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1.
Int J Sports Physiol Perform ; 19(7): 696-704, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38772546

RESUMO

PURPOSE: This cohort study aimed to investigate the relationship between subjective (wellness and internal training load [ITL]) and objective (neuromuscular fatigue) monitoring markers and performance aspects (reception quality [RQ] and attack efficiency [AE]) in professional female volleyball players. METHODS: The study was conducted over an 8-week period during the final mesocycle of the competitive phase. A total of 24 training sessions and 10 matches were included in the analysis. Subjective measures of wellness and ITL were assessed, and neuromuscular fatigue was evaluated using countermovement-jump (CMJ) height. RQ and AE were determined based on game statistics. RESULTS: The study found a positive relationship between wellness and RQ, particularly affecting outside hitters and liberos. ITL showed a positive association with AE, primarily impacting outside hitters, opposite hitters, and middle blockers. Additionally, ITL demonstrated a negative correlation with RQ, mainly affecting outside hitters and liberos. CMJ performance was associated with AE, where a decrease in CMJ height was linked to reduced AE. CONCLUSIONS: The findings highlight the importance of considering players' wellness scores in training and match strategies for different positions. Careful management of training loads, considering both physical and technical demands, is crucial for optimizing performance outcomes. Monitoring neuromuscular fatigue, as indicated by CMJ performance, is particularly relevant for outside hitters, opposite hitters, and middle blockers involved in attack actions. Coaches, trainers, and sports practitioners can use these insights to develop position-specific training protocols and implement effective strategies for maintaining or improving performance metrics under various stressors.


Assuntos
Desempenho Atlético , Fadiga Muscular , Voleibol , Humanos , Feminino , Voleibol/fisiologia , Desempenho Atlético/fisiologia , Fadiga Muscular/fisiologia , Adulto Jovem , Condicionamento Físico Humano/métodos , Comportamento Competitivo/fisiologia , Adulto , Nível de Saúde , Estudos de Coortes
2.
Sports (Basel) ; 12(2)2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38393272

RESUMO

Research on the evolution of performance throughout a season in team sports is scarce and mainly focused on men's teams. Our aim in this study was to examine the seasonal variations in relevant indices of physical performance in female football players. Twenty-seven female football players were assessed at week 2 of the season (preseason, PS), week 7 (end of preseason, EP), week 24 (half-season, HS), and week 38 (end of season, ES). Similar to the most common used conditioning tests in football, testing sessions consisted of (1) vertical countermovement jump (CMJ); (2) 20 m running sprint (T20); (3) 25 m side-step cutting maneuver test (V-CUT); and (4) progressive loading test in the full-squat exercise (V1-LOAD). Participants followed their normal football training procedure, which consisted of three weekly training sessions and an official match, without any type of intervention. No significant time effects were observed for CMJ height (p = 0.29) and T20 (p = 0.11) throughout the season. However, significant time effects were found for V-CUT (p = 0.004) and V1-LOAD (p = 0.001). V-CUT performance significantly improved from HS to ES (p = 0.001). Significant increases were observed for V1-LOAD throughout the season: PS-HS (p = 0.009); PS-ES (p < 0.001); EP-ES (p < 0.001); and HS-ES (p = 0.009). These findings suggest that, over the course of the season, female football players experience an enhancement in muscle strength and change of direction ability. However, no discernible improvements were noted in sprinting and jumping capabilities during the same period.

