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Jason D. Vescovi and Devon H. Frayne

Purpose:

To examine locomotor demands and metabolic-power characteristics of National Collegiate Athletic Association (NCAA) field hockey matches.

Methods:

Using a cross-sectional design, global positioning system (GPS) technology tracked Division I field hockey players from 6 teams during 1 regular-season match (68 player observations). An ANOVA compared locomotor demands and metabolic-power characteristics among positions. Paired t tests compared dependent variables between halves.

Results:

Defenders played 5−6 min more than midfielders, whereas midfielders played 6−7 min more than forwards. Defenders covered less relative distance (98 m/min) than forwards and midfielders (110−111 m/min), as well as more low-intensity running than forwards and less high-intensity running than midfielders. Lower mean metabolic power (9.3 W/kg) was observed for defenders than forwards and midfielders (10.4 W/kg). There was no difference in playing time between halves; however, all 3 positions had a reduction in relative distance (7−9%) and mean metabolic power (8−9%) during the second half.

Conclusions:

Despite more playing time, defenders covered less relative distance and had lower mean metabolic power than other positions. Moderate-intensity, high-intensity, and sprint distance were similar between positions, highlighting the greater relative demands on forwards because they tended to have the least amount of playing time. The reduction of key metrics during the second half was similar among positions and warrants further investigation. These initial results can be used to design position-specific drills or create small-sided games that replicate match demands for NCAA athletes, thus helping establish strategies for developing physiological ability of players at this level.

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Tim J. Gabbett

Purpose:

A limitation of most rugby league time–motion studies is that researchers have examined the demands of single teams, with no investigations of all teams in an entire competition. This study investigated the activity profiles and technical and tactical performances of successful and less-successful teams throughout an entire rugby league competition.

Methods:

In total, 185 rugby league players representing 11 teams from a semiprofessional competition participated in this study. Global positioning system analysis was completed across the entire season. Video footage from individual matches was also coded via notational analysis for technical and tactical performance of teams.

Results:

Trivial to small differences were found among Top 4, Middle 4, and Bottom 4 teams for absolute and relative total distances covered and distances covered at low speeds. Small, nonsignificant differences (P = .054, ES = 0.31) were found between groups for the distance covered sprinting, with Top 4 teams covering greater sprinting distances than Bottom 4 teams. Top 4 teams made more meters in attack and conceded fewer meters in defense than Bottom 4 teams. Bottom 4 teams had a greater percentage of slow play-the-balls in defense than Top 4 teams (74.8% ± 7.3% vs 67.2% ± 8.3%). Middle 4 teams showed the greatest reduction in high-speed running from the first to the second half (–20.4%), while Bottom 4 teams completed 14.3% more high-speed running in the second half than in the first half.

Conclusion:

These findings demonstrate that a combination of activity profiles and technical and tactical performance are associated with playing success in semiprofessional rugby league players.

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Jace A. Delaney, Tannath J. Scott, Heidi R. Thornton, Kyle J.M. Bennett, David Gay, Grant M. Duthie and Ben J. Dascombe

Rugby league coaches often prescribe training to replicate the demands of competition. The intensities of running drills are often monitored in comparison with absolute match-play measures. Such measures may not be sensitive enough to detect fluctuations in intensity across a match or to differentiate between positions.

Purpose:

To determine the position- and duration-specific running intensities of rugby league competition, using a moving-average method, for the prescription and monitoring of training.

Methods:

Data from a 15-Hz global positioning system (GPS) were collected from 32 professional rugby league players across a season. The velocity–time curve was analyzed using a rolling-average method, where maximum values were calculated for 10 different durations, 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 min, for each player across each match.

Results:

There were large differences between the 1- and 2-min rolling averages and all other rolling-average durations. Smaller differences were observed for rolling averages of greater duration. Fullbacks maintained a greater velocity than outside backs and middle and edge forwards over the 1- and 2-min rolling averages (ES 0.8−1.2, P < .05). For rolling averages 3 min and greater, the running demands of the fullbacks were greater than those of the middle forwards and outside backs (ES 1.1−1.4, P < .05).

