共查询到20条相似文献,搜索用时 9 毫秒
1.
Ahmun RP Tong RJ Grimshaw PN 《Journal of strength and conditioning research / National Strength & Conditioning Association》2005,19(1):92-97
The benefits of creatine (CR) supplementation are well documented, particularly during repeated bouts of high-intensity muscular activity. Most published experiments use mass-supported (cycle ergometry) activities as a means of evaluating creatine's efficacy, therefore minimizing any possible adverse effects of increased body mass associated with CR supplementation. This study aims to use both mass-supported and mass-dependent activities to assess the effectiveness of acute CR supplementation on a group of highly trained rugby players. A randomized, double-blind, crossover research design was utilized, with subjects receiving 20 g.d(-1) x 5 d of both CR and a glucose placebo (PL). Subjects were assessed via 10 x 6-second Wingate test and a 10 x 40-m sprint test on separate days, presupplementation and postsupplementation. A 28-d washout period separated the two treatments. No significant treatment (p > 0.05) or treatment by test interaction effects (p > 0.05) were observed for peak or minimum power output (W), peak or minimum running velocity (m.s(-1)), or fatigue index (%). No significant differences (p > 0.05) were found postsupplementation for body mass and percentage body fat. Although statistical significance was not achieved for any of the measured parameters, there were small improvements in performance that may be of benefit to rugby players. 相似文献
2.
Davis DS Barnette BJ Kiger JT Mirasola JJ Young SM 《Journal of strength and conditioning research / National Strength & Conditioning Association》2004,18(1):115-120
Strength and conditioning professionals who work with collegiate football players focus much of their time and effort on developing programs to enhance athletic performance. Although there has been much speculation, there is little scientific evidence to suggest which combination of physical characteristics best predicts athletic performance in this population. The purpose of this investigation was to examine the relationship among 6 physical characteristics and 3 functional measures in college football players. Data were gathered on 46 NCAA Division I college football players. The 3 response variables were 36.6-m sprint, 18.3-m shuttle run, and vertical jump. The 6 regressor variables were height, weight, percentage of body fat, hamstring length, bench press, and hang clean. A stepwise multiple regression analysis was performed to screen for variables that predict physical performance. Regression analysis revealed clear prediction models for the 36.6-m sprint and 18.3-m shuttle run. The results of this investigation will help strength and conditioning specialists better understand the variables that predict athletic performance in Division I college football players. 相似文献
3.
Glaister M Lockey RA Abraham CS Staerck A Goodwin JE McInnes G 《Journal of strength and conditioning research / National Strength & Conditioning Association》2006,20(2):273-277
The aim of this study was to examine the effects of short-term creatine monohydrate supplementation on multiple sprint running performance. Using a double-blind research design, 42 physically active men completed a series of 3 indoor multiple sprint running trials (15 x 30 m repeated at 35-second intervals). After the first 2 trials (familiarization and baseline), subjects were matched for fatigue score before being randomly assigned to 5 days of either creatine (4 x d(-1) x 5 g creatine monohydrate + 1 g maltodextrin) or placebo (4 x d(-1) x 6 g maltodextrin) supplementation. Sprint times were recorded via twin-beam photocells, and earlobe blood samples were drawn to evaluate posttest lactate concentrations. Relative to placebo, creatine supplementation resulted in a 0.7 kg increase in body mass (95% likely range: 0.02 to 1.3 kg) and a 0.4% reduction in body fat (95% likely range: -0.2 to 0.9%). There were no significant (p > 0.05) between-group differences in multiple sprint measures of fastest time, mean time, fatigue, or posttest blood lactate concentration. Despite widespread use as an ergogenic aid in sport, the results of this study suggest that creatine monohydrate supplementation conveys no benefit to multiple sprint running performance. 相似文献
4.
