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1.
Int J Sport Nutr Exerc Metab ; 34(1): 30-37, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37898479

RESUMO

Guarana (GUA) seed extract, containing caffeine (CAF) and additional bioactive compounds, may positively affect mental performance, but evidence regarding exercise is limited. This investigation assessed acute GUA ingestion compared with CAF on endurance performance. Eleven endurance-trained noncyclists and cyclists (V˙O2peak = 49.7 ± 5.9, 60.4 ± 4.6 ml·kg·min-1) completed a double-blind, crossover experiment after ingesting (a) 100 mg CAF, (b) 500 mg GUA (containing 130 mg CAF), or (c) placebo (P) prior to 60-min fixed cycling workload (FIX) + 15-min time trial. Oxygen uptake, heart rate, respiratory exchange ratio, blood glucose, and lactate were not different (p ≥ .052) during FIX. A significant interaction (p = .042) for perceived exertion was observed at 50-min FIX with lower rating (p = .023) for GUA versus CAF but not compared with P. Work accumulated over 15-min time trial was greater (p = .038) for GUA versus P due to higher early (1-11 min) work outputs. Work performance favored (effect size = 0.18; 95% confidence interval [0.003, 0.355], p = .046) GUA (241.4 ± 39.9 kJ) versus P (232.1 ± 46.6 kJ), but CAF (232.3 ± 43.9) was not different from GUA (effect size = 0.19; 95% confidence interval [-0.022, 0.410], p = .079) or P. Postexercise strength loss was not attenuated with GUA (-5.6 ± 8.5%) or CAF (-8.3 ± 9.4%) versus P (-10.3 ± 5.1%). Acute GUA ingestion improved work performance relative to P, but effects were trivial to small and unrelated to altered substrate oxidation or muscular strength. Ergogenicity may involve central mechanisms reducing perceived effort with GUA (containing 130 mg caffeine). Due to issues related to identical matching of dosage, whether GUA confers additional benefits beyond its CAF content cannot be determined at present.


Assuntos
Desempenho Atlético , Paullinia , Humanos , Cafeína , Resistência Física/fisiologia , Ácido Láctico , Exercício Físico/fisiologia , Método Duplo-Cego , Estudos Cross-Over , Desempenho Atlético/fisiologia
2.
Int J Exerc Sci ; 16(6): 638-653, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37621711

RESUMO

This study aims to elucidate the internal load, performance, physiological, and perceptual recovery responses during four weeks of traditional judo training. Ten cadet and junior judo athletes were evaluated daily for four weeks, in which their perception of recovery, heart rate variability, handgrip strength, and countermovement jump performance were assessed. A one-way repeated-measures ANOVA was performed to analyze the variables across the weeks. A significant time effect in internal load (F = 6.51; p = 0.001) has been observed. Handgrip test performance showed significantly higher values in the 3rd and 4th weeks (p <0.001), while countermovement jump performance was significantly higher in the 4th week (p =0.0007). The heart rate variability's coefficient of variation was lower in both the 3rd and 4th weeks (p =0.02). Regarding perceptual aspects, the Hooper Index showed a significant time effect (p =0.04), but pairwise comparison did not reveal differences between weeks. The present study indicates that neuromuscular, physiological, and perceptual responses to training load alterations present different time courses. This must be considered for the adequate monitoring of training programs.

