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1.
Braz. J. Psychiatry (São Paulo, 1999, Impr.) ; 41(4): 324-335, July-Aug. 2019. tab, graf
Artigo em Inglês | LILACS-Express | ID: biblio-1011506

RESUMO

Objective: To present the essential guidelines for pharmacological management of patients with psychomotor agitation in Brazil. Methods: This is a systematic review of articles retrieved from the MEDLINE (PubMed), Cochrane Database of Systematic Reviews, and SciELO databases published from 1997 to 2017. Other relevant articles in the literature were also used to develop these guidelines. The search strategy used structured questions formulated using the PICO model, as recommended by the Guidelines Project of the Brazilian Medical Association. Recommendations were summarized according to their level of evidence, which was determined using the Oxford Centre for Evidence-based Medicine system and critical appraisal tools. Results: Of 5,362 articles retrieved, 1,731 abstracts were selected for further reading. The final sample included 74 articles that met all inclusion criteria. The evidence shows that pharmacologic treatment is indicated only after non-pharmacologic approaches have failed. The cause of the agitation, side effects of the medications, and contraindications must guide the medication choice. The oral route should be preferred for drug administration; IV administration must be avoided. All subjects must be monitored before and after medication administration. Conclusion: If non-pharmacological strategies fail, medications are needed to control agitation and violent behavior. Once medicated, the patient should be monitored until a tranquil state is possible without excessive sedation. Systematic review registry number: CRD42017054440.

2.
J Sports Sci ; : 1-7, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31389308

RESUMO

This study aimed to examine the effects of two jump squat (JS) training programs involving different loading ranges in under-20 soccer players during a preseason period. Twenty-three elite young soccer players performed sprint speed (at 5-, 10-, and 20-m), change-of-direction (COD) speed, JS peak-power (PP), and countermovement jump (CMJ) tests pre and post four weeks of training. Athletes were pair-matched in two groups according to their optimum power loads (OPL) as follows: lower than OPL (LOPL; athletes who trained at a load 20% lower than the OPL) and higher than OPL (HOPL; athletes who trained at a load 20% higher than the OPL). Magnitude-based inferences were used to compare pre- and post-training measures. Meaningful increases in the PP JS were observed for both groups. Likely and possible improvements were observed in the 5- and 10-m sprint velocity in the LOPL group. Meanwhile, possible and likely improvements were observed in the CMJ, 5- and 10-m sprint velocity, and COD speed in the HOPL group. Overall, both training schemes induced positive changes in athletic performance. Soccer coaches and sport scientists can implement the JS OPL-based training schemes presented here, either separately or combined, to improve the physical performance of youth soccer players.

3.
J Sports Sci ; : 1-8, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31354103

RESUMO

The aims of the present study were to provide an in-depth comparison of inter-limb asymmetry and determine how consistently asymmetry favours the same limb during different vertical jump tests. Eighteen elite female under-17 soccer players conducted unilateral squat jumps (SJ), countermovement jumps (CMJ) and drop jumps (DJ) on a portable force platform, with jump height, peak force, concentric impulse and peak power as common metrics across tests. For the magnitude of asymmetry, concentric impulse was significantly greater during the SJ test compared to CMJ (p = 0.019) and DJ (p = 0.003). No other significant differences in magnitude were present. For the direction of asymmetry, Kappa coefficients revealed fair to substantial levels of agreement between the SJ and CMJ (Kappa = 0.35 to 0.61) tests, but only slight to fair levels of agreement between the SJ and DJ (Kappa = -0.26 to 0.18) and CMJ and DJ (Kappa = -0.13 to 0.26) tests. These results highlight that the mean asymmetry value may be a poor indicator of true variability of between-limb differences in healthy athletes. The direction of asymmetry may provide a useful monitoring tool for practitioners in healthy athletes, when no obvious between-limb deficit exists.

