Search Results

You are looking at 11 - 20 of 102 items for :

Clear All
Restricted access

Laurent B. Seitz, Matt Barr and G. Gregory Haff

Purpose:

To compare the effects of sprint training with or without ball carry on the sprint performance of elite rugby league players.

Methods:

Twenty-four elite rugby league players were divided into a ball-carry group (BC; n = 12) and a no-ball-carry group (NBC; n = 12). The players of the BC group were required to catch and carry the ball under 1 arm during each sprint, whereas the NBC group performed sprints without carrying a ball. The 8-wk training intervention took place during the precompetitive phase of the season and consisted of 2 sessions/wk. Sprint performance was measured before and after the training intervention with 40-m linear sprints performed under 2 conditions: with and without ball carry. Split times of 10, 20, and 40 m were recorded for further analysis. A 3-way (group × time × condition) factorial ANOVA was performed to compare changes in sprint performance with and without the ball, before and after the training intervention for both BC and NBC training groups.

Results:

The BC and NBC groups experienced similar improvements in 10-, 20-, and 40-m sprint times and accelerations, regardless of the condition under which the sprint tests were performed (P = .19).

Conclusions:

Sprint training while carrying a rugby ball is as effective as sprint training without carrying a rugby ball for improving the sprint performance of elite rugby league players.

Restricted access

Gregory Roe, Joshua Darrall-Jones, Christopher Black, William Shaw, Kevin Till and Ben Jones

Purpose:

The purpose of this study was to investigate the validity of timing gates and 10-Hz global positioning systems (GPS) units (Catapult Optimeye S5) against a criterion measure (50-Hz radar gun) for assessing maximum sprint velocity (Vmax).

Methods:

Nine male professional rugby union players performed 3 maximal 40-m sprints with 3 min rest between efforts with Vmax assessed simultaneously via timing gates, 10-Hz GPSOpen (Openfield software), GPSSprint (Sprint software), and radar gun. Eight players wore 3 GPS units, while 1 wore a single unit during each sprint.

Results:

When compared with the radar gun, mean biases for GPSOpen, GPSSprint, and timing gates were trivial, small, and small, respectively. The typical error of the estimate (TEE) was small for timing gate and GPSOpen while moderate for GPSSprint. Correlations with radar gun were nearly perfect for all measures. Mean bias, TEE, and correlations between GPS units were trivial, small, and nearly perfect, respectively, while a small TEE existed when GPSOpenfield was compared with GPSSprint.

Conclusion:

Based on these findings, both 10-Hz GPS and timing gates provide valid measures of 40-m Vmax assessment compared with a radar gun. However, as error did exist between measures, the same testing protocol should be used when assessing 40-m Vmax over time. Furthermore, in light of the above results, it is recommended that when assessing changes in GPS-derived Vmax over time, practitioners should use the same unit for each player and perform the analysis with the same software, preferably Catapult Openfield.

Restricted access

Carl Petersen, David Pyne, Marc Portus and Brian Dawson

Purpose:

The validity and reliability of three commercial global positioning system (GPS) units (MinimaxX, Catapult, Australia; SPI-10, SPI-Pro, GPSports, Australia) were quantified.

Methods:

Twenty trials of cricket-specific locomotion patterns and distances (walking 8800 m, jogging 2400 m, running 1200 m, striding 600 m, sprinting 20- to 40-m intervals, and run-a-three) were compared against criterion measures (400-m athletic track, electronic timing). Validity was quantified with the standard error of the estimate (SEE) and reliability estimated using typical error expressed as a coefficient of variation.

Results:

The validity (mean ± 90% confidence limits) for locomotion patterns walking to striding ranged from 0.4 ± 0.1 to 3.8 ± 1.4%, whereas for sprinting distances over 20 to 40 m including run-a-three (approx. 50 m) the SEE ranged from 2.6 ± 1.0 to 23.8 ± 8.8%. The reliability (expressed as mean [90% confidence limits]) of estimating distance traveled by walking to striding ranged from 0.3 (0.2 to 0.4) to 2.9% (2.3 to 4.0). Similarly, mean reliability of estimating different sprinting distances over 20 to 40 m ranged from 2.0 (1.6 to 2.8) to 30.0% (23.2 to 43.3).