3.
J Cogn ; 7(1): 23, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38380075

RESUMO

Despite the abundance of research evaluating working memory training outcomes in children, few studies have examined the underlying cognitive mechanisms. This study aimed to contribute understanding by exploring whether working memory capacity (maximum span) and/or efficiency (basic and cognitive processing speeds), two proposed cognitive mechanisms, are associated with children's working memory performance immediately and 6-months post-intervention. We used data from a previous trial in primary school children (7-11 years) who completed working memory training (n = 52) or an active control (n = 36), comprising 10 sessions (each 20-minutes) in class over two weeks. Children completed five working memory measures at baseline, immediately and 6-months post-intervention: two Backwards Span and two Following Instructions measures (same paradigms as training activities), and one n-back measure (different paradigm). Maximum span, basic and cognitive processing speeds, and performance were calculated for each measure. Associations between change in maximum span, processing speeds and change in performance on the working memory measures from baseline to immediately and 6-months post-intervention did not differ between groups (all p < .05). Maximum span, processing speeds and performance on working memory measures did not differ between groups. Findings provide little evidence that the studied capacity or efficiency processes contribute to understanding working memory training outcomes in primary school children. Furthermore, working memory training did not have benefits for children's working capacity, efficiency or performance up to 6-months post-intervention. It is of interest for future studies to explore cognitive mechanisms, including strategy use, maximum span and information processing, in datasets where training effects are observed.

4.
Sports (Basel) ; 12(1)2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38251291

RESUMO

Different training intensity distributions (TIDs) have been proposed to improve cycling performance, especially for high-competition athletes. The objectives of this study were to analyze the effect of a 16-week pyramidal training intensity distribution on somatic and power variables in recreational cyclists and to explore the training zone with the greatest impact on performance improvement. The sample consisted of 14 male recreational cyclists aged 41.00 ± 7.29 years of age. A number of somatic variables were measured. During an incremental protocol, power at a 4 mMol·L-1 blood lactate concentration (P4), corresponding power to body mass ratio (P/W P4), and heart rate (HR P4) were also measured. Among the somatic variables, the percentage of fat mass showed the greatest improvement between moments (p < 0.001, d = 0.52). Both P4 (p < 0.001, d = 1.21) and P/W P4 (p < 0.001, d = 1.54) presented a significant increase between moments. The relative improvement in P4 (% P4) showed a significant correlation (Rs = 0.661, p = 0.038) and relationship (R2 = 0.61, p = 0.008) mainly with training zone Z2 (blood lactate levels ≥ 2 and <4 mMol·L-1). It seems that spending more time in Z2 promoted an improvement in both somatic and power variables in recreational cyclists.

5.
JMIR Res Protoc ; 12: e47496, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37725418

RESUMO

BACKGROUND: A common yet untested assumption of cognitive training in children is that activities should be adaptive, with difficulty adjusted to the individual's performance in order to maximize improvements on untrained tasks (known as transfer). Working memory training provides the ideal testbed to systematically examine this assumption as it is one of the most widely studied domains in the cognitive training literature, and is critical for children's learning, including following instructions and reasoning. OBJECTIVE: This trial aimed to examine children's outcomes of working memory training using adaptive, self-select (child selects difficulty level), and stepwise (difficulty level increases incrementally) approaches to setting the difficulty of training activities compared to an active control condition immediately and 6-month postintervention. While the aim is exploratory, we hypothesized that children allocated to a working memory training condition would show greater improvements: (1) on near transfer measures compared to intermediate and far transfer measures and (2) immediately postintervention compared to 6-month postintervention. METHODS: This double-blinded, active-controlled, parallel-group randomized trial aimed to recruit 128 children aged 7 to 11 years from 1 metropolitan primary school in Melbourne, Australia. Following baseline testing, children were randomized into 1 of 4 conditions: adaptive, self-select, or stepwise working memory training, or active control. An experimental intervention embedded in Minecraft was developed for teachers to deliver in class over 2 consecutive weeks (10 × 20-minute sessions). The working memory training comprised 2 training activities with processing demands similar to daily activities: backward span and following instructions. The control comprised creative activities. Pre- and postintervention, children completed a set of working memory tests (near and intermediate transfer) and the Raven's Standard Progressive Matrices (far transfer) to determine training outcomes, as well as motivation questionnaires to determine if motivations toward learning and the intervention were similar across conditions. Caregivers completed the ADHD-Rating Scale-5 to measure their child's attention (far transfer). Statistical analysis will include traditional null hypothesis significance testing and Bayesian methods to quantify evidence for both the null and alternative hypotheses. RESULTS: Data collection concluded in December 2022. Data are currently being processed and analyzed. CONCLUSIONS: This trial will determine whether the adaptive approach to setting the difficulty of training activities maximizes cognitive training outcomes for children. This trial has several strengths: it adopts best practices for cognitive training studies (design, methods, and analysis plan); uses a range of measures to detect discrete levels of transfer; has a 6-month postintervention assessment; is appropriately powered; and uses an experimental working memory training intervention based on our current understanding of the cognitive mechanisms of training. Findings will inform future research and design of cognitive training interventions and highlight the value of the evidence-based principles of cognitive training. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry, ACTRN12621000990820; https://www.anzctr.org.au/ACTRN12621000990820.aspx. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/47496.