Conclusions:

These findings suggest that the running demands of rugby league fluctuate vastly across a match. Fullbacks were the only position to exhibit a greater running intensity than any other position, and therefore training prescription should reflect this.

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Matthias W. Hoppe, Christian Baumgart, Jutta Bornefeld, Billy Sperlich, Jürgen Freiwald and Hans-Christer Holmberg

The aims of this study were (1) to assess the running activities of adolescent tennis players during match play with respect to velocity, acceleration, and deceleration; (2) to characterize changes in these activities during the course of a match; and (3) to identify potential differences between winners and losers. Twenty well-trained adolescent male athletes (13 ± 1 y) played one simulated match each (giving a total of 10 matches), during which distances covered at different velocity categories (0 to < 1, 1 to < 2, 2 to < 3, 3 to < 4, and ≥ 4 m·s−1) and number of running activities involving high velocity (≥ 3 m·s−1), acceleration (≥ 2 m·s−2), and deceleration (≤ −2 m·s−2) were monitored using a global positioning system (10 Hz). Heart rate was also assessed. The total match time, total distance covered, peak velocity, and mean heart rate were 81.2 ± 14.6 min, 3362 ± 869 m, 4.4 ± 0.8 ms−1, and 159 ± 12 beats min−1, respectively. Running activities involving high acceleration (0.6 ± 0.2 n·min−1) or deceleration (0.6 ± 0.2 n·min−1) were three times as frequent as those involving high velocity (0.2 ± 0.1 n·min−1). No change in the pattern of running activities (P ≥ .13, d ≤ 0.39) and no differences between winners and losers (P ≥ .22, d ≤ 0.53) were evident during match play. We conclude that training of well-trained adolescent male tennis players need not focus on further development of their running abilities, since this physical component of multifactorial tennis performance does not change during the course of a match and does not differ between the winners and losers.

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Jonathan M. Taylor, Tom W. Macpherson, Shaun J. McLaren, Iain Spears and Matthew Weston

Purpose:

To compare the effects of 2 repeated-sprint training programs on fitness in soccer.

Methods:

Fifteen semiprofessional soccer players (age: 24 ± 4 y; body mass: 77 ± 8 kg) completed 6 repeated-sprint training sessions over a 2-week period. Players were assigned to a straight-line (STR) (n = 8; 3–4 sets of 7 × 30 m) or change of direction (CoD) (n = 7; 3–4 sets of 7 × 20-m) repeated-sprint training group. Performance measures included 5-, 10-, and 20-m sprints, countermovement jump, Illinois agility, and Yo-Yo Intermittent Recovery Test level 1 (YYIRTL1) performance. Internal (heart rate) and external (global positioning system-derived measures) training loads were monitored throughout. Data were analyzed using magnitude-based inferences.

Results:

Internal and external loads were higher in the STR group than in the CoD group with large differences in maximum velocity (28.7%; ±90% confidence limits, 3.3%), moderate differences in mean heart rates (7.0%; ±1.4%) and PlayerLoad (17.6%; ±8.6%), and small differences in peak heart rates (3.0%; ±1.6%). Large improvements in 5-m (STR: 9.6%; ±7.0% and CoD: 9.4%; ±3.3%), 10-m (STR: 6.6%; ±4.6% and CoD: 6.7%; ±2.2%), and 20-m (STR: 3.6; ±4.0% and CoD: 4.0; ±1.7%) sprints were observed. Large and moderate improvements in YYIRTL1 performance were observed in the STR (24.0%; ±9.3%) and CoD (31.0%; ±7.5%), respectively. Between-groups differences in outcome measures were unclear.

Conclusions:

Two weeks of repeated-sprint training stimulates improvements in acceleration, speed, and high-intensity running performance in soccer players. Despite STR inducing higher internal and external training loads, training adaptations were unclear between training modes, indicating a need for further research.