4.
J Strength Cond Res ; 2019 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-31136547

RESUMO

Freitas, TT, Alcaraz, PE, Calleja-González, J, Arruda, AFS, Guerriero, A, Kobal, R, Reis, VP, Pereira, LA, and Loturco, I. Differences in change of direction speed and deficit between male and female national rugby sevens players. J Strength Cond Res XX(X): 000-000, 2019-The aims of this study were to assess the change of direction (COD) deficit in different tasks and to investigate the differences in COD ability and COD deficit between male and female rugby sevens players. Thirty-six elite rugby players from the Brazilian National senior sevens teams (18 males and 18 females) completed the following physical assessments: squat and countermovement jumps; drop jump from a 45-cm height; horizontal single and triple jumps; 40-m linear sprint; Pro-agility, L-drill, and Zig-zag COD tests; and 1 repetition maximum test in the squat exercise. The differences between male and female performances were determined using magnitude-based inferences, an independent t test, and effect sizes (ES). Pearson's product-moment correlations were performed to determine the relationships among the different COD velocities and COD deficits. Men demonstrated likely to almost certainly significantly higher performances than women in all speed-power assessments and COD tasks (ES ranging from 0.61 to 2.09; p < 0.05), with the exception of the Zig-zag drill (ES = 0.24; p > 0.05). Furthermore, males displayed significantly greater COD deficits in all tests and higher sprint momentum (ES ranging from 0.78 to 2.95; p < 0.05). Large significant relationships among COD velocities (r ranging from 0.71 to 0.88; p < 0.05) and almost perfect significant correlations among all COD deficits (r ranging from 0.90 to 0.95; p < 0.05) were obtained in both sexes. The present results indicate that male rugby players are less efficient at changing direction, relative to their maximum sprint velocity. In addition, the correlations between the different COD deficits and COD speeds suggest that elite rugby players demonstrate similar ability to change direction, independently of the angle of directional change. From a practical perspective, this implies that a more comprehensive training strategy including eccentric exercises, acceleration-deceleration drills, and directional change technique is warranted to improve the COD ability (and reduce the COD deficit) of faster and more powerful rugby sevens players.

5.
Res Q Exerc Sport ; 90(3): 355-361, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31082316

RESUMO

Purpose: This study examined the relationships between the Yo-Yo Intermittent Recovery Test level 1 (Yo-Yo IR1) and resting heart rate variability (HRV) and submaximal 5'-5' test derived measures in novice male soccer players. Methods: Forty players (11.54 ± 0.58 years) from a soccer academy participated in this study, performing physical tests on two different days, separated by 48 h, as follows: (day 1) resting HRV and Yo-Yo IR1 test, and (day 2) anthropometric assessments (for peak height velocity assessment [PHV]) and the 5'-5' test. The Pearson product-moment correlation coefficient was used to determine the correlations between Yo-Yo IR1 performance and the remaining variables. A partial correlation analysis was further performed using age, stature, body mass, distance to PHV, and age at PHV as "confounders." Results: The highest correlation score was observed between Yo-Yo IR1 performance and resting HRV, when the absolute age was used as confounder (r = 0.72; p < .05). Conclusions: We observed that a practical measure of parasympathetic activity at rest is largely associated with performance obtained during a traditional intermittent endurance performance test.

6.
Rev. bras. psiquiatr ; 41(2): 153-167, Mar.-Apr. 2019. tab, graf
Artigo em Inglês | LILACS-Express | ID: biblio-990823