Conclusions:

The accuracy and bias was dependent on the GPS brand employed. Commercially available GPS units have acceptable validity and reliability for estimating longer distances (600–8800 m) in walking to striding, but require further development for shorter cricket-specifc sprinting distances.

Restricted access

Dean G. Higham, David B. Pyne, Judith M. Anson and Anthony Eddy

Although the characteristics of 15-a-side rugby union players have been well defined, there is little information on rugby sevens players.

Purpose:

The authors profiled the anthropometric, physiological, and performance qualities of elite-level rugby sevens players and quantified relationships between these characteristics.

Methods:

Eighteen male international rugby sevens players undertook anthropometric (body mass, height, sum of 7 skinfolds, lean-mass index), acceleration and speed (40-m sprint), muscle-power (vertical jump), repeatedsprint- ability (6 × 30-m sprint), and endurance (Yo-Yo Intermittent Recovery test and treadmill VO2max) testing. Associations between measurements were assessed by correlation analysis.

Results:

Rugby sevens players had anthropometric characteristics (body mass 89.7 ± 7.6 kg, height 1.83 ± 0.06 m, sum of 7 skinfolds 52.2 ± 11.5 mm; mean ± SD) similar to those of backs in international 15-player rugby union. Acceleration and speed (40-m sprint 5.11 ± 0.15 s), muscle-power (vertical jump 66 ± 7 cm), and endurance (VO2max 53.8 ± 3.4 mL · kg−1 · min−1 ) qualities were similar to, or better than, those of professional 15-a-side players. Coefficients of variation ranged from 2.5% to 22%. Relative VO2max was largely correlated with Yo-Yo distance (r = .60, .21−.82; 90% confidence interval) and moderately correlated with 40-m sprint time (r = −.46, −.75 to −.02) and repeated-sprint ability (r = −.38, −.72 to .09).

Conclusions:

International rugby sevens players require highly developed speed, power, and endurance to tolerate the demands of competition. The small between-athletes variability of characteristics in rugby sevens players highlights the need for relatively uniform physical and performance standards in contrast with 15-a-side players.

Restricted access

Paul B. Gastin, Denny Meyer, Emy Huntsman and Jill Cook

Purpose:

To assess the relationships between player characteristics (including age, playing experience, ethnicity, and physical fitness) and in-season injury in elite Australian football.

Design:

Single-cohort, prospective, longitudinal study.

Methods:

Player characteristics (height, body mass, age, experience, ethnicity, playing position), preseason fitness (6-min run, 40-m sprint, 6 × 40-m sprint, vertical jump), and in-season injury data were collected over 4 seasons from 1 professional Australian football club. Data were analyzed for 69 players, for a total of 3879 player rounds and 174 seasons. Injury risk (odds ratio [OR]) and injury severity (matches missed; rate ratio [RR]) were assessed using a series of multilevel univariate and multivariate hierarchical linear models.

Results:

A total of 177 injuries were recorded with 494 matches missed (2.8 ± 3.3 matches/injury). The majority (87%) of injuries affected the lower body, with hamstring (20%) and groin/hip (14%) most prevalent. Nineteen players (28%) suffered recurrent injuries. Injury incidence was increased in players with low body mass (OR = 0.887, P = .005), with poor 6-min-run performance (OR = 0.994, P = .051), and playing as forwards (OR = 2.216, P = .036). Injury severity was increased in players with low body mass (RR = 0.892, P = .008), tall stature (RR = 1.131, P = .002), poor 6-min-run (RR = 0.990, P = .006), and slow 40-m-sprint (RR = 3.963, P = .082) performance.

Conclusions:

The potential to modify intrinsic risk factors is greatest in the preseason period, and improvements in aerobic-running fitness and increased body mass may protect against in-season injury in elite Australian football.

Restricted access

Peter Le Rossignol, Tim J. Gabbett, Dan Comerford and Warren R. Stanton

Purpose:

To investigate the relationship between selected physical capacities and repeated-sprint performance of Australian Football League (AFL) players and to determine which physical capacities contributed to being selected for the first competition game.

Methods:

Sum of skinfolds, 40-m sprint (with 10-, 20-, 30-, and 40-m splits), repeated-sprint ability (6 × 30-m sprints), and 3-km-run time were measured during the preseason in 20 AFL players. The physical qualities of players selected to play the first match of the season and those not selected were compared. Pearson correlation coefficients were used to determine the relationship among variables, and a regression analysis identified variables significantly related to repeated-sprint performance.