Robbins DW Young WB 《Journal of strength and conditioning research / National Strength & Conditioning Association》2012,26(2):388-397
The purpose of this study was to investigate positional relationships between sprint and jump abilities and body mass in elite college American football players (n = 1,136). Data from the annual National Football League combine over the years 2005-2009 were examined. The measures included for examination were the 9.1-, 18.3-, 36.6-, and flying 18.3-m sprints and the vertical and horizontal jumps. Pearson's correlation coefficients (r) were calculated to determine the relationships between the tests, and coefficients of determination (r2) were used to determine common variance. With the exception of the relationship between the 9.1-m and the flying 18.3-m sprints, the relationships between all sprints are very strong. Vertical jump ability is more strongly associated with maximum speed, as compared with acceleration. Horizontal jump ability is similarly associated with maximum speed and acceleration. The 9.1-, 18.3-, and flying 18.3-m sprints and the jump tests would appear to measure independent skills. Stationary start sprints up to 36.6 m appear to be heavily influenced by acceleration and may thus measure similar characteristics. The flying 18.3-m sprint is recommended as a measure of maximum speed. Body mass was most strongly associated with performance in the lineman group. When body mass was controlled for, correlations weakened across all the groups. The role of body mass remains unclear. Regardless of sport, the present research supports the notion that the relationships between various sprint and jump abilities warrant positional consideration. Coaches and practitioners will be able to use the findings of this research to better test and monitor athletes requiring different skills. 相似文献
5.
Glaister M Howatson G Lockey RA Abraham CS Goodwin JE McInnes G 《Journal of strength and conditioning research / National Strength & Conditioning Association》2007,21(3):857-859
The aims of this study were to evaluate the time-course of the familiarization process associated with a test of multiple sprint running performance and to determine the reliability of various performance indices once familiarization had been established. Eleven physically active men (mean age: 21 +/- 2 years) completed 4 multiple sprint running trials (12 x 30 m; repeated at 35-s intervals) with 7 days between trials. All testing was conducted indoors, and times were recorded by twin-beam photocells. Results revealed no apparent learning effects as evidenced by no significant (p > 0.05) between-trial differences in measures of fastest or mean 30-m sprint time. Within-subject test-retest reliability determined over 4 trials by coefficient of variation (CV) and intraclass correlation coefficient (ICC) showed excellent reliability for measures of fastest and mean sprint times (CV range: 1.34-2.24%; ICC range: 0.79-0.94). Pre- and posttrial blood lactate concentrations showed good reliability when judged in context with typical values (CV range: 12.08-18.21%; ICC range: 0.72-0.78). In contrast, and in line with previous research, fatigue data showed much greater variability (CV: 26.43%; ICC: 0.66). The results of this study suggest that high degrees of test-retest reliability can be obtained in many multiple sprint running indices without the need for prior familiarization. 相似文献
6.
Can cycle power predict sprint running performance? 总被引:1,自引:0,他引:1
G J van Ingen Schenau R Jacobs J J de Koning 《European journal of applied physiology and occupational physiology》1991,63(3-4):255-260
A major criticism of present models of the energetics and mechanics of sprint running concerns the application of estimates of parameters which seem to be adapted from measurements of running during actual competitions. This study presents a model which does not perpetuate this solecism. Using data obtained during supra-maximal cycle ergometer tests of highly trained athletes, the kinetics of the anaerobic and aerobic pathways were modelled. Internal power wasted in the acceleration and deceleration of body limbs and the power necessary to overcome air friction was calculated from data in the literature. Assuming a mechanical efficiency as found during submaximal cycling, a power equation was constructed which also included the power necessary to accelerate the body at the start of movement. The differential equation thus obtained was solved through simulation. The model appeared to predict realistic times at 100 m (10.47 s), 200 m (19.63 s) and 400 m (42.99 s) distances. By comparison with other methods it is argued that power equations of locomotion should include the concept of mechanical efficiency. 相似文献
7.