6.
JMIR Form Res ; 7: e44857, 2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37103996

RESUMO

BACKGROUND: Social skills training by human trainers is a well-established method of teaching appropriate social and communication skills and strengthening social self-efficacy. Specifically, human social skills training is a fundamental approach to teaching and learning the rules of social interaction. However, it is cost-ineffective and offers low accessibility, since the number of professional trainers is limited. A conversational agent is a system that can communicate with a human being in a natural language. We proposed to overcome the limitations of current social skills training with conversational agents. Our system is capable of speech recognition, response selection, and speech synthesis and can also generate nonverbal behaviors. We developed a system that incorporated automated social skills training that completely adheres to the training model of Bellack et al through a conversational agent. OBJECTIVE: This study aimed to validate the training effect of a conversational agent-based social skills training system in members of the general population during a 4-week training session. We compare 2 groups (with and without training) and hypothesize that the trained group's social skills will improve. Furthermore, this study sought to clarify the effect size for future larger-scale evaluations, including a much larger group of different social pathological phenomena. METHODS: For the experiment, 26 healthy Japanese participants were separated into 2 groups, where we hypothesized that group 1 (system trained) will make greater improvement than group 2 (nontrained). System training was done as a 4-week intervention where the participants visit the examination room every week. Each training session included social skills training with a conversational agent for 3 basic skills. We evaluated the training effect using questionnaires in pre- and posttraining evaluations. In addition to the questionnaires, we conducted a performance test that required the social cognition and expression of participants in new role-play scenarios. Blind ratings by third-party trainers were made by watching recorded role-play videos. A nonparametric Wilcoxson Rank Sum test was performed for each variable. Improvement between pre- and posttraining evaluations was used to compare the 2 groups. Moreover, we compared the statistical significance from the questionnaires and ratings between the 2 groups. RESULTS: Of the 26 recruited participants, 18 completed this experiment: 9 in group 1 and 9 in group 2. Those in group 1 achieved significant improvement in generalized self-efficacy (P=.02; effect size r=0.53). We also found a significant decrease in state anxiety presence (P=.04; r=0.49), measured by the State-Trait Anxiety Inventory (STAI). For ratings by third-party trainers, speech clarity was significantly strengthened in group 1 (P=.03; r=0.30). CONCLUSIONS: Our findings reveal the usefulness of the automated social skills training after a 4-week training period. This study confirms a large effect size between groups on generalized self-efficacy, state anxiety presence, and speech clarity.

7.
Int J Sports Physiol Perform ; 18(5): 474-487, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36927997

RESUMO

PURPOSE: To examine the construct validity and reliability of 2 single items for fatigue and recovery in dancers. The construct validity was assessed using reference instruments: the fatigue items of the Brunel Mood Scale (BRUMS) and the Short Recovery and Stress Scale (SRSS). A secondary aim was to explore the respondent interpretation of these 2 items using a concept identification approach. METHODS: Two hundred forty-three (N = 243) dancers completed single-item fatigue and recovery (unipolar and bipolar), BRUMS, and SRSS once for construct validity. For reliability, 49 dancers completed the questionnaires twice, 1 week apart. Using a concept identification approach, 49 dancers were also asked comprehension and interpretation of fatigue and recovery. RESULTS: The fatigue item correlated with SRSS stress items (rs = .37-.51) and BRUMs fatigue items (rs = .63-.66). The recovery item was only partially confirmed in terms of construct validity, when using the SRSS recovery items as reference (rs = .39-.43). Reliability was confirmed for the single items of fatigue (κ = .77-.78) and recovery (κ = .71-.78). Main responses for the concept of fatigue were tiredness (34.7%), muscle soreness (17.3%), and energy (13.0%). Main responses for the concept of recovery were muscle soreness (43.0%), tiredness (27.9%), and fatigue (24.0%). CONCLUSION: We provide preliminary confirmation of the validity and reliability of the single item fatigue in dancers. The recovery item was only partially confirmed in terms of construct validity, when using the SRSS recovery items as reference, but did display acceptable reliability and agreement. Further research is warranted further exploring other measurement properties.