Results:

In the regression analysis, maximum velocity was the best predictor of repeated-sprint time, with 3-km-run time also contributing significantly to the predictive model. Sum of skinfolds was significantly correlated with 10-m (r = .61, P < .01) and 30-m (r = .53, P < .05) sprint times. A 2.6% ± 2.1% difference in repeated-sprint time (P < .05, ES = 0.88 ± 0.72) was observed between those selected (25.26 ± 0.55 s) and not selected (25.82 ± 0.80 s) for the first game of the season.

Conclusions:

The findings indicate that maximum-velocity training using intervals of 30–40 m may contribute more to improving repeated-sprint performance in AFL players than short 10- to 20-m intervals from standing starts. Further research is warranted to establish the relative importance of endurance training for improving repeated-sprint performance in AFL football.

Restricted access

Martin Buchheit, Ben M. Simpson, Esa Peltola and Alberto Mendez-Villanueva

The aim of the present study was to locate the fastest 10-m split time (Splitbest) over a 40-m sprint in relation to age and maximal sprint speed in highly trained young soccer players. Analyses were performed on 967 independent player sprints collected in 223 highly trained young football players (Under 12 to Under 18). The maximal sprint speed was defined as the average running speed during Splitbest. The distribution of the distance associated with Splitbest was affected by age (X 2 3 = 158.7, P < .001), with the older the players, the greater the proportion of 30-to-40-m Splitbest. There was, however, no between-group difference when data were adjusted for maximal sprint speed. Maximal sprint speed is the main determinant of the distance associated with Splitbest. Given the important disparity in Splitbest location within each age group, three (U12-U13) to two (U14-U18) 10-m intervals are still required to guarantee an accurate evaluation of maximal sprint speed in young players when using timing gates.

Restricted access

Ari Nummela, James Stray-Gundersen and Heikki Rusko

The purpose of this investigation was to examine the influence of running velocity, stride characteristics, training background, gender, and caliber of a runner on the changes in ground contact time during a 400-m run. Thirteen male and 4 female sprinters ran a 400-m time trial on the track, and 8 male sprinters and 6 male endurance athletes ran a simulated 400-m trial at constant velocity on the treadmill. A special shoe insert was placed in the track spike to determine contact time, and a video camera was used to determine split times for each 40 m. Two threshold points were identified during the 400-m run, with the first occurring when the running velocity began to decrease. The threshold points were affected by the individual running strategy and reflected fatigue-induced changes in the running velocity; they also were independent of gender, training background, and caliber of an athlete.

Restricted access

Geraldine H. Van Gym, Howard A. Wenger and Catherine A. Gaul

This study investigated the effect of engaging in imagery in conjunction with nonspecific training on the transfer of the training to performance. Forty subjects were pretested on a Wingate cycle ergometer test for peak power and a 40-m sprint. Subjects were assigned to one of four groups: imagery training (IT), power training (PT), imagery and power training (DPT), and control (C). Following a 6-week training period, all subjects were retested. Although a MANOVA revealed no significant difference between groups on any variable, the groups-by-time interaction was significant. Therefore an analysis of difference scores on both tests was performed. This analysis revealed that although both the IPT and the PT group significantly improved in peak power, only the IPT group improved significantly on the sprint. The results indicate that imagery coupled with nonspecific training contributes to the enhancement of subsequent performance significantly better than does nonspecific training alone.

Restricted access

Bernard Auvinet, Gilles Berrut, Claude Touzard, Laurent Moutel, Nadine Collet, Denis Chaleil and Eric Barrey

The objective of this study was to measure gait abnormalities in elderly fallers with the Locometrix™ gait-analysis system. This accelerometric device provided the following gait variables: walking speed and stride frequency, length, symmetry, and regularity. The variables were analyzed over a 20-s period of stable walking on a flat track of 40 m. Participants were 20 elderly patients hospitalized for falls (mean age 80.8 ± 5.0 years) and 33 older adults living at home (mean age 77.2 ± 6.5 years). All gait variables were found to be significantly lower in the faller group (p < .05). The lower gait speed, stride length, and stride frequency were previously recognized as nonrelevant in predicting the risk of falling, whereas lower stride symmetry was related to an underlying pathology and lower stride regularity was correlated to the risk of falls. The Locometrix appears to be well suited to measure gait regularity in routine practice.