RESUMO

Objective: To present the essential guidelines for non-pharmacological management of patients with psychomotor agitation in Brazil. Methods: These guidelines were developed based on a systematic review of articles published from 1997 to 2017, retrieved from MEDLINE (PubMed), Cochrane Database of Systematic Review, and SciELO. Other relevant articles identified by searching the reference lists of included studies were also used to develop these guidelines. The search strategy used structured questions formulated using the PICO model, as recommended by the Guidelines Project of the Brazilian Medical Association. Recommendations were summarized according to their level of evidence, which was determined using the Oxford Centre for Evidence-based Medicine system and critical appraisal tools. Results: We initially selected 1,731 abstracts among 5,362 articles. The final sample included 104 articles that fulfilled all the inclusion criteria. The management of agitated patients should always start with the least coercive approach. The initial non-pharmacological measures include a verbal strategy and referral of the patient to the appropriate setting, preferably a facility designed for the care of psychiatric patients with controlled noise, lighting, and safety aspects. Verbal de-escalation techniques have been shown to decrease agitation and reduce the potential for associated violence in the emergency setting. The possibility of underlying medical etiologies must be considered first and foremost. Particular attention should be paid to the patient's appearance and behavior, physical signs, and mental state. If agitation is severe, rapid tranquilization with medications is recommended. Finally, if verbal measures fail to contain the patient, physical restraint should be performed as the ultimate measure for patient protection, and always be accompanied by rapid tranquilization. Healthcare teams must be thoroughly trained to use these techniques and overcome difficulties if the verbal approach fails. It is important that healthcare professionals be trained in non-pharmacological management of patients with psychomotor agitation as part of the requirements for a degree and graduate degree. Conclusion: The non-pharmacological management of agitated patients should follow the hierarchy of less invasive to more invasive and coercive measures, starting with referral of the patient to an appropriate environment, management by a trained team, use of verbal techniques, performance of physical and mental assessment, use of medications, and, if unavoidable, use of the mechanical restraint. Systematic review registry number: CRD42017054440.

7.
Int J Sports Physiol Perform ; : 1-25, 2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-30958067

RESUMO

PURPOSE: This study aimed to examine the variations in the velocity of contraction (Vc) assessed via tensiomyography (TMG), vertical jumping ability, and sprinting speed induced by four different exercise protocols (i.e., strength, sprint, plyometric, and technical training sessions) in fourteen male National Team rugby players (age: 21.8 ± 2.6 years; weight: 83.6 ± 8.5 kg; height: 177.4 ± 6.7 cm). METHODS: Physical tests were conducted immediately pre- and post-four distinct workouts, in the following order: (1) TMG in the rectus femoris (RF) and biceps femoris (BF) muscles; (2) squat and countermovement jumps (SJ and CMJ); and (3) 30-m sprint velocity. To analyze the differences in the assessed variables before and after each training session, the differences based on magnitudes were calculated. RESULTS: After strength and plyometric workouts, the players presented possible to almost certain impairments in sprint and jump performance and in the Vc RF (effect sizes varying from 0.26 to 0.64). After the sprint training session, possible to very likely decreases were observed in the SJ, 30-m sprint, and Vc BF (effect sizes varying between 0.21 and 0.44). In contrast, after the technical training, athletes demonstrated a possible increase in the SJ and Vc in both muscles examined (effect sizes varying from 0.13 to 0.20). CONCLUSIONS: The main finding of this research is that, for the vast majority of results, the direction of changes observed in the Vc were the same as those observed in performance assessments. This suggests that the Vc might be used as a sensitive marker of acute variations in speed and power performance of elite team-sport athletes.

