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1.
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.

2.
Biol Sport ; 40(2): 345-352, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37077792

RESUMO

This study aimed to identify the most important variables of male and female beach handball workload demands and compare them by sex. A total of 92 elite Brazilian beach handball players (54 male: age 22.1 ± 2.6 years, height 1.8 ± 0.5 m, weight 77.6 ± 13.4 kg; and 38 female: age 24.4 ± 5.5 years, height 1.7 ± 0.5 m, weight 67.5 ± 6.5 kg) were analyzed in 24 official matches during a four-day congested tournament. From 250 variables measured by the inertial measurement unit, fourteen were extracted for analysis using Principal Component Analysis as selection criteria. Five Principal Components (PC) were extracted that explained 81.2-82.8% of total variance (overview of workload demands during beach handball). Specifically, 36.2-39.3% was explained by PC1 (DistanceExpl, Distance, Distance4-7 km/h, and Acc), 15-18% by PC2 (AccMax, Acc3-4 m/s, Dec4-3 m/s), 10.7-12.9% by PC3 (JumpsAvg Take-Off, JumpsAvg Landing and PLRT), 8-9.4% by PC4 (Distance> 18.1 km/h, SpeedMax), and 6.7-7.7% by PC5 (HRAvg and Step Balance). Sex-related differences were found in the PC distribution of variables, as well as in selected variables (HRAvg, Dec4-3 m/s, Acc3-4 m/s, JumpsAvg Take-Off, JumpsAvg Landing, AccMax, Distance, Distance4-7 km/h, Acc, SpeedMax) with higher values in male players (p < .05). In conclusion, the sex-related PC distribution and workload demands in beach handball should consider for training design and injury prevention programs.

3.
J Strength Cond Res ; 37(10): 2058-2063, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37015015

RESUMO

ABSTRACT: Loturco, I, Grazioli, R, Veeck, F, Nakamura, FY, Inácio, M, Schons, P, Preissler, A, Pinto, RS, Pereira, LA, McGuigan, MR, and Cadore, EL. Effects of a short-term detraining period on the strength deficit and functional performance of highly trained soccer players. J Strength Cond Res 37(10): 2058-2063, 2023-The aim of this study was to examine the effects of a 4-week detraining period on the neuromuscular performance of highly trained soccer players. Pre and post detraining, 18 adult soccer players (age: 27 ± 4.9 years; height: 180.2 ± 7.1 cm; body mass [BM]: 78.9 ± 7.6 kg) performed vertical jumps, 20-m linear sprints, curve sprint and change of direction speed tests, and a progressive loading test in the half-squat exercise with loads corresponding to 50, 100, and 150% of the players' BM to assess the peak-force (PF), mean power (MP), and strength-deficit (SDef). Pre and post differences in the variables of interest were analyzed using paired t -tests and effect sizes (ES). No significant changes were detected for vertical jumping height and sprint times. Higher PF at 50 and 100% BM and lower SDef were shown when comparing pre- and postassessments (ES = 0.66, 0.68, 0.55; p = 0.018, 0.016, and 0.046, respectively). The MP at 50 and 100% BM increased significantly after the detraining phase (ES = 0.56, 0.82; p = 0.049 and 0.007, respectively). The results indicate that these athletes were able to maintain and achieve satisfactory levels of performance after a short period of training cessation. Interestingly, some strength- and power-derived parameters improved significantly after short-term detraining, which may have important implications for training programs aimed at maximizing speed and power performance. It is recommended that coaches test their players not only at the beginning but also at the end of the season, to better evaluate variations in performance and thus create more efficient and tailored training strategies.


Assuntos
Desempenho Atlético , Corrida , Futebol , Adulto , Humanos , Adulto Jovem , Exercício Físico , Desempenho Físico Funcional , Força Muscular
4.
Biol Sport ; 39(4): 1043-1048, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36247935

RESUMO

The aims of this study were to: 1) provide and compare the height achieved during Smith machine (SM) and free weight (FW) loaded jumps executed over a wide spectrum of loads (40-120% of body mass [BM]); and 2) test the difference between loaded and unloaded squat jump (SJ) and countermovement jump (CMJ) attempts in ten highly trained male sprinters. On the first visit, athletes performed unloaded SJ and CMJ, loaded SJ with loads corresponding to 40, 60, 80, 100, and 120% BM, and loaded CMJ at 100% BM using an Olympic barbell (FW). On the second visit, they performed loaded SJ and CMJ tests under the same loading conditions on the SM device and, subsequently, a half-squat one-repetition maximum (1RM) assessment. The relative strength (RS = 1RM/BM) of the athletes was 2.54 ± 0.15. Loaded SJ performance was similar between SM and FW, and across all loading conditions. Differences in favour of CMJ (higher jump heights compared with SJ) were superior in the unloaded condition but decreased progressively as a function of loading. In summary, sprinters achieved similar SJ heights across a comprehensive range of loads, regardless of the execution mode (FW or SM). The positive effect of the countermovement on jump performance is progressively reduced with increasing load.

