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The purpose of this study was to examine the effects of a 26-week on-field combined strength and high-intensity training on the physical performance capacity among prepubertal soccer players who were undertaking a competitive phase of training. Twenty-four prepubertal soccer players between the age of 8 and 9 years were randomly assigned to 2 groups: a control (C; n = 13) and an experimental group (S; n = 11). Both groups performed an identical soccer-training program, whereas the S group also performed combined strength and high-intensity training before the soccer-specific training. The 15-m sprint time (seconds), countermovement jump (CMJ) displacement, Yo-Yo intermittent endurance test (Yo-Yo IE), and Sit and Reach flexibility were each measured before (baseline) and after 9 (T2), 18 (T3), and 26 weeks (posttest) of training. There were no significant differences between the groups in any of the variables tested at baseline. After 26 weeks, significant improvements were found in the CMJ (6.72%; effect size [ES] = 0.37), Yo-Yo IE (49.57%, ES = 1.39), and Flexibility (7.26%; ES = 0.37) variables for the S group. Conversely, significant decreases were noted for the CMJ (-10.82%; ES = 0.61) and flexibility (-13.09%; ES = 0.94) variables in the C group. A significant negative correlation was found between 15-m sprint time and CMJ (r = -0.77) and Yo-Yo IE (r = -0.77) in the S group. Specific combined strength and high-intensity training in prepubertal soccer players for 26 weeks produced a positive effect on performance qualities highly specific to soccer. Therefore, we propose modifications to current training methodology for prepubertal soccer players to include strength and high-intensity training for athlete preparation in this sport.
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Desempenho Atlético/fisiologia , Condicionamento Físico Humano/fisiologia , Treinamento Resistido , Corrida/fisiologia , Futebol/fisiologia , Criança , Humanos , Força Muscular , Músculo Esquelético/fisiologia , Condicionamento Físico Humano/métodos , Resistência Física/fisiologiaRESUMO
We compared the effects of 6-week dry-land and in-water specific strength training combined with a water polo (WP) program on 7 sport-specific performance parameters. Nineteen professional players were randomly assigned to 2 groups: in-water strength group (WSG) (in-water training only) and dry-land strength group (LSG). The program included 3 weekly strength training sessions and 5 days of WP training per week for 6 weeks during the preseason. Ten-meter T-agility test, 20-m maximal sprint swim, maximal dynamic strength (1 repetition maximum), bench press (BP) and full squat (FS), in-water boost, countermovement jump (CMJ), and WP throwing speed were measured. Significant improvements (p ≤ 0.05) were found in the experimental groups in some variables: CMJ in the LSG and WSG (2.35 cm, 9.07%, effect size [ES] = 0.89; and 2.6 cm, 7.6%, ES = 0.83, respectively), in-water boost increased in the WSG group (4.1 cm; 11.48%; ES = 0.70), and FS and BP increased (p ≤ 0.05) only in the LSG group (12.1 kg; 11.27%; ES = 1.15 and 8.3 kg; 9.55%; ES = 1.30, respectively). There was a decrease of performance in agility test (-0.55 seconds; 5.60%; ES = 0.74). Both dry-land and in-water specific strength training and high-intensity training in these male WP players produced medial to large effects on most WP-specific performance parameters. Therefore, we propose modifications to current training methodology for WP players in preseason to include both the training programs (dry-land and in-water specific strength training and high-intensity training) for athlete preparation in this sport.