Assuntos
Afeto , Mialgia , Humanos , Reprodutibilidade dos Testes , Inquéritos e Questionários , Fadiga , Psicometria
8.
Brain Stimul ; 15(6): 1541-1551, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36460294

RESUMO

BACKGROUND: Transcranial direct current stimulation (tDCS) has shown potential as an effective aid to facilitate learning. A popular application of this technology has been in combination with working memory training (WMT) in order to enhance transfer effects to other cognitive measures after training. OBJECTIVE: This meta-analytic review aims to synthesize the existing literature on tDCS-enhanced WMT to quantify the extent to which tDCS can improve performance on transfer tasks after training. Furthermore, we were interested to evaluate the moderating effects of assessment time point (immediate post-test vs. follow-up) and transfer distance, i.e., the degree of similarity between transfer and training tasks. METHODS: Using robust variance estimation, we performed a systematic meta-analysis of all studies to date that compared WMT with tDCS to WMT with sham in healthy adults. All procedures conformed to PRISMA guidelines. RESULTS: Across 265 transfer measures in 18 studies, we found a small positive net effect of tDCS on improving overall performance on transfer measures after WMT. These effects were sustained at follow-up, which ranged from 1 week to one year after training, with a median of 1 month. Additionally, although there were no significant differences as a function of transfer distance, effects were most pronounced for non-trained working memory tasks. CONCLUSIONS: This review provides evidence that tDCS can be effective in promoting learning over and above WMT alone, and can durably improve performance on trained and untrained measures for weeks to months after the initial training and stimulation period. In particular, boosting performance on dissimilar working memory tasks may present the most promising target for tDCS-augmented WMT.


Assuntos
Memória de Curto Prazo , Estimulação Transcraniana por Corrente Contínua , Adulto , Humanos , Memória de Curto Prazo/fisiologia , Estimulação Transcraniana por Corrente Contínua/métodos , Treino Cognitivo , Aprendizagem , Testes Neuropsicológicos , Córtex Pré-Frontal/fisiologia
9.
Sports Med Open ; 8(1): 118, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36114395

RESUMO

For more than a century, many concepts and several theories and principles pertaining to the goals, organization, methodology and evaluation of the effects of resistance training (RT) have been developed and discussed between coaches and scientists. This cumulative body of knowledge and practices has contributed substantially to the evolution of RT methodology. However, a detailed and rigorous examination of the existing literature reveals many inconsistencies that, unless resolved, could seriously hinder further progress in our field. The purpose of this review is to constructively expose, analyze and discuss a set of anomalies present in the current RT methodology, including: (a) the often inappropriate and misleading terminology used, (b) the need to clarify the aims of RT, (c) the very concept of maximal strength, (d) the control and monitoring of the resistance exercise dose, (e) the existing programming models and (f) the evaluation of training effects. A thorough and unbiased examination of these deficiencies could well lead to the adoption of a revised paradigm for RT. This new paradigm must guarantee a precise knowledge of the loads being applied, the effort they involve and their effects. To the best of our knowledge, currently this can only be achieved by monitoring repetition velocity during training. The main contribution of a velocity-based RT approach is that it provides the necessary information to know the actual training loads that induce a specific effect in each athlete. The correct adoption of this revised paradigm will provide coaches and strength and conditioning professionals with accurate and objective information concerning the applied load (relative load, level of effort and training effect). This knowledge is essential to make rational and informed decisions and to improve the training methodology itself.