5.
J Strength Cond Res ; 36(6): 1708-1714, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35622114

RESUMO

ABSTRACT: Nakamura, FY, Torres, VBC, da Silva, LS, Gantois, P, Andrade, AD, Ribeiro, ALB, Brasileiro-Santos, MdS, and Batista, GR. Monitoring heart rate variability and perceived well-being in Brazilian elite beach volleyball players: A single-tournament pilot study. J Strength Cond Res 36(6): 1708-1714, 2022-The aim of this study was to monitor the changes in heart rate variability (HRV) and perceptual well-being status after a beach volleyball (BV) tournament day in high-level U17 and senior players. Seventeen BV players (U17 [15-16 years]: n = 08; and senior [19-41 years]: n = 09) competing at national and/or international BV level participated in this study. Resting HRV and perceptual well-being measures were recorded across 4 moments: night 1 (prematches night), morning 1 (prematches morning), night 2 (postmatches night), and morning 2 (postmatches morning). Session rating of perceived exertion was assessed 10 minutes after each match, and accumulated match loads were used for analysis. Senior players presented higher values of natural logarithm of square root of the mean squared differences of successive RR intervals (lnRMSSD) at the 4 observation moments than U17 players (p = 0.006). Within-subjects analysis showed a larger mean difference regarding both lnRMSSD and natural logarithm SD of normal R-R intervals (lnSDNN) between night 1 vs. night 2 in U17 players (effect size = 1.11 and, 0.96, respectively) compared with senior (effect size = 0.40 and 0.32, respectively). Accumulated match loads were negatively correlated with percentage change in lnRMSSD (r = -0.54; p = 0.037). U17 players showed higher well-being variation than senior (group × time; p = 0.02). In conclusion, the lnRMSSD index was able to discriminate the U17 and senior BV players, and maintaining high vagally related HRV indices is an important response to BV training and competition.


Assuntos
Futebol , Voleibol , Brasil , Frequência Cardíaca/fisiologia , Humanos , Projetos Piloto , Futebol/fisiologia
6.
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
7.
J Sports Med Phys Fitness ; 62(3): 317-323, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33871236

RESUMO

BACKGROUND: This study aimed to quantify internal training load and changes in vertical jumping ability and endurance capacity of professional volleyball players during the preseason, and to explore relationships between players' physical qualities at the beginning of the preseason with internal training load accumulated during the first two weeks of training. METHODS: Sixteen male professional volleyball players from a team participating in the Brazilian National Super League took part in the study. Before and after a 10-week preseason, their vertical jumping ability and endurance capacity were assessed by squat jump, countermovement jump without and with arm swing, and YoYo endurance test, level 1. The internal training load was quantified by the session rating of perceived exertion method. Results were analyzed using analysis of variance, magnitude-based inference and Pearson's correlation. RESULTS: The internal training load varied between 1388±111 arbitrary units (a.u.) and 3852±149 a.u., and performance in all the tests was positively changed (small to moderate effect sizes) at end of preseason training. Significant (P<0.05) very large and large correlations were observed between squat jump (r=-0.81) and YoYo endurance test (r=-0.64) performances and internal training load accumulated during the first two training weeks, respectively. CONCLUSIONS: The internal training load and training strategies undertaken by the investigated team were effective to improve players' vertical jumping ability and endurance capacity. Coaches need to improve these physical qualities of volleyball players in order to improve their tolerance to training.


Assuntos
Desempenho Atlético , Voleibol , Brasil , Humanos , Masculino , Postura
8.
Percept Mot Skills ; 128(6): 2745-2766, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34404292

RESUMO

We studied the effects of repeated inducements of mental fatigue (MF) from using social media on smartphones immediately before training sessions by young male volleyball athletes, focusing specifically on their decision-making, endurance, and countermovement jump performance (CMJ). We pair-matched 24 participants according to their decision-making abilities and then, randomly assigned them to one of two 4-week block training groups: control (CON) and smartphone use (SMA). For a 30-minute period before each training session, the CON group watched TV and the SMA group used social media apps on smartphones. We found a significant group x time interaction effect for decision making (attack, p = 0.03; passing, p = 0.02) during training blocks. More specifically, only the CON group improved their decision making (attack, p = 0.03; passing, p = 0.02). Both groups significantly improved their CMJ performance (p = .01), with no significant group x time interaction effect for CMJ (p = 0.91). Neither group significantly improved their endurance (p = 0.56). We concluded that 30-minutes of repetitive social media app use on a smartphone immediately before 4-weeks of volleyball training sessions negatively affected decision-making in young male volleyball athletes.


Assuntos
Desempenho Atlético , Mídias Sociais , Voleibol , Humanos , Masculino , Fadiga Mental , Fadiga Muscular , Força Muscular
9.
J Funct Morphol Kinesiol ; 6(1)2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33809818

RESUMO

BACKGROUND: The association between heart rate variability (HRV), training load (TL), and performance is poorly understood. METHODS: A middle-aged recreational female runner was monitored during a competitive 20-wk macrocycle divided into first (M1) and second mesocycle (M2) in which best performances over 10 km and 21 km were recorded. Volume (km), session rating of perceived exertion (sRPE), TL, and monotony (mean TL/SD TL) were the workload parameters recorded. The root mean square of the successive differences in R-R intervals (RMSSD), its coefficient of variation (RMSSDcv), and the RMSSD:RR ratio were the HRV parameters monitored. RESULTS: During M2, RMSSD (p = 0.006) and RMSSD:RR (p = 0.002) were significantly increased, while RR was significantly reduced (p = 0.017). Significant correlations were identified between monotony and volume (r = 0.552; p = 0.012), RR (r = 0.447; p = 0.048), and RMSSD:RR (r = -0.458; p = 0.042). A sudden reduction in RMSSD (from 40.31 to 24.34 ms) was observed the day before the first symptoms of an influenza. CONCLUSIONS: The current results confirm the practicality of concurrent HRV and sRPE monitoring in recreational runners, with the RMSSD:RR ratio indicative of specific adaptations. Excessive training volume may be associated to both elevated monotony and reduced RMSSD:RR. Identification of mesocycle patterns is recommended for better individualization of the periodization used.

10.
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
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