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Desempenho Atlético/fisiologia , Condicionamento Físico Humano/métodos , Treinamento Resistido/métodos , Esportes/fisiologia , Água , Adolescente , Adulto , Teste de Esforço , Humanos , Masculino , Força Muscular , Condicionamento Físico Humano/fisiologia , Natação/fisiologia , Adulto JovemRESUMO
BACKGROUND: Two specific sprint training methods that are present to varying degrees in research and practice are combined uphill-downhill sprinting (UDS) and resisted sprint training methods (RS). Both methods seem to improve sprint performance, but to the author's knowledge a comparison does not exist investigating the differences between the two training protocols and traditional sprinting. OBJECTIVE: The present systematic review and meta-analysis investigated sprint performance changes between combined uphill-downhill sprinting and resisted sprinting methods (sleds, cables/bands, vests, uphill) and how these compared with traditional sprinting. METHODS: A literature search was performed on 19 December 2022, in the databases PubMed, SPORTDiscus, Web of Science and SCOPUS, which from 22 studies yielded a total of 24 eligible groups (UDS, n = 6; RS, n = 18). Studies that measured sprint performance, had a traditional sprinting control, and used either training intervention in healthy individuals of any age for ≥ 4 weeks were eligible for the meta-analysis. The change in sprint performance from baseline to post intervention was compared between the interventions and their traditional sprinting control group. Outcomes were expressed as standardized mean differences (SMD). RESULTS: The standardized changes in sprint performance between intervention groups and traditional-sprinting controls (negative in favour of intervention, positive in favour of traditional sprint) and 95% confidence interval (CI) were as follows: small for UDS (SMD - 0.41 [- 0.79, - 0.03]; p = 0.03), trivial for RS (SMD - 0.14 [- 0.36, 0.07]; p = 0.19). CONCLUSION: Combined uphill-downhill sprinting was more effective than traditional sprinting, while resisted sprinting was not. It appears that resisted sprint interventions do not increase sprint performance any more than traditional sprinting. Subgroup analysis and meta-regression appear to show differences between sled loads and possible differences across distances tested. The results of this review and meta-analysis seem to warrant further investigations into the possibility that UDS may be a superior sprint training method to resisted and traditional sprinting.
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Desempenho Atlético , Treinamento Resistido , Corrida , Humanos , Nível de Saúde , Treinamento Resistido/métodosRESUMO
The objective of this study was to assess the perceived usefulness, actual use and limitations for the application of recovery strategies among water polo (WP) players and their coaches around the world. A total of 231 WP players and 76 coaches representing all continents, both genders and all levels of competition, completed a freely accessible online survey. This was divided into three sections: sociodemographic data (8 questions), importance of perceived usefulness of recovery strategies (3 questions), and actual use of recovery methods (6 questions). The majority of players and coaches considered recovery strategies as very important (52.4% and 59.2%, respectively) and posttraining session (28.1% and 26.5%) were the most frequently used times. The most selected reasons to justify their use were to reduce the injury risk (30.4% and 26.9%) and the most limitation to the use of recovery strategies were that they are too time-consuming (34.9% and 29%). In the case of the players, stretching were the strategies perceived as most useful and used (12.7% and 18.1%); and in the case of the coaches, it was active recovery (11.2% and 15%). The present study suggests a degree of discrepancy between the scientific literature and the research participants' perceptions and usages of recovery methods. This information may be of interest for coaches and technical staff of WP teams to look for appropriate recovery strategies for the improvement of their players' performance.
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This study compared the effects of a 6-week combined plyometric and sprint-training program on the sand to regular preseason training, on the athletic performance and technical actions of beach handball (BH) players. Athletes were randomly assigned either to the control (CG, n = 12; BH training only) or the experimental group (EG, n = 12; plyometric + sprint + BH training). Assessments conducted before and after the training period included a squat jump, a countermovement jump, the Abalakov jump, a 15-m sprint, a modified Course-Navette endurance test, and four sport-specific BH throwing speed tests: a standing penalty throw, a 3-step running throw, a jump throw, and a 360º jump throw. The training intervention enhanced all athletic performance measures (all, p < 0.05). In contrast, the only improvement in the CG included endurance performance (p< 0.05). Significant time-group differences were noted in favor of the EG compared to the CG (p< 0.05) in the squat jump, the countermovement jump, the Abalakov jump, the jump throw velocity and 360º jump throw velocity. In conclusion, compared to BH regular training, 6 weeks of sand surface preseason plyometric and sprint training combined with regular BH training induced greater improvements in athletic performance and specific skills in BH players.