10.
Artigo em Inglês | MEDLINE | ID: mdl-35564336

RESUMO

Dopamine receptor D2 gene (DRD2) polymorphisms have been associated with cognitive abilities, obesity, addictions, and physical-activity-related behaviors, which may underlie differences in the effectiveness of training programs. What is not yet clear is the impact of DRD2 polymorphisms on the effectiveness of exercise programs. Thus, the aim of this study was to investigate the association between the DRD2 polymorphic sites (rs1076560, rs12364283, rs1799732, rs1800497, and rs1800498) and the body's response to regular physical activity. We studied genotypes and haplotypes distribution in a group of 165 females measured for body mass and body composition measurements, lipid profile, and glucose levels before and after realization of a 12-week training program. When tested individually, statistical analyses revealed one significant genotype by training interaction under the general model (for the basal metabolic rate, BMR, p = 0.033). Carriers of the rs1076560 CC genotype exhibited a decrease in BMR in response to training (p = 0.006). Haplotype analyses also showed that (i) the CACCC and CACTT haplotypes were associated with a post-training decrease in glucose level (ß = -4.11, p = 0.032; ß = -6.86, p = 0.020, respectively); (ii) the CGCCT with an increase in BMR (ß = 0.65, p = 0.003) and fat free mass (FFM, ß = 1.20, p = 0.009); (iii) the CA-CT with a decrease in low-density lipoprotein cholesterol (LDL, ß = -17.26, p = 0.046). These results provide some evidence that the DRD2 polymorphisms may play a role in post-training changes in lipid and carbohydrate metabolism, and, as a consequence, in the effectiveness of training programs.


Assuntos
Condicionamento Físico Humano , Polimorfismo Genético , Receptores de Dopamina D2 , Estudos de Casos e Controles , LDL-Colesterol , Feminino , Genótipo , Glucose , Humanos , Polimorfismo de Nucleotídeo Único , Receptores de Dopamina D2/genética
11.
J Vet Med Educ ; : e20210143, 2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35613302

RESUMO

Veterinary resident training in minimally invasive surgery is currently inconsistent and depends on innate psychomotor skills. Simulation training has been shown to effectively increase basic skills, but demonstration of simulation training effects on advanced skills in the operating room is sparse. We aimed to determine if simulation-trained novice surgeons were able to perform laparoscopic suture ligation in live dogs. Three novice laparoscopic surgeons underwent a 12-session simulation training program with subsequent laparoscopic skills testing to demonstrate competency. The median skills scores of trainees and of one experienced surgeon were 417 and 472, respectively. Eighteen healthy client-owned (shelter) dogs were operated on by four surgeons: one experienced American College of Veterinary Surgeons (ACVS) diplomate, two novice ACVS residents, and one novice ACVS diplomate. Laparoscopic ovariectomy was performed with suture ligation of the ovarian pedicles. Successful surgery was defined as no evidence of ovarian vessel bleeding after transection of the pedicles. Simulation-trained novices performed successful suture-ligated ovariectomies in 11/13 dogs (85%), and the experienced surgeon in 5/5 (100%) dogs. Median total ligation time was 30 minutes (range: 17-57), which was not different among surgeons (p = .118). Median total surgery time was 105 minutes (range: 69-156) for novices and 89 minutes (range: 65-99) for the experienced surgeon (p = .038). Extensive simulation training including suturing may contribute toward surgery residents being able to perform complex laparoscopic procedures. These results need to be confirmed in larger numbers of trainees.

