methods. Eleven male elite slalom kayakers (Brazilian national team) were evaluated. The tethered test was conducted for force parameters analysis (peak-force, mean-force, impulse). Video recording analysis was conducted, and the performed strokes (V.NumberPaddle) was counted and frequency (V.FrequencyPaddle) calculated by the V.NumberPaddle divided by 30 (i.e. total time of test). The new method consisted of performed strokes and frequency achievement from a load cell force signal analysis (S.NumberPaddle and S.FrequencyPaddle, respectively). Paired test-t did not show difference between methods results, but significant correlations were only obtained for the number of paddle strokes. Force parameters were only correlated with S.NumberPaddle and S.FrequencyPaddle. Overall, considering the theoretical and practical application, we propose that the new method should be used as an alternative to the video recording.


Asunto(s)
Ergometría/métodos , Deportes Acuáticos/fisiología , Aceleración , Adolescente , Fenómenos Biomecánicos , Interpretación Estadística de Datos , Ergometría/estadística & datos numéricos , Humanos , Masculino , Fuerza Muscular , Grabación en Video , Adulto Joven
19.
Motriz (Online) ; 24(2): e1018169, 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-895063

RESUMEN

Aims: This study is aimed at testing the acute melatonin administration (oral; 6 mg) on aerobic tolerance at cycloergometer and analyzing the consequences on biochemical and hematological parameters. Methods: The maximal aerobic capacity intensity (iMAC) at cycloergometer of eleven male healthy men (24.18±3.92 years-old; 87.07±12.48 kg; 1.82±0.05 m; 26.18±3.63 kg/m2; and 16.28±5.77 % of fat) was individually determined and used to perform a time to exhaustion (tlim) trial of 30 minutes after melatonin or placebo administration. We observed 48-72h interval between tests, performed in a double-blind experiment design. In order to determine hematological and biochemical parameters we collected venous blood samples before and after tlim. Statistical significance was set at 5%. Results The intensity and the lactatemia corresponding to the maximal aerobic capacity were 120.88±18.78 W and 3.32±1.03 mmol.L-1, respectively. The tlim with placebo (33.94±15.26 min, confidence interval = 24.92 - 42.95) was significantly lower than the tlim with melatonin (41.94±17.22 min; CI = 31.76 - 52.12; p = 0.03; 19.06%; effect size = 0.49). All of the 21 analyzed blood physiological variables resulted in no significant variation after tlim when placebo was compared to melatonin, except for total sera cholesterol (lower after exercise with melatonin). Conclusion: Acute melatonin administration enhanced aerobic tolerance at iMAC in 19% at cycloergometer; however, the biochemical and hematological variables assessed were not significantly modulated.(AU)


Asunto(s)
Humanos , Masculino , Adulto , 5-Metoxitriptamina/metabolismo , Ejercicio Físico/fisiología , Melatonina/administración & dosificación , Consumo de Oxígeno/fisiología , Capacidad Vital
20.
Motriz (Online) ; 24(2): e101858, 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-955136

RESUMEN

Abstract AIMS The aims of this study were to investigate and characterize the anthropometric, nutritional, genetic, psychological and sleep variables of slalom kayakers, and to verify the correlation of these variables with the slalom kayakers' performance. METHODS Ten elite Brazilian team slalom kayakers participated of this study. Nutritional analysis was made by the Food Record (three days), 24 Hour Dietary Recall and Food Frequency Questionnaire. The ACE I/D, AGTMet235Thr, ACTN3R577X and BDKRB2+9/-9 were genotyped for genetic profile. The Profile of Mood States (POMS) and Sports Competition Anxiety Test (SCAT) were applied to investigate the psychological variables. The Pittsburgh Sleep Quality Index (PSQI), Epworth Sleep Scale (ESS) and Morningness-eveningness questionnaire (MEQ) were used for sleep traits analysis. Performance trials were performed on a white-water course with 24 gates, and finish time was considered as the variable related to performance. RESULTS Significant correlations were obtained between Performance Time Trial and %Fat (r=0.77), Energy (r=-0.75), Protein (r=-0.76), Carbohydrate (r=-0.72), Vitamin B6 (r=-0.87), Vitamin A (r=-0.82), Thiamine (r=-0.77), Riboflavin (r=-0.71), Magnesium (r=-0.86) and Phosphorus (r=-0.74) intake, besides the Fatigue mood domain (r=0.73) and the SCAT score (r=0.67). Athletes genotyped with the I, T, R and +9 alelle also presented better performances. CONCLUSIONSIn summary, the novel results provided by this study reinforce the necessity of considering several aspects during athlete development in order to achieve better performance in competitions.


Asunto(s)
Humanos , Rendimiento Atlético , Atletas/psicología , Deportes Acuáticos , Sueño , Escala de Ansiedad ante Pruebas , Evaluación Nutricional , Antropometría/instrumentación
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