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This article includes four separate experiments. In the first experiment male beach handball players (n = 24) were randomly assigned to regular training (n = 12) or plyometric and sprint training (n = 12). In the second experiment, male players were assigned to a handball practice only (n = 12), a plyometric training (n = 12), or an eccentric-overload (e.g., versa-pulley machine) training group (n = 12). In the third experiment, participants were assigned to padel training (n = 12) or specific on-court neuromuscular technical actions (n = 12). In the fourth experiment, females between 50-59 years (n = 25), 60-64 years (n = 25), and 65-70 years (n = 25) completed 10 weeks of bench stepping training involving jumps, and were compared to age-matched controls (n = 45). The COD ability was assessed with the 10-m COD ability test (experiments one and two), the COD ability test with 90º and 180º turns (third experiment), and with the timed-up-and-go test (fourth experiment). In experiment one, greater COD improvement was noted in the experimental group compared to the control group (p < 0.05). In experiment two, both intervention groups similarly improved COD when compared to the control group (p < 0.05). In experiment three, although no significant group-time interactions were observed for COD, the experimental group improved all COD measures pre-post-training (p < 0.05), with a larger effect size for COD with 180° turn to the right compared to the control group (effect size = 0.8 vs. 0.3). In experiment four, the three training groups improved COD ability compared to the control group (p < 0.05). In conclusion, COD is a sensitive marker of adaptation to different training configurations in these diverse groups.
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Water polo (WP) is a high-intensity intermittent aquatic sport, with a predominance of swimming skills and nonswimming activities and incomplete recovery periods. Consequently, recovery after exercise is a fundamental part of sports performance. The main purpose of this systematic review was to evaluate the effects of different recovery strategies in WP performance. The studies were found by searching in the databases of PubMed, Web of Science, and Scopus. Methodological quality and risk of bias were assessed in accordance with the Cochrane Collaboration Guidelines samples. A summary of results including five studies was followed. The results show that supplementation with cherry juice before training does not imply improvements in recovery; the full-body photobiomodulation therapy reduces muscle damage; reducing training load during the season increased the natural logarithm of the root mean square of successive differences and perceived state of recovery, and the heart rate variability stabilizes and could progressively increase at the end of a tournament; and when an increase in internal training load is less than 60%-70% autonomic cardiac disturbances during preseason training do not occur. Recovery in WP is a very limited field of study that needs future research in active recovery, hydrotherapy, massage, rest and sleep to help coaches formulate recommendations.
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BACKGROUND: A growing body of literature is available regarding the effects of plyometric jump training (PJT) on measures of physical fitness (PF) and sport-specific performance (SSP) in-water sports athletes (WSA, i.e. those competing in sports that are practiced on [e.g. rowing] or in [e.g. swimming; water polo] water). Indeed, incoherent findings have been observed across individual studies making it difficult to provide the scientific community and coaches with consistent evidence. As such, a comprehensive systematic literature search should be conducted to clarify the existent evidence, identify the major gaps in the literature, and offer recommendations for future studies. AIM: To examine the effects of PJT compared with active/specific-active controls on the PF (one-repetition maximum back squat strength, squat jump height, countermovement jump height, horizontal jump distance, body mass, fat mass, thigh girth) and SSP (in-water vertical jump, in-water agility, time trial) outcomes in WSA, through a systematic review with meta-analysis of randomized and non-randomized controlled studies. METHODS: The electronic databases PubMed, Scopus, and Web of Science were searched up to January 2022. According to the PICOS approach, the eligibility criteria were: (population) healthy WSA; (intervention) PJT interventions involving unilateral and/or bilateral jumps, and a minimal duration of ≥ 3 weeks; (comparator) active (i.e. standard sports training) or specific-active (i.e. alternative training intervention) control group(s); (outcome) at least one measure of PF (e.g. jump