12.
BMC Public Health ; 21(1): 455, 2021 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-33676474

RESUMO

BACKGROUND: Physical activity has positive effects on several diseases and may reduce the risk of morbidity and the mortality rate. Whether the prevalence of disease and health care consumption differ between the members of sports organizations and the general population has not been established. Hence, this pilot study aimed to compare the prevalence of diseases known to be associated with physical inactivity and health care consumption in members of a large non-profit sports organization and an age-, sex- and geographically matched random sample from the general population. METHODS: Subjects in two Swedish cities who exercised at least once a week and had been members for at least two years in the non-profit sports organization Friskis&Svettis were invited. A randomized age-, sex- and geographically matched sample was drawn from the general population. Data on disease prevalence (by International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) codes) and health care consumption were retrieved using the members' personal identification numbers through a regional health care database. Between-group differences in the prevalence of disease were compared using chi2-tests and logistic regression between members and controls. Health care consumption was defined as the number of visits, stratified by primary and hospital care, and was compared using chi2-tests and Mann-Whitney U-tests. RESULTS: In total, 3015 subjects were included in each group (response rate 11%). Controls had higher prevalence rates of musculoskeletal diseases (13.3% vs. 11.6%, p = 0.047), metabolic disease (10.4% vs. 5.4%, p < 0.001), hypertension (16.6% vs. 11.7%, p < 0.001), psychiatric diseases (8.9% vs. 7.1%, p = 0.012) and lung cancer (0.4% vs. 0%, p = 0.001) than the members. The total number of health care contacts was 22% higher in the controls than in the members, whereas the proportion of subjects with at least one health care visit was larger in the members (89% vs. 79%, p < 0.001). CONCLUSIONS: The prevalence rates of lifestyle diseases related to musculoskeletal, metabolic and psychiatric diseases, hypertension and lung cancer, and the overall health care consumption, were lower among members of a sports organization than among controls. However, longitudinal studies are needed to establish a cause-effect relationship between membership and disease development.


Assuntos
Atenção à Saúde , Bases de Dados Factuais , Humanos , Projetos Piloto , Prevalência , Suécia/epidemiologia
13.
Ergonomics ; 64(2): 149-170, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32966161

RESUMO

Within minutes, an incipient fire can develop into a life-threatening full fire. Consequently, it should be fought as early as possible. But are laypersons capable of doing this? In such a situation, how do they behave and feel? These questions are addressed in the current study. Persons without any professional firefighting training (N = 64) were confronted in two experimental runs with a real incipient fire in the form of a burning pillow. The results show that most participants were motivated and able to extinguish the fire successfully. However, most of them made a number of mistakes. Of central importance for extinguishing the fire was self-efficacy. Furthermore, participants improved greatly in the second round, especially regarding reaction time span and various psychological variables (e.g. stress, mood). Particularly on the basis of these exercise effects, we can derive a number of practical implications. Practitioner Summary: Laypersons are willing and able to successfully fight an incipient fire. Yet, their behaviour is not optimal and could lead to self-endangerment. Thus, it is critically important that people perform practical exercises as part of fire safety trainings and repeat them after some time. Abbreviatons: TPB: theory of planned behaviour; CIT: critical incident technique; MANOVA: multivariate analysis of variance.


Assuntos
Prevenção de Acidentes/métodos , Emergências , Medo/psicologia , Incêndios/prevenção & controle , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
14.
Cells ; 9(2)2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-32024023

RESUMO

BACKGROUND: The vascular effects of training under blood flow restriction (BFR) in healthy persons can serve as a model for the exercise mechanism in lower extremity arterial disease (LEAD) patients. Both mechanisms are, inter alia, characterized by lower blood flow in the lower limbs. We aimed to describe and compare the underlying mechanism of exercise-induced effects of disease- and external application-BFR methods. METHODS: We completed a narrative focus review after systematic literature research. We included only studies on healthy participants or those with LEAD. Both male and female adults were considered eligible. The target intervention was exercise with a reduced blood flow due to disease or external application. RESULTS: We identified 416 publications. After the application of inclusion and exclusion criteria, 39 manuscripts were included in the vascular adaption part. Major mechanisms involving exercise-mediated benefits in treating LEAD included: inflammatory processes suppression, proinflammatory immune cells, improvement of endothelial function, remodeling of skeletal muscle, and additional vascularization (arteriogenesis). Mechanisms resulting from external BFR application included: increased release of anabolic growth factors, stimulated muscle protein synthesis, higher concentrations of heat shock proteins and nitric oxide synthase, lower levels in myostatin, and stimulation of S6K1. CONCLUSIONS: A main difference between the two comparators is the venous blood return, which is restricted in BFR but not in LEAD. Major similarities include the overall ischemic situation, the changes in microRNA (miRNA) expression, and the increased production of NOS with their associated arteriogenesis after training with BFR.