8.
J Strength Cond Res ; 2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-31009434

RESUMO

Loturco, I, Pereira, LA, Kobal, R, Fernandes, V, Reis, VP, Romano, F, Alves, M, Freitas, TT, and McGuigan, M. Transference effect of short-term optimum power load training on the punching impact of elite boxers. J Strength Cond Res XX(X): 000-000, 2019-This study examined the changes in bench press (BP), jump squat (JS), and half-squat (HS) power outputs induced by a short-term (1 week) training scheme based on the optimum power load (OPL) applied to national boxing athletes and measured the transference effect coefficient (TEC) of these exercises on punching impact. Eight elite boxing athletes from the Brazilian National team participated in this study. Athletes were tested before and after 3 power-oriented training sessions performed at the OPL. The physical assessments comprised punching impact measures (jabs and crosses) at fixed and self-selected distances, and bar-power output in BP, HS, and JS exercises. Magnitude-based differences were used to compare pre-training and post-training sessions. Transference effect coefficient was calculated as the ratio between the result gain in the "untrained exercises" (punching impact in jabs and crosses) and "trained exercises" (HS, JS, and BP), for variables presenting an effect size of at least 0.2. The OPL training elicited meaningful increases in the punching impact forces (∼8%) and in both JS and HS power outputs (∼12 and ∼14%, respectively), but not in BP power output. There was an effective transference (TEC = ∼0.80) of JS and HS performance gains to punching impact force, suggesting that increases in lower-limb power can be directly transferred to punching impact. These results provide coaches and practitioners with valuable information about how to rapidly and effectively increase the punching impact force of elite amateur boxers.

9.
J Strength Cond Res ; 33(4): 974-986, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30913203

RESUMO

Loturco, I, Kobal, R, Kitamura, K, Fernandes, V, Moura, N, Siqueira, F, Cal Abad, CC, and Pereira, LA. Predictive factors of elite sprint performance: influences of muscle mechanical properties and functional parameters. J Strength Cond Res 33(4): 974-986, 2019-Sprint performance relies on many different mechanical and physiological factors. The purpose of this study was to identify, among a variety of strength-power exercises and tensiomyography (TMG) parameters, the best predictors of maximum running speed in elite sprinters and jumpers. To test these relationships, 19 power track and field athletes, 4 long jumpers, and 15 sprinters (men: 12; 22.3 ± 2.4 years; 75.5 ± 8.3 kg; 176.5 ± 5.6 cm; women: 7; 23.8 ± 4.2 years; 56.9 ± 5.4 kg; 167.4 ± 5.8 cm) were assessed using different intensities of TMG-derived velocity of contraction (Vc), squat and countermovement jumps, drop jump at 45 and 75 cm; and a 60-meter sprint time. In addition, the mean propulsive power (MPP) and peak power (PP) outputs were collected in the jump squat (JS) and half-squat (HS) exercises. Based on the calculations of the Vc at 40 mA, the athletes were divided (by median split analysis) into 2 groups: higher and lower Vc 40 mA groups. The magnitude-based inference method was used to compare the differences between groups. The correlations between mechanical and functional measures were determined using the Pearson's test. A multiple regression analysis was performed to predict sprint performance, using the Vc at 40 mA, jump heights, and JS and HS power outputs as independent variables. The higher Vc 40 mA group demonstrated likely better performances than the lower Vc 40 mA group in all tested variables. Large to nearly perfect significant correlations were found between sprint time, jump heights, and power outputs in both JS and HS exercises. Notably, the Vc 40 mA associated with the vertical jump height and MPP in JS explained >70% of the shared variance in sprint times. In conclusion, it was found that faster athletes performed better in strength-power tests, in both loaded and unloaded conditions, as confirmed by the strong correlations observed between speed and power measures. Lastly, the Vc also showed a marked selective influence on sprint and power capacities. These findings reinforce the notion that maximum running speed is a very complex physical capacity, which should be assessed and trained using several methods and training strategies.


Assuntos
Desempenho Atlético , Força Muscular , Músculo Esquelético/fisiologia , Corrida/fisiologia , Adulto , Atletas , Teste de Esforço , Feminino , Humanos , Masculino , Análise Multivariada , Postura , Atletismo/fisiologia , Adulto Jovem
10.
Braz J Psychiatry ; 41(4): 324-335, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30843960