3.
Int J Exerc Sci ; 15(4): 771-782, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992500

RESUMO

This study aimed to compare the effects of high-speed resistance training (HSRT) and low-speed resistance training (LSRT) in physical fitness, and functional performance in untrained older women. Twenty-four women (62.2 ± 2.7 years old) were allocated to the HSRT or LSRT groups. The HSRT and LSRT groups underwent a similar training program [3 sets of 8 to 12 repetitions at 90% of 10 maximum repetitions] for 14 weeks, twice a week. The LSRT group performed the exercises with 3 seconds in the concentric and eccentric phases, while the HSRT group performed with the concentric phase as quickly as possible and 3 seconds in the eccentric phase. Participants completed pre-and post-training testing to assess strength, flexibility, muscle endurance, power, walking speed, functional balance, and aerobic endurance. Two-way mixed-model ANOVA with repeated measures was applied for each variable, and the Bonferroni post hoc was used when necessary. Statistical significance was set at p < 0.05. No significant group*time interactions were found for any variable. Time main-effect suggested significant improvements for the 10 RM bench press (F = 46.1; p < 0.001), 10 RM leg press (F = 49.8; p < 0.001), sit-to-stand test (F = 10.4; p = 0.004), sit and reach (F = 10.5; p = 0.004), Timed Up-and-Go (F = 29.8; p < 0.001) and 6-min walking test (F = 41.6; p < 0.001). Thus, the configurations of RT tested here were similarly efficient to improve the functional performance of untrained older women. In addition, both groups showed significant gains in muscle strength, but not in muscle power and gait speed.

4.
J Sport Exerc Psychol ; 44(4): 272-285, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35613846

RESUMO

The objective of this study was to analyze the effect of anodal transcranial direct current stimulation (a-tDCS) over the motion-sensitive midtemporal area on perceptual-cognitive skills (visuomotor and basketball decision-making skills) in mentally fatigued basketball players. A total of 20 male basketball players were recruited. This was a randomized, double-blinded, and counterbalanced crossover study with two experimental conditions: a-tDCS and Sham. The participants completed the basketball decision-making task and visuomotor skill after performing a 60-min sport-based videogame task with anodal (i.e., a-tDCS) or placebo (Sham) stimulation over the motion-sensitive middle temporal area. Worse response time was observed in visuomotor skill for Sham than a-tDCS postexperiment (p < .05). There was no main condition effect for accuracy of visuomotor skill (p > .05). There was more impairment in accuracy and response time in basketball decision-making skills for the Sham condition than a-tDCS (p < .05). Notably, a-tDCS over the motion-sensitive middle temporal area removed the negative effects of mental fatigue on perceptual-cognitive skills.


Assuntos
Basquetebol , Córtex Motor , Estimulação Transcraniana por Corrente Contínua , Cognição/fisiologia , Estudos Cross-Over , Humanos , Masculino , Fadiga Mental , Córtex Motor/fisiologia
5.
J Strength Cond Res ; 36(2): 461-468, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31855926

RESUMO

ABSTRACT: Campos, BT, Penna, EM, Rodrigues, JGS, Mendes, TT, Maia-Lima, A, Nakamura, FY, Vieira, ÉLM, Wanner, SP, and Prado, LS. Influence of mental fatigue on physical performance, and physiological and perceptual responses of judokas submitted to the Special Judo Fitness Test. J Strength Cond Res 36(2): 461-468, 2022-Mentally fatigued athletes present impaired aerobic performance, strength endurance, and manual dexterity, despite no changes in anaerobic performance and maximal muscle strength and power. Noteworthy, the effect of mental fatigue on physical performance during high-intensity intermittent tests that require specific motor skills of fighting sports has not been investigated. Therefore, this study aimed to verify whether mental fatigue influences performance and physiological and perceptual responses of judokas subjected to a high-intensity intermittent test designed specifically and validated for judo. Each judoka performed 2 experimental trials-a control trial one and the other one after the induction of mental fatigue. These trials were scheduled in a random and balanced order. In both trials, lactate, glucose, and cortisol concentrations, the heart rate variability, and perceptual variables were collected after the initial treatment and after the Special Judo Fitness Test (SJFT). The initial treatment consisted of a 30-minute cognitive demanding task (Stroop Color test) or watching a movie (control) and was followed by the SJFT. The Stroop Color test increased the perceptions of mental fatigue and effort, without affecting motivation for subsequent testing. Unexpectedly, mentally fatigued athletes did not show reduced performance during the SJFT. Regarding the physiological variables, no significant differences were identified between the 2 experimental conditions. We conclude that physical performance measured during a specific test for judokas is not impaired by a previous 30-minute cognitive task that causes mental fatigue. In addition, this cognitive task did not influence the physiological changes induced by the specific physical test.