Assuntos
Adaptação Fisiológica , Artérias/crescimento & desenvolvimento , Artérias/fisiologia , Exercício Físico , Organogênese , Humanos , Miostatina/metabolismo , Fluxo Sanguíneo Regional
15.
Brain Res Bull ; 152: 52-62, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31302239

RESUMO

Muscarinic antagonist scopolamine has been extensively used to model amnesia in lab rodents, but most studies have focused on the effects of pre-training scopolamine administration. Here, we examined post-training scopolamine administration in C57BL/6JRj mice. Learning was assessed in three different procedures: odour discrimination in a digging paradigm, visual discrimination in a touchscreen-based setup, and spatial learning in the Morris water maze. Scopolamine administration affected performance in the odour discrimination task. More specifically, scopolamine decreased perseverance, which facilitated reversal learning. Similar results were obtained in the visual discrimination task, but scopolamine did not affect performance in the spatial learning task. It is unlikely that these results can be explained by non-memory-related cognitive effects (e.g., attention), non-cognitive behaviours (e.g., locomotor activity) or peripheral side-effects (e.g., mydriasis). They likely relate to the various neuropharmacological actions of scopolamine.


Assuntos
Amnésia/tratamento farmacológico , Aprendizagem/efeitos dos fármacos , Escopolamina/farmacologia , Amnésia/metabolismo , Animais , Discriminação Psicológica/efeitos dos fármacos , Feminino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Antagonistas Muscarínicos/farmacologia , Percepção Olfatória , Reversão de Aprendizagem/efeitos dos fármacos , Escopolamina/metabolismo , Aprendizagem Espacial/efeitos dos fármacos , Percepção Visual
16.
Front Hum Neurosci ; 13: 128, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31057380

RESUMO

Electroencephalography based brain-computer interfaces (BCIs) show promise of providing an alternative communication channel between the brain and an external device. It is well acknowledged that BCI control is a skill and could be improved through practice and training. In this study, we explore the change of BCI behavioral performance as well as the electrophysiological properties across three training sessions in a pool of 42 human subjects. Our results show that the group average of BCI accuracy and the information transfer rate improved significantly in the third session compared to the first session; especially the significance reached in a smaller subset of a low BCI performance group (average accuracy <70%) as well. There was a significant difference of event-related desynchronization (ERD) lateralization for BCI control between the left- and right-hand imagination task in the last two sessions, but this significant difference was not revealed in the first training sessions. No significant change of R 2 value or event-related desynchronization and synchronization (ERD/ERS) for either channel C3 or channel C4, which were used for online control, was found across the training sessions. The change of ERD lateralization was also not significant across the training sessions. The present results indicate that BCI training could induce a change of behavioral performance and electrophysiological properties quickly, within just a few hours of training, distributed into three sessions. Multiple training sessions might especially be beneficial for the low BCI performers.

17.
Cognition ; 182: 14-24, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30212652

RESUMO

What is the relationship between bilingual language control (BLC) mechanisms and domain-general executive control (EC) processes? Do these two domains share some of their mechanisms? Here, we take a novel approach to this question, investigating whether short-term language switching training improves non-linguistic task switching performance. Two groups of bilinguals were assigned to two different protocols; one group was trained in language switching (switching-task training group) another group was trained in blocked language picture naming (single-block training group). Both groups performed a non-linguistic and linguistic switching task before (pre-training) and after training (post-training). Non-linguistic and linguistic switch costs decreased to a greater extent for the switching-task training than for the single-block training group from pre- to post-training. In contrast, mixing costs showed similar reductions for both groups. This suggests short-term language switching training can transfer to the non-linguistic domain for certain sub-mechanisms (i.e., switch cost). Thus, there is some overlap of the control mechanisms across domains.