Spinks CD Murphy AJ Spinks WL Lockie RG 《Journal of strength and conditioning research / National Strength & Conditioning Association》2007,21(1):77-85
Acceleration is a significant feature of game-deciding situations in the various codes of football. However little is known about the acceleration characteristics of football players, the effects of acceleration training, or the effectiveness of different training modalities. This study examined the effects of resisted sprint (RS) training (weighted sled towing) on acceleration performance (0-15 m), leg power (countermovement jump [CMJ], 5-bound test [5BT], and 50-cm drop jump [50DJ]), gait (foot contact time, stride length, stride frequency, step length, and flight time), and joint (shoulder, elbow, hip, and knee) kinematics in men (N = 30) currently playing soccer, rugby union, or Australian football. Gait and kinematic measurements were derived from the first and second strides of an acceleration effort. Participants were randomly assigned to 1 of 3 treatment conditions: (a) 8-week sprint training of two 1-h sessions x wk(-1) plus RS training (RS group, n = 10), (b) 8-week nonresisted sprint training program of two 1-h sessions x wk(-1) (NRS group, n = 10), or (c) control (n = 10). The results indicated that an 8-week RS training program (a) significantly improves acceleration and leg power (CMJ and 5BT) performance but is no more effective than an 8-week NRS training program, (b) significantly improves reactive strength (50DJ), and (c) has minimal impact on gait and upper- and lower-body kinematics during acceleration performance compared to an 8-week NRS training program. These findings suggest that RS training will not adversely affect acceleration kinematics and gait. Although apparently no more effective than NRS training, this training modality provides an overload stimulus to acceleration mechanics and recruitment of the hip and knee extensors, resulting in greater application of horizontal power. 相似文献
8.
Hoffman JR Ratamess NA Cooper JJ Kang J Chilakos A Faigenbaum AD 《Journal of strength and conditioning research / National Strength & Conditioning Association》2005,19(4):810-815
The purpose of this study was to explore the effects of 5 weeks of eccentrically loaded and unloaded jump squat training in experienced resistance-trained athletes during the strength/ power phase of a 15-week periodized off-season resistance training program. Forty-seven male college football players were randomly assigned to 1 of 3 groups. One group performed the jump squat exercise using both concentric and eccentric phases of contraction (CE; n = 15). A second group performed the jump squat exercise using the concentric phase only (n = 16), and a third group did not perform the jump squat exercise and served as control (CT; n = 16). No significant differences between the groups were seen in power, vertical jump height, 40-yd sprint speed and agility performance. In addition, no differences between the groups were seen in integrated electromyography activity during the jump squat exercise. Significant differences between the CE and CT groups were seen in Delta 1RM squat (65.8 and 27.5 kg, respectively) and Delta 1RM power clean (25.9 and 3.8 kg, respectively). No other between-group differences were observed. Results of this study provide evidence of the benefits of the jump squat exercise during a short-duration (5-week) training program for eliciting strength and power gains. In addition, the eccentric phase of this ballistic movement appears to have important implications for eliciting these strength gains in college football players during an off-season training program. Thus, coaches incorporating jump squats (using both concentric and eccentric phases of contraction) in the off-season training programs of their athletes can see significant performance improvements during a relatively short duration of training. 相似文献
9.
Brechue WF Mayhew JL 《Journal of strength and conditioning research / National Strength & Conditioning Association》2012,26(2):364-372
The purpose of this study was to assess lower-body muscular strength and work capacity after off-season resistance training and the efficacy of predicting maximal squat strength (1 repetition maximum [1RM]) from repetitions to fatigue. National Collegiate Athletic Association Division-II football players (n = 58) were divided into low-strength (LS, 1RM < 365 lb, n = 32) and high-strength (HS, 1RM ≥ 365 lb, n = 26) groups before training based on median 1RM squat performance. Maximal repetitions to failure (RTFs) were performed with a relative load of 70% of 1RM before training and 60, 70, 80, and 90% of 1RM after 12 weeks of a linear periodization resistance training program. As a team, 1RM squat (32 ± 27 lb), 70% RTF (4.5 ± 4.5 reps), and work capacity at 70% 1RM load (1,482 ± 1,181 lb reps) increased significantly after training. Likewise, training resulted in significant increases in 1RM, RTF at 70% 1RM, and work capacity (load × reps) in both LS (8 ± 33 lb, 3.9 ± 4.7 reps, 1,736 ± 1,521 lb reps, respectively) and HS (27 ± 21 lb, 4.9 ± 4.4 reps, 2,387 ± 1,767 lb reps, respectively), with no significant difference between groups. There was no relationship between the change in work capacity and the change in muscular strength for either the LS (r = 0.02) or HS (r = 0.06) group. Predicted 1RMs were best when RTFs were performed using 80% 1RM (5-17 RTFs), with an error of ±5% in 95% of the subjects. In conclusion, the changes in muscular strength associated with an off-season training program appear to have a positive influence on squat work capacity at 70% of 1RM and allow favorable prediction of 1RM using submaximal loads. 相似文献
10.