Assuntos
Desempenho Atlético , Artes Marciais , Teste de Esforço , Humanos , Fadiga Mental , Aptidão Física , Desempenho Físico Funcional
6.
Int J Sports Physiol Perform ; 16(4): 557-564, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33440337

RESUMO

PURPOSE: To compare the posttraining recovery timeline of elite Brazilian futsal athletes before (Pre-PS) and after 10 weeks of the preseason (Post-PS) period of high-intensity technical-tactical training. METHODS: At the start (n = 13) and at the end of the preseason (n = 7), under-20 male futsal players undertook fitness testing for maximal aerobic power, the countermovement jump (CMJ), and the 10-m sprint with change of direction. Furthermore, at both Pre-PS and Post-PS, the players participated in a training session where performance and psychophysiological measures were recorded before, immediately, 3, 24, and 48 hours postsession. The measures included CMJ, 10-m sprint, creatine kinase, Total Quality Recovery Scale, and Brunel Mood Scale. Effect size (ES) analyses compared fitness and posttraining recovery values for each parameter at Pre-PS versus Post-PS. RESULTS: Only trivial ES (-0.02 to 0.11) was evident in maximal aerobic power, CMJ, and 10-m sprint at Post-PS compared with Pre-PS. For the timeline of recovery, only trivial and small ESs were evident for the 10-m sprint (-0.12 to 0.49), though CMJ recovery was improved at 3 hours (0.87) and 48 hours (1.27) at Post-PS and creatine kinase was lower at 48 hours (-1.33) at Post-PS. Perception of recovery was improved in Post-PS at 3 hours (1.50) and 24 hours postsession (0.92). Furthermore, perception of effort was lower immediately after the session (-0.29), fatigue was lower at 3 hours (-0.63), and vigor responses were improved in all postseason assessments (0.59 to 1.13). CONCLUSION: Despite minimal changes in fitness, preseason training attenuated players' perception of effort and fatigue and improved their recovery profile following a high-intensity technical-tactical training session.


Assuntos
Desempenho Atlético , Futebol , Brasil , Fadiga , Humanos , Masculino , Percepção
7.
J Strength Cond Res ; 35(8): 2302-2308, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31009426

RESUMO

ABSTRACT: Ramos, GP, Nakamura, FY, Penna, EM, Mendes, TT, Mahseredjian, F, Lima, AM, Garcia, ES, Prado, LS, and Coimbra, CC. Comparison of physical fitness and anthropometrical profiles among Brazilian female soccer national teams from U15 to senior categories. J Strength Cond Res 35(8): 2302-2308, 2021-This study aimed to compare anthropometric and physical fitness of Brazilian female national team soccer players from the U15 to senior categories, and to compare the physical performance between selected and nonselected players. Subjects included 231 athletes (U15, n = 46, U17, n = 49, U20, n = 98, and Senior, n = 38). Body mass, height, sum of skinfolds, squat jump (SJ), countermovement jump (CMJ), 20-m linear sprint, and Yo-Yo IR1 were assessed. The U15 players were shorter than all other groups (p < 0.01) and lighter than U20 players (p < 0.01). Regarding physical tests, Senior athletes presented higher SJ compared with U20, and both showed higher CMJ and SJ compared with the U15 and U17 (p < 0.05). Senior athletes were also faster than players of all other categories in 20-m sprint (p < 0.01) and covered the greatest distance in the Yo-Yo IR1 (p < 0.05). U20 were better in the Yo-Yo IR1 than the younger groups (p < 0.05). When comparing selected and nonselected players, no differences were identified in anthropometric measures (p > 0.05). However, selected players from U17, U20, and Senior teams showed better performance in Yo-Yo IR1 than nonselected ones (p < 0.05). Finally, selected senior athletes also presented higher CMJ and SJ than nonselected players (p < 0.05). These results suggest that, although there is a tendency for maintenance in anthropometric measures from the age of 15 years, there are substantial improvements in speed, lower-body power, and aerobic capacity from U20 age group. In addition, it seems that intermittent aerobic fitness contributes to the selection of players to international tournaments in national teams.