Assuntos
Função Executiva/fisiologia , Multilinguismo , Prática Psicológica , Desempenho Psicomotor/fisiologia , Transferência de Experiência/fisiologia , Adulto , Feminino , Humanos , Masculino , Atividade Motora/fisiologia , Psicolinguística , Percepção Visual/fisiologia , Adulto Jovem
18.
Front Psychol ; 9: 1976, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30410454

RESUMO

Motor imagery is often used inducing changes in electroencephalographic (EEG) signals for imagery-based brain-computer interfacing (BCI). A BCI is a device translating brain signals into control signals providing severely motor-impaired persons with an additional, non-muscular channel for communication and control. In the last years, there is increasing interest using BCIs also for healthy people in terms of enhancement or gaming. Most studies focusing on improving signal processing feature extraction and classification methods, but the performance of a BCI can also be improved by optimizing the user's control strategies, e.g., using more vivid and engaging mental tasks for control. We used multichannel EEG to investigate neural correlates of a sports imagery task (playing tennis) compared to a simple motor imagery task (squeezing a ball). To enhance the vividness of both tasks participants performed a short physical exercise between two imagery sessions. EEG was recorded from 60 closely spaced electrodes placed over frontal, central, and parietal areas of 30 healthy volunteers divided in two groups. Whereas Group 1 (EG) performed a physical exercise between the two imagery sessions, Group 2 (CG) watched a landscape movie without physical activity. Spatiotemporal event-related desynchronization (ERD) and event-related synchronization (ERS) patterns during motor imagery (MI) tasks were evaluated. The results of the EG showed significant stronger ERD patterns in the alpha frequency band (8-13 Hz) during MI of tennis after training. Our results are in evidence with previous findings that MI in combination with motor execution has beneficial effects. We conclude that sports MI combined with an interactive game environment could be a future promising task in motor learning and rehabilitation improving motor functions in late therapy processes or support neuroplasticity.

19.
Front Physiol ; 9: 1013, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30131705

RESUMO

Skeletal muscle generates force by either shortening (concentrically) or lengthening (eccentrically). Eccentric (ECC) exercise is characterized by a lower metabolic demand and requires less muscle activity than concentric (CON) exercise at the same level of exerted force. However, the specific effect of ECC training vs. CON training on lean and fat mass remains underexplored. The first aim of this paper was to review the available evidence regarding the effects of ECC training on whole body and segmental lean and fat mass and, when possible, compare these with the effects of CON training. The second aim was to provide some insights into the main mechanical, physiological, and metabolic adaptations of ECC training that contribute to its effects on body composition. The third aim was to determine the beneficial effects of ECC exercise on health-related parameters in overweight and obese patients. ECC training is an effective modality to improve lean mass, but when matched for load or work, the difference between ECC and CON trainings seems unclear. A few studies reported that ECC training is also efficient at reducing fat mass. By increasing post-exercise resting energy expenditure, modifying metabolic substrate, and improving both blood lipid profile and insulin resistance, ECC training is a potential exercise modality for individuals with chronic conditions such as those who are overweight and obese. Further investigations using standardized experimental conditions, examining not only segmental but also whole body composition, are required to compare ECC and CON trainings.

20.
Heart Fail Clin ; 14(3): 425-430, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29966639

RESUMO

Within the last years, exercise training and rehabilitation as add-on to medical treatment has become an emerging field in pulmonary hypertension. Owing to the beneficial effects of exercise training in pulmonary hypertension, the new European Respiratory Society/European Society of Cardiology guidelines for pulmonary hypertension recommended a supervised and closely monitored exercise and respiratory training/rehabilitation as add-on to medical therapy (class IIa, level of evidence B). In this article, different training modalities, effects of exercise training, possible pathobiological mechanisms of action, and future research questions are discussed.


Assuntos
Terapia por Exercício/métodos , Hipertensão Pulmonar/reabilitação , Tolerância ao Exercício/fisiologia , Humanos , Hipertensão Pulmonar/fisiopatologia , Qualidade de Vida , Taxa de Sobrevida
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