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Ric Lovell, Sam Halley, Jason Siegler, Tony Wignell, Aaron J. Coutts and Tim Massard

Purpose: To examine the concurrent and construct validity of numerically blinded ratings of perceived exertion (RPEs). Methods: A total of 30 elite male youth soccer players (age 16.7 [0.5] y) were monitored during training and matches over a 17-wk in-season period. The players’ external loads were determined via raw 10-Hz global positioning system. Heart rate (HR) was collected continuously and expressed as Bannister and Edwards training impulses, and minutes >80% of the players predetermined the maximum HR by the Yo-Yo Intermittent Recovery Test Level 1. RPE was collected confidentially 10 to 15 min after training/matches using 2 methods: (1) a traditional verbal response to the 0 to 100 category-ratio “centiMax” scale (RPE) and (2) numerically blinded RPE centiMax scale (RPEblind) with the response selected manually via a 5 × 7-in tablet “slider.” The RPE and RPEblind were divided by 10 and multiplied by the duration to derive the sessional RPE. Linear mixed models compared ratings, and within-subject repeated-measures correlations assessed the sessional RPE versus HR and external load associations. Results: There were no differences between the RPE and RPEblind (0.19; 95% confidence intervals, −0.59 to 0.20 au, P = .326) or their session values (13.5; 95% confidence intervals, −17.0 to 44.0 au, P = .386), and the ratings were nearly perfectly correlated (r = .96). The associations between the sessional RPE versus HR and external load metrics were large to very large (r = .65–.81), with no differences between the RPE methods (P ≥ .50). The RPEblind also reduced verbal anchor clustering and integer bias by 11% and 50%, respectively. Conclusions: RPEblind demonstrated concurrent and construct validity versus the traditional method, and may be used in situations where practitioners have concerns regarding the authenticity of athlete ratings.

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Liam Anderson, Patrick Orme, Rocco Di Michele, Graeme L. Close, Jordan Milsom, Ryland Morgans, Barry Drust and James P. Morton

Purpose:

To quantify the accumulative training and match load during an annual season in English Premier League soccer players classified as starters (n = 8, started ≥60% of games), fringe players (n = 7, started 30–60% of games) and nonstarters (n = 4, started <30% of games).

Methods

Players were monitored during all training sessions and games completed in the 2013–14 season with load quantified using global positioning system and Prozone technology, respectively.

Results:

When including both training and matches, total duration of activity (10,678 ± 916, 9955 ± 947, 10,136 ± 847 min; P = .50) and distance covered (816.2 ± 92.5, 733.8 ± 99.4, 691.2 ± 71.5 km; P = .16) were not different between starters, fringe players, and nonstarters, respectively. However, starters completed more (all P < .01) distance running at 14.4–19.8 km/h (91.8 ± 16.3 vs 58.0 ± 3.9 km; effect size [ES] = 2.5), high-speed running at 19.9–25.1 km/h (35.0 ± 8.2 vs 18.6 ± 4.3 km; ES = 2.3), and sprinting at >25.2 km/h (11.2 ± 4.2 vs 2.9 ± 1.2 km; ES = 2.3) than nonstarters. In addition, starters also completed more sprinting (P < .01, ES = 2.0) than fringe players, who accumulated 4.5 ± 1.8 km. Such differences in total high-intensity physical work done were reflective of differences in actual game time between playing groups as opposed to differences in high-intensity loading patterns during training sessions.

Conclusions

Unlike total seasonal volume of training (ie, total distance and duration), seasonal high-intensity loading patterns are dependent on players’ match starting status, thereby having potential implications for training program design.

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Jason D. Vescovi and Terence G. Favero

Purpose:

To quantify the locomotor demands of college female soccer matches and compare the relative proportion of distances in specified velocity bands between players completing an entire half with substitutes.

Methods:

College female soccer players (n = 113) were assessed during a regular-season match using global positioning system technology. An ANCOVA was used to compare the locomotor characteristics for positions and substitutes, adjusting for duration played. Paired t tests compared the proportion of distances for players substituted out and back into the second half.