Iguchi J Yamada Y Ando S Fujisawa Y Hojo T Nishimura K Kuzuhara K Yuasa Y Ichihashi N 《Journal of strength and conditioning research / National Strength & Conditioning Association》2011,25(12):3368-3377
Iguchi, J, Yamada, Y, Ando, S, Fujisawa, Y, Hojo, T, Nishimura, K, Kuzuhara, K, Yuasa, Y, and Ichihashi, N. Physical and performance characteristics of Japanese division 1 collegiate football players. J Strength Cond Res 25(12): 3368-3377, 2011-This study aimed to establish the physical and performance characteristics of football players in the Japanese Division 1 collegiate football program and perform a comparison of these characteristics between Japanese (n = 208) and US Division 1 football players (n = 797). The following comparisons were made: (a) between a higher-ranked university team vs. a lower-ranked university team in Japan, (b) between different playing positions in Japan, (c) between starters and nonstarters in Japan, and (d) between playing positions in Japan vs. those in the United States. The results of this study suggest that players in the higher-ranked university team were heavier, stronger in back squat, jumped higher, and had greater power than those on the lower-ranked team. Furthermore, linemen were generally characterized by larger size, greater strength, and more fat as compared with backs. On the other hand, backs tended to be faster, smaller in physical size, have higher vertical jump height, and show greater relative strength than linemen did. Starters were taller, heavier, stronger, had more powerful, and more fat-free mass than nonstarters. Finally, our results revealed that players in the United States were superior to players in Japan in all body status comparisons (p < 0.01). This study revealed that performance and superior body composition are essential for the success of a football player. Power and strength seem to be key factors in defining good football performance. 相似文献
11.
12.
Little T Williams AG 《Journal of strength and conditioning research / National Strength & Conditioning Association》2007,21(2):646-648
The purpose of this study was to examine the physiological effects of different sprint repetition protocols on professional footballers. Of particular interest were the abilities of repeated sprint protocols to induce fatigue to an extent observed during competitive soccer. Six professional soccer players were assessed for fatigue rate and physiological responses of heart rate (HR), blood lactate (BLa), and rating of perceived exertion (RPE) during the performance of 4 repeated sprint drills, each totaling a sprint distance of 600 m. The 4 drills used 15- or 40-m sprints with 1:4 or 1:6 exercise: rest ratios. The 15-m sprint drill with 1:4 exercise:rest ratio induced the greatest fatigue (final sprint time 15% greater than initial sprint time) and greatest physiological responses. The 40-m sprint drill using a 1:4 exercise:rest ratio produced similar BLa and HR responses to the 15-m drill (13-14 mmol.L(-1) and 89% HRmax, respectively) but significantly lower RPE (mean +/- SD: 17.1 +/- 0.4 vs. 18.8 +/- 0.4, p < 0.05) and fatigue rates (11.1 vs. 15.0%, p < 0.01). Both sprint distance and exercise:rest ratio independently influenced fatigue rate, with the 15-m sprint distance and the 1:4 exercise:rest ratio inducing significantly (p < 0.01) greater fatigue than the 40-m sprint distance and the 1:6 exercise:rest ratio. The magnitude of fatigue during the 40- x 15-m sprint drill using a 1:6 exercise:rest ratio was 7.5%, which is close to the fatigue rate previously reported during actual soccer play. The present study is the first to examine both variations in sprint distances and rest ratios simultaneously, and the findings may aid the design of repeated sprint training for soccer. 相似文献
13.