height) and/or SSP (e.g. time trial) before and after training; and (study design) multi-groups randomized and non-randomized controlled trials. The Physiotherapy Evidence Database (PEDro) scale was used to assess the methodological quality of the included studies. The DerSimonian and Laird random-effects model was used to compute the meta-analyses, reporting effect sizes (ES, i.e. Hedges' g) with 95% confidence intervals (95% CIs). Statistical significance was set at p ≤ 0.05. Certainty or confidence in the body of evidence for each outcome was assessed using Grading of Recommendations Assessment, Development, and Evaluation (GRADE), considering its five dimensions: risk of bias in studies, indirectness, inconsistency, imprecision, and risk of publication bias. RESULTS: A total of 11,028 studies were identified with 26 considered eligible for inclusion. The median PEDro score across the included studies was 5.5 (moderate-to-high methodological quality). The included studies involved a total of 618 WSA of both sexes (330 participants in the intervention groups [31 groups] and 288 participants in the control groups [26 groups]), aged between 10 and 26 years, and from different sports disciplines such as swimming, triathlon, rowing, artistic swimming, and water polo. The duration of the training programmes in the intervention and control groups ranged from 4 to 36 weeks. The results of the meta-analysis indicated no effects of PJT compared to control conditions (including specific-active controls) for in-water vertical jump or agility (ES = - 0.15 to 0.03; p = 0.477 to 0.899), or for body mass, fat mass, and thigh girth (ES = 0.06 to 0.15; p = 0.452 to 0.841). In terms of measures of PF, moderate-to-large effects were noted in favour of the PJT groups compared to the control groups (including specific-active control groups) for one-repetition maximum back squat strength, horizontal jump distance, squat jump height, and countermovement jump height (ES = 0.67 to 1.47; p = 0.041 to < 0.001), in addition to a small effect noted in favour of the PJT for SSP time-trial speed (ES = 0.42; p = 0.005). Certainty of evidence across the included studies varied from very low-to-moderate. CONCLUSIONS: PJT is more effective to improve measures of PF and SSP in WSA compared to control conditions involving traditional sport-specific training as well as alternative training interventions (e.g. resistance training). It is worth noting that the present findings are derived from 26 studies of moderate-to-high methodological quality, low-to-moderate impact of heterogeneity, and very low-to-moderate certainty of evidence based on GRADE. Trial registration The protocol for this systematic review with meta-analysis was published in the Open Science platform (OSF) on January 23, 2022, under the registration doi https://doi.org/10.17605/OSF.IO/NWHS3 (internet archive link: https://archive.org/details/osf-registrations-nwhs3-v1 ).
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Sáez Sáez de villarreal, E, Izquierdo, M, and Gonzalez-Badillo, JJ. Enhancing jump performance after combined vs. maximal power, heavy-resistance, and plyometric training alone. J Strength Cond Res 25(12): 3274-3281, 2011-The purpose of this study was to examine the effects of 5 different stimuli on jumping ability and power production after 7 weeks of training. Sixty-five (47 men and 18 women) physical education students were randomly assigned to 5 experimental groups that performed: combination of all training methods (A); heavy-resistance training using full-squat exercise (i.e., 56-85% of 1 RM for 3-6 repetitions) (B); power-oriented strength training using a parallel-squat exercise (i.e., 100-130% of load that maximizes power output for 2-6 repetitions) (C); power-oriented strength training using a loaded countermovement jumping (i.e., 70-100% of load that maximizes power output for 2-5 repetitions; countermovement jump [CMJ]) (D); and plyometric jumping (E). The CMJ (cm), loaded CMJ (cm), maximum rate of force development (RFDmax) during early concentric phase of loaded CMJ (N·s) and power output during early concentric phase of loaded CMJ (watts) were measured before and after 7 weeks of training. Significant improvements in CMJ (from 7.8 to 13.2%) were observed in all groups. Significantly greater increases in power output during loaded jumps were observed in A (10-13%) and D (8-12%) groups compared with in the other groups. Significant increases in RFDmax were observed in A (20-30%), C (18-26%), and D (20-26%) groups. The results of this study provide evidence to suggest that if training program is designed and implemented correctly, both traditional slow velocity training and faster power-oriented strength training alone, or in combination with plyometric training, would provide a positive training stimulus to enhance jumping performance.