Results:

Defenders covered less total absolute distance than midfielders (first half) and midfielders and forwards (second half) with concomitantly lower work rates. Moderate- and high-intensity running were similar between positions within each half. Midfielders substituted into the match had a lower proportion of moderate-intensity running than those substituted out (15% ± 1.8% vs 19% ± 0.9%), and defenders completing an entire first half had a lower proportion of high-intensity running than defenders substituted in or out (6% ± 1.0% vs 11% ± 1.0% and 16% ± 2.8%). There were no differences in the proportion of distances covered within each velocity band for any position in the second half or for the players substituted out and then back in during the second half.

Conclusions:

The current findings provide novel insight linking the developmental progression between youth and high-level matches for overall demands and work rates. Moderate- and high-intensity distances cumulatively range from 2100 to 2600 m (26–28% total distance) in female college matches. The high amount of consistency observed for the proportions of distance covered suggest that substitution patterns have little impact on locomotor distribution.

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Nicola Furlan, Mark Waldron, Mark Osborne and Adrian J. Gray

Purpose:

To assess the ecological validity of the Rugby Sevens Simulation Protocol (R7SP) and to evaluate its interday reliability.

Methods:

Ten male participants (20 ± 2 y, 74 ± 11 kg) completed 2 trials of the R7SP, separated by 7 d. The R7SP comprised typical running and collision activities, based on data recorded during international rugby sevens match play. Heart rate (HR) was monitored continuously during the R7SP, and the participants’ movements were recorded through a 20-Hz global positioning system unit. Blood lactate and rating of perceived exertion were collected before and immediately after the 1st and 2nd halves of the R7SP.

Results:

The average activity profile was 117 ± 5 m/min, of which 27 ± 2 m/min was covered at high speed, with a calculated energetic demand of 1037 ± 581 J/kg, of which ~40% was expended at a rate above 19 W/kg. Mean HR was 88% ± 4% of maximal HR. Participants spent ~45% ± 27% of time above 90% of maximal HR (t >90%HRmax). There were no significant differences between trials, except for lactate between the halves of the R7SP. The majority of the measured variables demonstrated a between-trials coefficient of variation (CV%) lower than 5%. Blood lactate measurements (14–20% CV) and t >90%HRmax (26% CV) were less reliable variables. In most cases, the calculated moderate worthwhile change was higher than the CV%.

Conclusions:

The R7SP replicates the activity profile and HR responses of rugby sevens match play. It is a reliable simulation protocol that can be used in a research environment to detect systematic worthwhile changes in selected performance variables.

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Dennis-Peter Born, Thomas Stöggl, Mikael Swarén and Glenn Björklund

Purpose:

To investigate the cardiorespiratory and metabolic response of trail running and evaluate whether heart rate (HR) adequately reflects the exercise intensity or if the tissue-saturation index (TSI) could provide a more accurate measure during running in hilly terrain.

Methods:

Seventeen competitive runners (4 women, V̇O2max, 55 ± 6 mL · kg–1 · min–1; 13 men, V̇O2max, 68 ± 6 mL · kg–1 · min–1) performed a time trial on an off-road trail course. The course was made up of 2 laps covering a total distance of 7 km and included 6 steep uphill and downhill sections with an elevation gain of 486 m. All runners were equipped with a portable breath-by-breath gas analyzer, HR belt, global positioning system receiver, and near-infrared spectroscopy (NIRS) device to measure the TSI.

Results:

During the trail run, the exercise intensity in the uphill and downhill sections was 94% ± 2% and 91% ± 3% of maximal heart rate, respectively, and 84% ± 8% and 68% ± 7% of V̇O2max, respectively. The oxygen uptake (V̇O2) increased in the uphill sections and decreased in the downhill sections (P < .01). Although HR was unaffected by the altering slope conditions, the TSI was inversely correlated to the changes in V̇O2 (r = –.70, P < .05).

Conclusions:

HR was unaffected by the continuously changing exercise intensity; however, TSI reflected the alternations in V̇O2. Recently used exclusively for scientific purposes, this NIRS-based variable may offer a more accurate alternative than HR to monitor running intensity in the future, especially for training and competition in hilly terrain.