Wonwoo Ju Dominic Doran Richard Hawkins Mark Evans Andy Laws Paul S Bradley 《Biology of sport / Institute of Sport》2023,40(1):291
The present study aimed to contextualise physical metrics with tactical actions according to general and specialised tactical roles. A total of 244 English Premier League players were analysed by coding player’s physical-tactical actions via the fusion of tracking data and video. Data were analysed across 5 general (Central Defensive Players = CDP, Wide Defensive Players = WDP, Central Midfield Players = CMP, Wide Offensive Players = WOP, Central Offensive Players = COP) and 11 specialised positions (Centre Backs = CB, Full-Backs = FB, Wing-Backs = WB, Box-to-Box Midfielders = B2BM, Central Defensive Midfielders = CDM, Central Attacking Midfielders = CAM, Wide Midfielders = WM, Wide Forwards = WF, Centre Forwards = CF). COP covered more distance at high-intensity (> 19.8 km · h-1) when performing actions such as ‘Break into Box’, Run in Behind/Penetrate’, and ‘Close Down/Press’ than other positions (ES: 0.6–5.2, P < 0.01). WOP covered more high-intensity ‘Run with Ball’ distance (ES: 0.7–1.7, P < 0.01) whereas WDP performed more ‘Over/Underlap’ distance than other positions (ES: 0.9–1.4, P < 0.01). CDP and WDP covered more high-intensity ‘Covering’ distances than other positions (ES: 0.4–2.4, P < 0.01). Nonetheless, data demonstrated that implementing specialised positional analysis relative to a generalised approach is more sensitive in measuring physical-tactical performances of players with the latter over or underestimating the match demands of the players compared to the former. A contextualised analysis may assist coaches and practitioners when designing position or even player-specific training drills since the data provides unique physical-tactical trends across specialised roles. 相似文献
14.
Nesser TW Huxel KC Tincher JL Okada T 《Journal of strength and conditioning research / National Strength & Conditioning Association》2008,22(6):1750-1754
The purpose of this study was to identify relationships between core stability and various strength and power variables in strength and power athletes. National Collegiate Athletic Association Division I football players (height 184.0 +/- 7.1 cm, weight 100.5 +/- 22.4 kg) completed strength and performance testing before off-season conditioning. Subjects were tested on three strength variables (one-repetition maximum [1RM] bench press, 1RM squat, and 1RM power clean), four performance variables (countermovement vertical jump [CMJ], 20- and 40-yd sprints, and a 10-yd shuttle run), and core stability (back extension, trunk flexion, and left and right bridge). Significant correlations were identified between total core strength and 20-yd sprint (r = -0.594), 40-yd sprint (r = -0.604), shuttle run (r = -0.551), CMJ (r = 0.591), power clean/body weight (BW) (r = 0.622), 1RM squat (r = -0.470), bench press/BW (r = 0.369), and combined 1RM/BW (r = 0.447); trunk flexion and 20-yd sprint (r = -0.485), 40-yd sprint (r = -0.479), shuttle run (r = -0.443), CMJ (r = 0.436), power clean/BW (r = 0.396), and 1RM squat (r = -0.416); back extension and CMJ (r = 0.536), and power clean/BW (r = 0.449); right bridge and 20-yd sprint r = -0.410) and 40-yd sprint (r = -0.435), CMJ (r = 0.403), power clean/BW (r = 0.519) and bench press/BW (r = 0.372) and combined 1RM/BW (r = 0.406); and left bridge and 20-yd sprint (r = -0.376) and 40-yd sprint (r = -0.397), shuttle run (r = -0.374), and power clean/BW (r = 0.460). The results of this study suggest that core stability is moderately related to strength and performance. Thus, increases in core strength are not going to contribute significantly to strength and power and should not be the focus of strength and conditioning. 相似文献
15.
Delecluse C Diels R Goris M 《Journal of strength and conditioning research / National Strength & Conditioning Association》2003,17(3):446-454
This study examined the impact of short-term (7-day), high-dose (0.35 g.kg(-1).d(-1)) oral creatine monohydrate supplementation (CrS) on single sprint running performance (40 m, <6 seconds) and on intermittent sprint performance in highly trained sprinters. Nine subjects completed the double-blind cross-over design with 2 supplementation periods (placebo and creatine) and a 7-week wash-out period. A test protocol consisting of 40-m sprint runs was performed, and running velocity was continuously recorded over the total distance. The maximal sprint performance, the relative degree of fatigue at the end of intermittent sprint exercise (6 x 40 m, 30-second rest interval), as well as the degree of recovery (120-second passive rest) remained unchanged following CrS. There were no significant changes related to CrS in absolute running velocity at any distance between start and finish (40 m). It was concluded that no ergogenic effect on single or repeated 40-m sprint times with varying rest periods was observed in highly trained athletes. 相似文献
16.