RESUMO

OBJECTIVE: To present the essential guidelines for pharmacological management of patients with psychomotor agitation in Brazil. METHODS: This is a systematic review of articles retrieved from the MEDLINE (PubMed), Cochrane Database of Systematic Reviews, and SciELO databases published from 1997 to 2017. Other relevant articles in the literature were also used to develop these guidelines. The search strategy used structured questions formulated using the PICO model, as recommended by the Guidelines Project of the Brazilian Medical Association. Recommendations were summarized according to their level of evidence, which was determined using the Oxford Centre for Evidence-based Medicine system and critical appraisal tools. RESULTS: Of 5,362 articles retrieved, 1,731 abstracts were selected for further reading. The final sample included 74 articles that met all inclusion criteria. The evidence shows that pharmacologic treatment is indicated only after non-pharmacologic approaches have failed. The cause of the agitation, side effects of the medications, and contraindications must guide the medication choice. The oral route should be preferred for drug administration; IV administration must be avoided. All subjects must be monitored before and after medication administration. CONCLUSION: If non-pharmacological strategies fail, medications are needed to control agitation and violent behavior. Once medicated, the patient should be monitored until a tranquil state is possible without excessive sedation. SYSTEMATIC REVIEW REGISTRY NUMBER: CRD42017054440.


Assuntos
Antipsicóticos/administração & dosagem , Benzodiazepinas/administração & dosagem , Guias de Prática Clínica como Assunto , Agitação Psicomotora/tratamento farmacológico , Antipsicóticos/classificação , Benzodiazepinas/classificação , Brasil , Gerenciamento Clínico , Humanos , Escalas de Graduação Psiquiátrica , Agitação Psicomotora/diagnóstico
11.
Pediatr Exerc Sci ; 31(3): 306-313, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30736711

RESUMO

PURPOSE: To compare the effects of plyometric drop jump (DJ) training against those induced by regular soccer training and assess the transference effect coefficient (TEC) of DJs ("trained exercises") performed from 20- (DJ20) and 40-cm (DJ40) height boxes with respect to different physical qualities (jumping, linear and change of direction speed, kicking, endurance, and maximal strength) in youth male soccer players. METHODS: Participants were randomly divided into a control group (n = 20; age: 13.5 [1.9] y) and a DJ training group (n = 19; age: 13.2 [1.8] y), and trained for 7 weeks. A 2-way analysis of variance for repeated measures with the within-subject factor time (preintervention and postintervention) and between-subject factor group (intervention vs control) was performed. To calculate the TECs between the trained exercises (DJ20 and DJ40) and the physical tests, the ratio between the "result gains" (effect size [ES]) in the analyzed physical qualities and the result gains in the trained exercises were calculated. The TECs were only calculated for variables presenting an ES ≥ 0.2. RESULTS: Significant improvements (ES = 0.21-0.46; P < .05) were observed in the DJ training group, except in linear sprint performance. The control group improved only the maximal strength (ES = 0.28; P < .05). Significant differences were observed in all variables (ES = 0.20-0.55; P < .05) in favor of the DJ training group, except for maximal strength (group × time interaction). CONCLUSIONS: A plyometric training scheme based on DJs was able to significantly improve the physical performance of youth male soccer players. Overall, greater TECs were observed for DJ40 (0.58-1.28) than DJ20 (0.55-1.21).

12.
J Sports Sci ; : 1-7, 2019 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-30724662

RESUMO

This study examined the age-specific development of vertical jump height, straight and change-of-direction (COD) speed, and COD deficit in one-hundred and eighty-two elite soccer players from different age-categories (U15, U17, U20, and Senior). All participants were players of two distinct clubs and were undertaking different training routines, as planned by their technical staff members. For this purpose, the soccer players performed: (1) squat and countermovement jumps; (2) a maximal 20-m linear sprint speed test, and (3) the Zigzag COD test. The magnitude-based inference approach and standardized differences were used to compare the age-groups. Sprint speed at longer distances (20-m) increased progressively across the age-ranges. In contrast, speed and acceleration performances at shorter distances (5-m) were better in U15 than in the other age-categories. The COD speed did not change throughout the younger categories but presented a meaningful decrease in the Senior category. Surprisingly, despite the progressive increase in volume and intensity of neuromuscular training from younger to older categories, the COD deficit presented a gradual increase across the age-groups. It is possible that simple modulation of the strength-power training program during the maturation process is not sufficient to produce faster adult players with enhanced ability to change direction. Therefore, coaches are strongly encouraged to implement specific COD training practices to tolerate braking at increasing running speeds and appropriate volume and intensity of soccer specific training throughout the players' specialization process.