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Desempenho Atlético/fisiologia , Movimento , Educação Física e Treinamento/métodos , Exercício Pliométrico , Treinamento Resistido , Adolescente , Adulto , Antropometria , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Força Muscular , Músculo Esquelético/fisiologia , Adulto JovemRESUMO
The purpose of this study was to quantify the magnitude of the relationship between vertical jumping and maximal sprinting at different distances with performance in the traditional and ballistic concentric squat exercise in well-trained sprinters. Twenty-one men performed 2 types of barbell squats (ballistic and traditional) across different loads with the aim of determining the maximal peak and average power outputs and 1 repetition maximum (1RM) values. Moreover, vertical jumping (countermovement jump test [CMJ]) and maximal sprints over 10, 20, 30, 40, 60, and 80 m were also assessed. In respect to 1RM in traditional squat, (a) no significant correlation was found with CMJ performance; (b) positive strong relationships (p < 0.01) were obtained with all the power measures obtained during both ballistic and traditional squat exercises (r = 0.53-0.90); (c) negative significant correlations (r = -0.49 to -0.59, p < 0.05) were found with sprint times in all the sprint distances measured when squat strength was expressed as a relative value; however, in the absolute mode, no significant relationships were observed with 10- and 20-m sprint times. No significant relationship was found between 10-m sprint time and relative or absolute power outputs using either ballistic or traditional squat exercises. Sprint time at 20 m was only related to ballistic and traditional squat performance when power values were expressed in relative terms. Moderate significant correlations (r = -0.39 to -0.56, p < 0.05) were observed between sprint times at 30 and 40 m and the absolute/relative power measures attained in both ballistic and traditional squat exercises. Sprint times at 60 and 80 m were mainly related to ballistic squat power outputs. Although correlations can only give insights into associations and not into cause and effect, from this investigation, it can be seen that traditional squat strength has little in common with CMJ performance and that relative 1RM and power outputs for both squat exercises are statistically correlated to most sprint distances underlying the importance of strength and power to sprinting.
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Exercício Físico/fisiologia , Corrida/fisiologia , Levantamento de Peso/fisiologia , Adulto , Atletas , Desempenho Atlético/fisiologia , Humanos , Masculino , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Adulto JovemRESUMO
PURPOSE: This study aimed to compare the effects of 5 different 18-week in-season strength training programs on strength gains and specific water polo performance. METHODS: A total of 56 young male water polo players were randomly assigned to the following 5 training groups: dry-land strength training, in-water-specific strength training, combined (dry-land and in-water) strength training, ballistic training, and eccentric-overload training. Physical performance was assessed before (Pre) and after (Post) the training period using the following battery of tests: in-water boost and countermovement jump, muscle strength in bench-press and full-squat, throwing speed (ThS), in-water agility, and 20-m maximal sprint swim. RESULTS: Significant group × time interactions were observed for countermovement jump and in-water boost. Eccentric-overload training showed significantly higher gains in ThS and bench-press and full-squat strength than the rest of the training groups. In addition, all training groups (except in-water-specific strength training) induced significant improvements (P ≤ .05) in countermovement jump, in-water boost, and bench-press and full-squat strength. All training groups significantly increased (P ≤ .001) ThS. Moreover, all training groups improved (P ≤ .05) in-water agility (except dry-land strength training) and swimming sprint performance (except in-water-specific strength training and ballistic training). CONCLUSION: The findings indicate that the 18-week in-season strength training programs induced improvements in strength and specific water polo skills. The eccentric-overload training resulted in greater improvements in muscle strength (in both upper and lower body) and ThS than the other training methods examined in the study.
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Desempenho Atlético , Treinamento Resistido , Humanos , Masculino , Força Muscular , Estações do Ano , NataçãoRESUMO
The aim of this study was to assess antioxidant markers before and after a mid-season of professional soccer players from the 3rd Spanish Division, and to correlate antioxidant markers with competitive performance. Sixty-five male players (age = 25.3 ± 4.2 yr, body mass = 73.2 ± 6.7 kg, body height = 177.8 ± 5.7 cm) from three soccer clubs from Cádiz (Spain) participated in the study. Body composition, maximal aerobic capacity (VO2max), and baseline antioxidant blood markers (Total Antioxidant Status (TAS) and Reduced glutathione/Oxidized glutathione ratio) were assessed in the first week of the championship season (pre-test) and after 18 weeks in the mid-season (post-test). Soccer performance was registered according to the official classification ranking at both the mid-season and at the end of the season; ranking positions for Team A were 2nd and 1st, for Team B were 5th and 5th, while for Team C were 12th and 14th, respectively. Regression analyses showed that TAS and VO2max were able to independently predict (p < 0.05) performance in our participants. Moreover, antioxidant levels showed significant main effects on performance (p < 0.001); where a higher antioxidant capacity was observed in the best performance soccer team, both before and after the mid-season. Notwithstanding, the competitive period compromised the antioxidant status since TAS levels significantly decreased after the 18-week training program and competition compared with baseline values in all soccer teams (p < 0.001). These results suggest the need of monitoring antioxidants in soccer players to prevent excessive oxidative stress and cellular damage which could compromise success in competition, by adjusting the training loads, diet or ergogenic aids, if needed.