Sayers AL Farley RS Fuller DK Jubenville CB Caputo JL 《Journal of strength and conditioning research / National Strength & Conditioning Association》2008,22(5):1416-1421
The purpose of this study was to determine which phase of a 30-m sprint (acceleration and/or maximal velocity) was affected by preperformance static stretching. Data were collected from 20 elite female soccer players. On two nonconsecutive days, participants were randomly assigned to either the stretch or no-stretch condition. On the first day, the athletes in the no-stretch condition completed a standard warm-up protocol and then performed three 30-m sprints, with a 2-minute rest between each sprint. The athletes in the stretch condition performed the standard warm-up protocol, completed a stretching routine of the hamstrings, quadriceps, and calf muscles, and then immediately performed three 30-m sprints, also with a 2-minute rest between each sprint. On the second day, the groups were reversed, and identical procedures were followed. One-way repeated-measures analyses of variance revealed a statistically significant difference in acceleration (p < 0.0167), maximal-velocity sprint time (p < 0.0167), and overall sprint time (p < 0.0167) between the stretch and no-stretch conditions. Static stretching before sprinting resulted in slower times in all three performance variables. These findings provide evidence that static stretching exerts a negative effect on sprint performance and should not be included as part of the preparation routine for physical activity that requires sprinting. 相似文献
17.
Ronnestad BR Kvamme NH Sunde A Raastad T 《Journal of strength and conditioning research / National Strength & Conditioning Association》2008,22(3):773-780
The purpose of this study was to compare the effects of combined strength and plyometric training with strength training alone on power-related measurements in professional soccer players. Subjects in the intervention team were randomly divided into 2 groups. Group ST (n = 6) performed heavy strength training twice a week for 7 weeks in addition to 6 to 8 soccer sessions a week. Group ST+P (n = 8) performed a plyometric training program in addition to the same training as the ST group. The control group (n = 7) performed 6 to 8 soccer sessions a week. Pretests and posttests were 1 repetition maximum (1RM) half squat, countermovement jump (CMJ), squat jump (SJ), 4-bounce test (4BT), peak power in half squat with 20 kg, 35 kg, and 50 kg (PP20, PP35, and PP50, respectively), sprint acceleration, peak sprint velocity, and total time on 40-m sprint. There were no significant differences between the ST+P group and ST group. Thus, the groups were pooled into 1 intervention group. The intervention group significantly improved in all measurements except CMJ, while the control group showed significant improvements only in PP20. There was a significant difference in relative improvement between the intervention group and control group in 1RM half squat, 4BT, and SJ. However, a significant difference between groups was not observed in PP20, PP35, sprint acceleration, peak sprinting velocity, and total time on 40-m sprint. The results suggest that there are no significant performance-enhancing effects of combining strength and plyometric training in professional soccer players concurrently performing 6 to 8 soccer sessions a week compared to strength training alone. However, heavy strength training leads to significant gains in strength and power-related measurements in professional soccer players. 相似文献
18.
Mayhew JL Bird M Cole ML Koch AJ Jacques JA Ware JS Buford BN Fletcher KM 《Journal of strength and conditioning research / National Strength & Conditioning Association》2005,19(3):514-518
The purpose of this study was to determine the relationship of the backward overhead medicine ball (BOMB) throw to power production in college football players. Forty National Collegiate Athletic Association Division II college football players were studied at the end of an 8-week off-season conditioning program for power output determined from a countermovement vertical jump on a force plate and for maximal distance in the standing BOMB throw. Although the reliability of the BOMB test was high (interclass correlation coefficient = 0.86), there was a significant learning effect across 3 trials (p < 0.01). Peak and average powers generated during the vertical jump correlated moderately but significantly with the best BOMB throw distance (r = 0.59 and 0.63, respectively). Considering power relative to body mass or lean body mass failed to produce significant correlations with BOMB throw distance (r = 0.27 and 0.28, respectively). Therefore, the BOMB throw may have limited potential as a predictor of total body explosive power in college football players. 相似文献
19.