13.
Braz J Psychiatry ; 41(2): 153-167, 2019 Mar-Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30540028

RESUMO

OBJECTIVE: To present the essential guidelines for non-pharmacological management of patients with psychomotor agitation in Brazil. METHODS: These guidelines were developed based on a systematic review of articles published from 1997 to 2017, retrieved from MEDLINE (PubMed), Cochrane Database of Systematic Review, and SciELO. Other relevant articles identified by searching the reference lists of included studies were also used to develop these guidelines. The search strategy used structured questions formulated using the PICO model, as recommended by the Guidelines Project of the Brazilian Medical Association. Recommendations were summarized according to their level of evidence, which was determined using the Oxford Centre for Evidence-based Medicine system and critical appraisal tools. RESULTS: We initially selected 1,731 abstracts among 5,362 articles. The final sample included 104 articles that fulfilled all the inclusion criteria. The management of agitated patients should always start with the least coercive approach. The initial non-pharmacological measures include a verbal strategy and referral of the patient to the appropriate setting, preferably a facility designed for the care of psychiatric patients with controlled noise, lighting, and safety aspects. Verbal de-escalation techniques have been shown to decrease agitation and reduce the potential for associated violence in the emergency setting. The possibility of underlying medical etiologies must be considered first and foremost. Particular attention should be paid to the patient's appearance and behavior, physical signs, and mental state. If agitation is severe, rapid tranquilization with medications is recommended. Finally, if verbal measures fail to contain the patient, physical restraint should be performed as the ultimate measure for patient protection, and always be accompanied by rapid tranquilization. Healthcare teams must be thoroughly trained to use these techniques and overcome difficulties if the verbal approach fails. It is important that healthcare professionals be trained in non-pharmacological management of patients with psychomotor agitation as part of the requirements for a degree and graduate degree. CONCLUSION: The non-pharmacological management of agitated patients should follow the hierarchy of less invasive to more invasive and coercive measures, starting with referral of the patient to an appropriate environment, management by a trained team, use of verbal techniques, performance of physical and mental assessment, use of medications, and, if unavoidable, use of the mechanical restraint. SYSTEMATIC REVIEW REGISTRY NUMBER: CRD42017054440.


Assuntos
Gerenciamento Clínico , Guias de Prática Clínica como Assunto , Agitação Psicomotora/diagnóstico , Agitação Psicomotora/terapia , Brasil , Humanos , Escalas de Graduação Psiquiátrica
14.
J Hum Kinet ; 64: 205-218, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30429912

RESUMO

This study aimed to compare vertical jump ability (squat-jump [SJ] and countermovement-jump [CMJ]), relative to body mass mean propulsive power in the jump-squat (MPP-REL JS), and the 0-5, 5-10, and 10-20 m acceleration and speed among soccer players from the same professional club, divided into age-categories (U15 [n = 20], U17 [n = 53], U20 [n = 22] and senior [n = 25] players). The tests were performed at the start of the preseason in indoor facilities. The magnitude-based inference approach and the standardized differences (based on effect sizes) were used to compare the age-groups. The SJ, CMJ, and MPP-REL JS increased across the age-groups up to U20, the latter being similar to senior players. Interestingly, the 0-5 m acceleration was likely and possibly higher in U15 players compared to U17 and senior players. Although soccer athletes improve their unloaded and loaded jump abilities across the age-categories (plateauing during adulthood), the same does not hold true for acceleration capacity, from the early phases of players' development (i.e., U15). Strength and conditioning professionals should seek effective strategies to minimize impairment in maximal acceleration performance of elite soccer players throughout their prospective training programs.