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The purpose of this study was to determine the best prediction factors of traditional rowing performance in traditional elite (ER) and amateur (AR) rowers. Average power during the 20-min all-out test (W(20 min)), average power output which elicited a blood lactate concentration of 4 mmol l(-1) (W(4 mmol l(-1))), power output in 10 maximal strokes (W(10 strokes)), maximal strength and muscle power output during a bench pull (BP) and anthropometric values were all measured for 46 trained male rowers aged 21-30 with 8-15 years of rowing training experience. The ER group showed greater body mass (5%, p < 0.05), greater fat free body mass (5%, p < 0.05), greater 1RM(BP) (13%, p < 0.001), longer training experience (43%, p < 0.001), and a shorter time in the 2,000 m test (4%, p < 0.05) than the AR group. The ER group showed higher power output values in W(10 strokes) (9%, p < 0.01), W(20 min) (15.4%, p < 0.01) and (W(4 mmol l(-1))) (17.8%, p < 0.01) compared with the AR group. Significant relationships were observed between (W(4 mmol l(-1))) and W(20 min) (r = 0.65 and 0.80; p < 0.01 in ER and AR, respectively). The indices for rowing performance suggested that W(20 min), (W(4 mmol l(-1))), W(10 strokes) and 1RM(BP) were the most important predictors of traditional rowing performance in elite and amateur rowers.
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Desempenho Atlético/fisiologia , Lactatos/metabolismo , Aptidão Física/fisiologia , Ventilação Pulmonar/efeitos dos fármacos , Ventilação Pulmonar/fisiologia , Aerobiose/efeitos dos fármacos , Atletas , Exercício Físico/fisiologia , Teste de Esforço , Humanos , Perna (Membro) , Masculino , Consumo de Oxigênio/fisiologia , Resistência Física , Esforço Físico , Aptidão Física/psicologia , Navios/métodosRESUMO
BACKGROUND: Even from a young age, modern soccer requires high levels of physical fitness development, particularly jumping and sprinting. Plyometric jump training (PJT), combined with young athletes' regular soccer sessions, has the potential to improve jumping and sprinting. However, studies exploring the effects of PJT are generally limited by small sample sizes. This problem of underpowered studies may, thus, be resolved by pooling study results in a meta-analysis. OBJECTIVE: The objective of this systematic review with meta-analysis (SRMA) was to assess the effects of plyometric jump training (PJT) on jumping and sprinting among young male soccer players. METHODS: The SRMA included peer-reviewed articles that incorporated PJT in healthy players (i.e., < 23 years of age), a control group, and a measure of jumping or sprinting. Means and standard deviations of outcomes were converted to Hedges' g effect sizes (ES), using the inverse variance random-effects model. Moderator analyses were conducted for PJT duration, frequency, total number of sessions, participants' chronological age, and FIFA age categories (i.e., U-17 vs. U-20 vs. U-23). A multivariate random-effects meta-regression was also conducted. RESULTS: Thirty-three studies were included, comprising 1499 participants. PJT improved vertical jump tests (ES = 0.60-0.98; all p < 0.01) and linear sprint performance (ES = 0.60-0.98; p < 0.03). Interventions of > 7 weeks and > 14 PJT sessions induced greater effects compared to PJT with ≤ 7 weeks and ≤ 14 total sessions on 10-m sprint performance (between group p = 0.038). CONCLUSION: PJT is effective in improving jumping and sprinting performance among young male soccer players. Greater 10-m linear sprinting improvements were noted after interventions > 7-week duration and > 14 sessions, suggesting a greater return from exposure to longer PJT interventions, partially in support for the adoption of a long-term approach to athletic development in young athletes. However, with reference to the findings of the meta-regression, and those from the remaining subgroup and single factors analysis, a robust confirmation regarding the moderator role of participant's age or PJT configuration effects on young soccer player's fitness qualities needed.