Assuntos
Desempenho Atlético , Futebol , Adolescente , Antropometria , Atletas , Feminino , Humanos , Aptidão Física
8.
J Hum Kinet ; 72: 265-278, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32269667

RESUMO

We aimed to create a single subjective method to assess both internal training loads and subsequent fatigue. This new training-fatigue (dose-response) scale (TFS) was composed of two similar scales with the same properties, metrics and construction criteria. These two scales were designed to rate the perceived exertion (RPETFS) and perceived fatigue (RPFTFS) in professional soccer players. Twenty-two athletes participated to establish reliability, and 15 participated to establish validity. For reliability, the intraclass correlation coefficient (ICC) and standard error of measurement (SEM) were used. For criterion validity, the Spearman's correlation coefficient and linear regression analyses were applied. Associations between RPETFS and RPFTFS were verified by a chi square test, and a further factorial exploratory analysis was conducted. RPETFS and RPFTFS were found to be reliable (ICC 0.74 and 0.77, SEM 0.30 and 0.30, respectively) and valid. RPETFS was best explained by the internal load of the Banister training impulse (p < 0.001), while RPFTFS was best explained by the internal load of the Stagno training impulse (p < 0.001). An association was found between the scales (RPETFS and RPFTFS) in which training duration had a more substantial impact on these subjective perceptions than did training intensity (p < 0.01). RPETFS and RPFTFS scales are reliable and valid for monitoring training sessions in Brazilian professional soccer players. The simultaneous oscillations of the RPETFS and RPFTFS scores can be used by staff members to better plan weekly training programs based on dose-response ratings. Finally, training duration must be carefully controlled because it has a greater impact than intensity on subjective perceptions.

9.
Int J Sports Physiol Perform ; 15(5): 648-653, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31896076

RESUMO

PURPOSE: To determine whether daily perceived recovery is explained from a multifactorial single-session classification of recovery (ie, faster vs slower) or other circumstantial factors (ie, previous training load, self-reported sleep, or phase of the microcycle). METHODS: Nineteen elite male futsal players were initially allocated to a recovery-classification group (faster recovery, slower physiological, or slower perceptual) based on previous research using a multifactorial cluster-analysis technique. During 4 ensuing weeks of preseason, training loads were monitored via player load, training impulse, and session rating of perceived exertion. Before each day's training, players reported their perception of recovery (Total Quality of Recovery scale [TQR]) and the number of hours and perceived quality of sleep the night prior. A hierarchical linear mixed model was used to analyze the effect of the different recovery profiles, training load, sleep, and phase of the microcycle (ie, start, middle, end) on daily TQR. RESULTS: The recovery classification of players (P = .20), training load (training impulse, P = .32; player load, P = .23; session rating of perceived exertion, P = .46), and self-reported hours slept the night before (P = .45) did not significantly influence TQR. However, perceived sleep quality (P < .01) and phase of the microcycle (P < .01) were significantly associated with TQR (r2 = .41). CONCLUSIONS: Neither recovery classification nor prior training load influenced perceived recovery during the preseason. However, higher TQR was evident with better self-reported sleep quality, whereas lower values were associated with phases of the training week.


Assuntos
Percepção/fisiologia , Condicionamento Físico Humano/fisiologia , Esforço Físico/fisiologia , Autorrelato , Sono/fisiologia , Futebol/fisiologia , Humanos , Adulto Jovem
10.
Motriz (Online) ; 26(2): e10200203, 2020. graf
Artigo em Inglês | LILACS | ID: biblio-1135307