15.
J Hum Kinet ; 63: 85-94, 2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-30279944

RESUMO

The aim of this study was to compare and examine differences in several neuromuscular assessments between female national Olympic team (Rio-2016) and national college team handball players (2015-Gwangju Summer Universiade). Twenty-eight elite female handball players of the national Brazilian Olympic (n = 12) and college (n = 16) teams participated in this study. The Olympic and college athletes performed the following speed-power tests assessing mean propulsive power (MPP) in loaded jump squat (JS) and bench press (BP) exercises, unloaded squat and countermovement jumps (SJ and CMJ), sprint performance over 5-, 10-, and 20-m, and change of direction ability in a standard Zig-zag test and a T-Test. The differences between Olympic and college team performances in all variables were analyzed using the magnitude-based inference. The Olympic group presented likely higher performances in the SJ, CMJ, and MPP JS and very likely higher performances in the MPP BP and T-Test than the college group. The differences in the linear sprint velocity in 5-, 10-, and 20-m tests as well as in the Zig-zag test were all rated as unclear. These findings may have substantial implications for the development of effective strength-power training and testing strategies in elite handball. In addition, coaches and researchers can use these data to create efficient talent identification programs for youth handball players.

16.
Int J Sports Physiol Perform ; : 1-13, 2018 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-30204509

RESUMO

PURPOSE: This study examined the relationships between different loading intensities and movement velocities in the bench-press exercise (BP) in Paralympic powerlifters. METHODS: Seventeen National Paralympic powerlifters performed maximum dynamic strength tests to determine their BP one-repetition maximum (1RM) in a Smith-machine device. A linear position transducer was used to measure the movement velocity over a comprehensive range of loads. Linear regression analysis was performed to establish the relationships between the different bar-velocities and the distinct percentages of 1RM (%1RM). RESULTS: Overall, the correlations between bar-velocities and %1RM were strong over the entire range of loads (R² values ranged from 0.80 to 0.91), but the precision of the predictive equations (expressed as mean differences [%] between actual and predicted 1RM values) were higher at heavier loading intensities (~20% for loads ≤ 70% 1RM, and ~5% for loads ≥ 70%1RM). In addition, it seems that these very strong athletes (e.g., 1RM relative in the BP = 2.22 ± 0.36 kg.kg-1, for male participants) perform BP 1RM assessments at lower velocities than those previously reported in the literature. CONCLUSIONS: The load-velocity relationship was strong and consistent in Paralympic powerlifters, especially at higher loads (≥ 70% 1RM). Therefore, Paralympic coaches can use the predictive equations and the reference values provided here to determine and monitor the BP loading intensity in National Paralympic powerlifters.

17.
Sports (Basel) ; 6(3)2018 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-30217089

RESUMO

The purpose of this case study was to examine the effects of a resistance-training program based on the optimum power loads (OPL) method on neuromuscular performance of Olympic boxing athletes during preparation for the Rio-2016 Olympic Games. Twelve elite amateur boxers from the Brazilian National Olympic Team participated in this study. Athletes were assessed at four time-points, over two consecutive competitive seasons. In the first season (considered as "control period"), the athletes executed a non-controlled strength-power training program for 10 weeks. In the second season (a seven-week experimental period), the elite boxers performed 14 power-oriented training sessions, comprising bench press (BP) and jump squat (JS) exercises at the OPL. Maximum bar-power output in BP and JS exercises was measured pre and post both training phases. Magnitude-based inferences were used to compare changes in pre and post training tests. Bar-power outputs increased meaningfully in both BP (+8%) and JS (+7%) exercises after the OPL training program. In contrast, after the control period, no worthwhile improvements were observed in the variables tested. Based on the findings of this study, highly trained boxers might benefit from the use of a training scheme based on OPL.