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Desempenho Atlético , Exercício Pliométrico , Futebol , Atletas , Humanos , Masculino , Aptidão FísicaRESUMO
Plyometric training improves vertical jump height (VJH). However, the effectiveness of plyometric training depends on various factors. A meta-analysis of 56 studies with a total of 225 effect sizes (ESs) was carried out to analyze the role of various factors on the effects of plyometrics on VJH performance. The inclusion criteria for the analysis were a) studies using plyometric programs for lower-limb muscles, b) studies employing true experimental designs and valid and reliable measurements, and c) studies including enough data to calculate ESs. Subjects with more experience in sport obtained greater enhancements in VJH performance (p < 0.01). Subjects in either good or bad physical condition benefit equally from plyometric work (p < 0.05), although men tend to obtain better power results than women after plyometric training (p < 0.05). With relation to the variables of performance, training volumes of more than 10 weeks and more than 20 sessions, using high-intensity programs (with more than 50 jumps per session), were the strategies that seemed to maximize the probability of obtaining significantly greater improvements in performance (p < 0.05). To optimize jumping enhancement, the combination of different types of plyometrics (squat jump + countermovement jump + drop jump) is recommended rather than using only 1 form (p < 0.05). However, no extra benefits were found to be gained from doing plyometrics with added weight. The responses identified in this analysis are essential and should be considered by strength and conditioning professionals with regard to the most appropriate dose-response trends for optimizing plyometric-induced gains.
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Movimento/fisiologia , Força Muscular/fisiologia , Educação Física e Treinamento/métodos , Esportes/fisiologia , Análise de Variância , HumanosRESUMO
The purpose of this study was to examine the effect of 3 different plyometric training frequencies (e.g., 1 day per week, 2 days per week, 4 days per week) associated with 3 different plyometric training volumes on maximal strength, vertical jump performance, and sprinting ability. Forty-two students were randomly assigned to 1 of 4 groups: control (n = 10, 7 sessions of drop jump (DJ) training, 1 day per week, 420 DJs), 14 sessions of DJ training (n = 12, 2 days per week, 840 DJs), and 28 sessions of DJ training (n = 9, 4 days per week, 1680 DJs). The training protocols included DJ from 3 different heights 20, 40, and 60 cm. Maximal strength (1 repetition maximum [1RM] and maximal isometric strength), vertical height in countermovement jumps and DJs, and 20-m sprint time tests were carried out before and after 7 weeks of plyometric training. No significant differences were observed among the groups in pre-training in any of the variables tested. No significant changes were observed in the control group in any of the variables tested at any point. Short-term plyometric training using moderate training frequency and volume of jumps (2 days per week, 840 jumps) produces similar enhancements in jumping performance, but greater training efficiency (approximately 12% and 0.014% per jump) compared with high jumping (4 days per week, 1680 jumps) training frequency (approximately 18% and 0.011% per jump). In addition, similar enhancements in 20-m-sprint time, jumping contact times and maximal strength were observed in both a moderate and low number of training sessions per week compared with high training frequencies, despite the fact that the average number of jumps accomplished in 7S (420 jumps) and 14S (840 jumps) was 25 and 50% of that performed in 28S (1680 jumps). These observations may have considerable practical relevance for the optimal design of plyometric training programs for athletes, given that a moderate volume is more efficient than a higher plyometric training volume.