RESUMO

Abstract Aim: To compare two different randori structure (high volume and short pauses - TRAD training vs low volume with long pauses - COMP training) in the neuromuscular and metabolic responses of elite judo athletes. Methods: The first situation (TRAD) consisted of 12 randoris of 5 minutes with 45 seconds rest, and the other situation (COMP), consisted of 6 randoris of 5 minutes with 10 minutes between them. Physiological (Blood Lactate and Creatine Kinase), neuromuscular (Countermovement Jump and Medicine Ball Throws) and perceptive variables (Rating Perceived Exertion) were measured before and at the end of the sessions. Results: The subjective perception of effort at the end of the training was significantly higher in the TRAD training type (TRADpost: 8.1 ± 0.9 AU; COMPpost: 6.6 ± 1.5 AU, p <0.001). Blood lactate concentration (TRADpost: 6.4 ± 2.2 mmol/L; COMPpost: 8.1 ± 2.9 mmol/L; p <0.001), CMJ height (TRADpost: 36.2 ± 4.6 cm; COMPpost: 35.9 ± 4.3 cm, p = 0.012) and upper limb power performance (TRADpost: 6.4 ± 0.9 m; COMPpost: 6.3 ± 0.9 m p = 0.03) were significantly higher at the end of the two training sessions compared to their start, but there are no group effect. There is group effect in CK (TRADpost: 490.7 ± 273.5 U/L; COMPpost: 357.4 ± 203.8 U/L; p <0.001). Conclusions: This study demonstrated that TRAD and COMP Judo training induced similar physical demands, and both seem to not be enough to reach higher intensities, which made them distant methods of competitive reality.


Assuntos
Humanos , Exercício Físico/fisiologia , Artes Marciais/fisiologia , Fadiga Muscular/fisiologia , Manifestações Neuromusculares , Atletas
11.
J Strength Cond Res ; 33(12): 3414-3422, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28767483

RESUMO

Ramos, GP, Nakamura, FY, Penna, EM, Wilke, CF, Pereira, LA, Loturco, I, Capelli, L, Mahseredjian, F, Silami-Garcia, E, and Coimbra, CC. Activity profiles in U17, U20, and senior women's Brazilian national soccer teams during international competitions: are there meaningful differences? J Strength Cond Res 33(12): 3414-3422, 2019-The aim of this study was to compare locomotor activity profiles of Brazilian top-class female soccer players competing at distinct age brackets (under 17 [U17], under [U20], and senior). External match load of 14 U17, 14 U20, and 17 senior female soccer players competing in 6-7 full official international matches were assessed using global positioning systems. Total distance covered, distance covered in high intensity (15.6-20 km·h), distance covered in sprints (sprint: >20 km·h), number of accelerations (Acc) >1 m·s, decelerations (Dec) >-1 m·s, and Player Load generally increased across the age brackets (U17

Assuntos
Esforço Físico/fisiologia , Corrida/fisiologia , Futebol/fisiologia , Aceleração , Adolescente , Adulto , Brasil , Desaceleração , Feminino , Sistemas de Informação Geográfica , Humanos , Adulto Jovem
12.
J Hum Kinet ; 64: 99-109, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30429903

RESUMO

Judo is a high-intensity intermittent combat sport which causes cardiac adaptations both morphologically and related to the autonomic nervous system (ANS). Therefore, this study aims to verify the correlation between heart rate variability (HRV) at rest with performance in the Special Judo Fitness Test (SJFT) and whether groups with different RR values at rest show different performance in the SJFT and during post-test recovery. Sixteen judo athletes with 7.2 ± 3.9 years of training experience participated in the study. Before and after the SJFT execution HRV and lactate measurements were conducted. For HRV analysis, we used the mean interval RR, the standard deviation of the RR interval (SDNN), the root mean square of successive differences in RR intervals (RMSSD), the low frequency (LF) and high frequency (HF) in normalized and absolute units. The sample was split into two groups (low RR and high RR) to verify if this variable could differentiate between specific performance. For the SDNN, a significant and moderate correlation (r = 0.53) was found with the total number of throws and throws in the series A (r = 0.56) and B (r = 0.54) and for the RMSSD a correlation with throws during series B (r = 0.59) in the SJFT. However, the groups did not differ in performance and recovery. Therefore, HRV is related to intermittent judo performance; however, it cannot differentiate between judokas at different levels of performance.

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