18.
J Sports Sci Med ; 17(3): 372-378, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30116110

RESUMO

The aim of this single-blind randomized controlled trial was to compare the effects of plyometric jump training (PJT), with (RG) and without (NRG) between-session drill randomization, on performance measures (i.e., jumping and sprinting abilities, change of direction speed, and technical performance) in youth male basketball players (age, 10.2 ± 1.7 years), assigned to either the NRG (n = 7), RG (n = 6), or control group (n = 6). Before and after the intervention, countermovement jump, 20-cm drop jump, 30-m sprint (with or without ball dribbling), and change-of-direction speed tests were completed. The PJT was applied twice per week for seven weeks. The only difference between PJT groups was the order of drill execution. An ANOVA was used to detect differences between study groups. The analyses revealed significant main effects of time (all p<.01; d = 0.64-0.89) and group x time interaction (all p<.05; d=0.31-51) for all examined variables. Post hoc analyses revealed moderate-large significant improvements for the RG (countermovement jump: 18.8%, d = 0.6; 20-cm drop jump: 23.9%, d = 0.80; 30-m sprint: 11.6%, d = 1.13; 30-m sprint with ball dribbling: 9.3%, d = 0.54; change of direction speed test: 14.6%, d = 1.82). In contrast, post hoc analyses revealed only small improvements for the NRG (20-cm drop jump: 14.1%, d = 0.36; 30-m sprint: 6.8%, d = 0.45; 30-m sprint with ball dribbling: 8.8%, d = 0.35; change of direction speed test: 10.5%, d = 0.49). Application of PJT without randomization is effective for improving physical and technical qualities. However, PJT could be more beneficial when executed with between-session randomization of drills.

19.
J Sports Sci ; : 1-8, 2018 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-29983101

RESUMO

This study aimed to compare the power production in traditional bench-press (TBP) and ballistic bench-throw (BBT) exercises. Furthermore, we assessed the differences in velocity, force, and power outputs between TBP and BBT. Finally, we tested the differences between the loads used to optimize power (optimum power load; OPL) in both exercises, using three distinct power-variables: mean power (MP), mean propulsive power (MPP), and peak power (PP). Sixty athletes from different sports were divided into two groups, according to their training characteristics: hypertrophy-based trained athletes (HTA), thirty-one athletes performing hypertrophy training programmes for (at least) 12-weeks; and power-based trained athletes (PTA), twenty-nine athletes performing power-oriented training sessions for (at least) 12-weeks. Magnitude-based inferences were used to test for differences between groups. Independent of the variable analyzed (MP, MPP, or PP), the PTA produced greater power values in BBT, whereas the HTA generated higher outputs during TBP. The OPL in the HTA was likely heavier in TBP than in BBT, whereas no differences related to this variable were found in the PTA. Despite the apparent superiority of ballistics to produce power, it seems that in elite athletes, the strength-power training routine might affect the ability to apply high forces at very-high velocities.

20.
Sports (Basel) ; 6(3)2018 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-30002328

RESUMO

This study aimed to examine the associations between a series of mechanical variables automatically generated by a portable force plate (PFP) and the actual performance of professional sprinters over a 150 m course. To test these correlations, 12 top-level sprinters performed vertical jumps (squat and countermovement jumps; SJ and CMJ, respectively), a 60 m sprint test, and a 150 m sprint test. Pearson product-moment coefficient of correlation and multiple regression analyses were used to determine the relationships between the sprinting velocities and vertical jump outputs. The SJ parameters were moderately to near perfectly associated with the different sprint distances, and the SJ height presented the highest correlation scores (r = 0.90 with velocities over 10- and 20-m). The correlation coefficients between the CMJ outcomes and sprint results varied between moderate and very large (from 0.38 to 0.88). Finally, the coefficients of determination (R²) ranged from 0.71 to 0.85 for the different multiple regressions involving PFP automatic measures. The PFP can provide practitioners with quick and accurate information regarding competitive athletes. Due to the strong correlations observed, coaches are encouraged to frequently adjust and tailor the training strategies of their sprinters, using practical and timesaving PFP measurements.

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