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Contração Isométrica/fisiologia , Força Muscular/fisiologia , Educação Física e Treinamento/métodos , Esportes/fisiologia , Adulto , Antropometria , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Fadiga Muscular/fisiologia , Resistência Física , Probabilidade , Fatores de Risco , Análise e Desempenho de Tarefas , Fatores de TempoRESUMO
PURPOSE: To analyze the match running profile, distance traveled over successive 15 min of match play, heart rates (HRs), and index of performance efficiency (effindex) of professional soccer players with a global positioning system (GPS) and HR in official competition. METHODS: Twenty-six professional players were investigated during full matches in competitive club-level matches (N = 223). Time-motion data and HR were collected using GPS and HR technology. RESULTS: The relative total distance was 113 ± 11 m/min, with substantial differences between halves. For all playing positions, a substantial decrease in total distance and distance covered at >13.0 km/h was observed in the second half in comparison with the first. The decrease during the second half in distance covered at >13.0 km/h was substantially higher than in total distance. The average HR recorded was 86.0% maximal HR, and the relationship between external and internal load (effindex) was 1.3, with substantial differences between halves in all playing positions, except strikers for effindex. Wide midfielders reflected substantially the lowest mean HR and highest effindex, whereas center backs showed substantially the lowest effindex of all playing positions. CONCLUSIONS: The current study confirmed the decrement in a player's performance toward the end of a match in all playing positions. Wide midfielders displayed the highest and fittest levels of physical and physiological demands, respectively, whereas center backs had the lowest and least-fit levels of physical and physiological demands, respectively. The position-specific relationship between external and internal load confirms that players with more overall running performance during the full match were the best in effindex.
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Desempenho Atlético/fisiologia , Comportamento Competitivo/fisiologia , Sistemas de Informação Geográfica , Frequência Cardíaca/fisiologia , Corrida/fisiologia , Futebol/fisiologia , Adulto , Humanos , Masculino , Movimento/fisiologia , Estudos de Tempo e MovimentoRESUMO
The aim of this study was to examine the differences in muscle architecture during isometric tests between children and adults. Eight boys (age= 11.2 +/- 0.26 years) and eight men (age= 22.3 +/- 2.01 years) performed plantar flexion isometric efforts at angles of -15 degrees, 0 degrees, 15 degrees at 0%, 40%, 60%, 80% of MVC. Analysis of variance tests indicated that adults showed greater fascicle length from rest to 80% of MVC (p < .05), greater pennation angle at 80% and 100% of MVC (p < .05) and greater aponeuroses displacement at levels of effort greater than 60% of MVC (p < .05). These differences observed in MG would appear to favor better utilization of the force-length and the force-velocity relationships, of the muscle in adults compared with children.
Assuntos
Contração Isométrica/fisiologia , Força Muscular/fisiologia , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/fisiologia , Adolescente , Adulto , Fatores Etários , Análise de Variância , Criança , Humanos , Masculino , Projetos Piloto , Estatística como Assunto , Adulto JovemRESUMO
PURPOSE: The purpose of this study was to examine the efficacy of 8 wk of resistance training to failure versus not to failure training regimens at both moderate and low volumes for increasing upper-body strength and power as well as cardiovascular parameters into a combined resistance and endurance periodized training scheme. METHODS: Forty-three trained male rowers were matched and then randomly assigned to four groups that performed the same endurance training but differed on their resistance training regimen: four exercises leading to repetition failure (4RF; n = 14), four exercises not leading to failure (4NRF; n = 15), two exercises not to failure (2NRF; n = 6), and control group (C; n = 8). One-repetition maximum strength and maximal muscle power output during prone bench pull (BP), average power during a 20-min all-out row test (W 20 min), average row power output eliciting a blood lactate concentration of 4 mmol x L(-1) (W 4 mmol x L(-1)), and power output in 10 maximal strokes (W 10 strokes) were assessed before and after 8 wk of periodized training. RESULTS: 4NRF group experienced larger gains in one- repetition maximum strength and muscle power output (4.6% and 6.4%, respectively) in BP compared with both 4RF (2.1% and j1.2%) and 2NRF (0.6% and -0.6%). 4NRF and 2NRF groups experienced larger gains in W 10 strokes (3.6% and 5%) and in W 20 min (7.6% and 9%) compared with those found after 4RF (-0.1% and 4.6%), whereas no significant differences between groups were observed in the magnitude of changes in W 4 mmol x L(-1) (4NRF = 6.2%, 4RF = 5.3%, 2NRF = 6.8%, and C = 4.5%). CONCLUSIONS: An 8-wk linear periodized concurrent strength and endurance training program using a moderate number of repetitions not to failure (4NRF group) provides a favorable environment for achieving greater enhancements in strength, muscle power, and rowing performance when compared with higher training volumes of repetitions to failure in experienced highly trained rowers.