Anis Chaalali Khalil Bouriel Mehdi Rouissi Moktar Chtara Bessem Mkaouer John Cronin Anis Chaouachi Karim Chamari 《Biology of sport / Institute of Sport》2022,39(2):379
The purpose of this study was to examine the effects of non-resisted (NRS) and partner-towing resisted (RS) sprint training on legs explosive force, sprint performance and sprint kinematic parameters. Sixteen young elite soccer players (age 16.6 ± 0.2 years, height 175.6 ± 5.7 cm, and body mass 67.6 ± 8.2 kg) were randomly allocated to two training groups: resisted sprint RS (n = 7) and non-resisted sprint NRS (n = 9). The RS group followed a six-week sprint training programme consisting of two “sprint training sessions” per week in addition to their usual soccer training. The NRS group followed a similar sprint training programme, replicating the distances of sprints but without any added resistance. All players were assessed before and after training: vertical and horizontal jumping (countermovement jump (CMJ), squat jump (SJ), and 5-jump test (5JT)), 30 m sprint performance (5, 10, and 20 m split times), and running kinematics (stride length and frequency). In the RS group significant (p < 0.05) changes were: decreased sprint time for 0–5 m, 0–10 m and 0–30 m (-6.31, -5.73 and -2.00%; effect size (ES) = 0.70, 1.00 and 0.41, respectively); higher peak jumping height (4.23% and 3.59%; ES = 0.35 and 0.37, for SJ and CMJ respectively); and 5JT (3.10%; ES = 0.44); and increased stride frequency (3.96%; ES = 0.76). In the NRS group, significant (p < 0.05) changes were: decreased sprint time at 0–30 m (-1.34%, ES = 0.33) and increased stride length (1.21%; ES = 0.17). RS training (partner towing) for six weeks in young soccer players showed more effective performances in sprint, stride frequency and lower-limb explosive force, while NRS training improved sprint performance at 0–30 m and stride length. Consequently, coaches and physical trainers should consider including RS training as part of their sprint training to ensure optimal sprint performance. 相似文献
20.
McCurdy KW Walker JL Langford GA Kutz MR Guerrero JM McMillan J 《Journal of strength and conditioning research / National Strength & Conditioning Association》2010,24(12):3200-3208
The purpose of this study was to determine the relationship between measures of unilateral and bilateral jumping performance and 10- and 25-m sprint performance. Fifteen division I women soccer players (height 165 ± 2.44 cm, mass 61.65 ± 7.7 kg, age 20.19 ± 0.91 years) volunteered to participate in this study. The subjects completed a 10- and 25-m sprint test. The following jump kinematic variables were measured using accelerometry: sprint time, step length, step frequency, jump height and distance, contact time, concentric contact time, and flight time (Inform Sport Training Systems, Victoria, BC, Canada). The following jumps were completed in random order: bilateral countermovement vertical jump, bilateral countermovement horizontal jump, bilateral 40-cm drop vertical jump, bilateral 40-cm drop horizontal jump, unilateral countermovement vertical jump (UCV), unilateral countermovement horizontal jump, unilateral 20-cm drop vertical jump (UDV), and unilateral 20-cm drop horizontal jump (UDH). The trial with the best jump height or distance, reactive strength (jump height or distance/total contact time), and flight time to concentric contact time ratio (FT/CCT) was recorded to analyze the relationship between jump kinematics and sprint performance. None of the bilateral jump kinematics significantly correlated with 10- and 25-m sprint time, step length, or step frequency. Right-leg jump height (r = -0.71, p = 0.006, SEE = 0.152 seconds), FT/CCT (r = -0.58, p = 0.04, SEE = 0.176 seconds), and combined right and left-leg jump height (r = -0.61) were significantly correlated with the 25-m sprint time during the UCV. Right-leg FT/CCT was also significantly related to 25-m step length (r = 0.68, p = 0.03, SEE = 0.06 m) during the UDV. The combined right and left leg jump distance to standing height ratio during the UDH significantly correlated (r = -0.58) with 10-m sprint time. In comparison to bilateral jumps, unilateral jumps produced a stronger relationship with sprint performance. 相似文献