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Kristy Martin, Disa Smee, Kevin G. Thompson and Ben Rattray

Purpose:

Nitrate supplementation improves endurance exercise and single bouts of high-intensity activity, but its effect on repeated sprints is unclear. This study is the first to investigate the effects of acute dietary nitrate supplementation during a high-intensity intermittent-sprint test to exhaustion.

Methods:

Team-sport athletes (9 male, age 22.3 ± 2.1 y, VO2max 57.4 ± 8.5 mL · kg−1 · min−1; 7 female, age 20.7 ± 1.3 y, VO2max 47.2 ± 8.5 mL · kg−1 · min−1) were assigned to a double-blind, randomized, crossover design. Participants consumed 70 mL of concentrated beetroot juice containing a minimum of 0.3 g of nitrate (NT) or 70 mL of placebo (PL) 2 h before a repeated-sprint protocol involving repeated 8-s sprints with 30-s recovery on a cycle ergometer to exhaustion.

Results:

Fewer sprints (NT = 13 ± 5 vs PL = 15 ± 6, P = .005, d = 0.41) and less total work (NT = 49.2 ± 24.2 kJ vs PL = 57.8 ± 34.0 kJ, P = .027, d = 0.3) were completed in NT relative to PL. However there was no difference in overall mean power output or the mean power output for each individual 8-s sprint.

Conclusions:

These findings suggest that dietary nitrate is not beneficial for improving repeated-sprint performance, at least when such sprints are near-maximal and frequent in nature. The lack of an effect of nitrate at near-maximal oxygen uptake supports the suggestion that at greater exercise intensities nitrate does not have an ergogenic effect.

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Elizabeth L. Abbey and Janet Walberg Rankin

Maintenance of repeated-sprint performance is a goal during team-sport competition such as soccer. Quercetin has been shown to be an adenosine-receptor antagonist and may reduce oxidative stress via inhibition of the enzyme xanthine oxidase (XO). The purpose of the study was to determine the effect of quercetin consumption on performance of repeated sprints and, secondarily, the XO and inflammatory-marker response induced by repeated-sprint exercise. Fifteen recreationally active, young adult men completed 2 repeated-sprint tests (RST), 12 × 30-m maximal-effort sprints (S1–S12), each after 1 wk supplementation with a placebo, a 6% carbohydrate commercial sports drink, or that drink with 500 mg of quercetin-3-glucoside, consumed twice a day (1,000 mg/d). Blood samples were collected before supplementation (B0), at baseline before each RST (B1), immediately after RST (B2), and 1 hr after RST (B3). Mean sprint time increased progressively and was significantly higher by S9 for both treatments (5.9%); however, there were no significant differences between treatments. Percent fatigue decrement (%FD) for placebo (3.8% ± 2.3%) was significantly less than with quercetin (5.1% ± 2.7%). Changes in blood XO, IL-6, and uric acid from B1 to B2 were +47%, +77%, and +25%, respectively, with no difference by treatment. In conclusion, repeated-sprint performance was not improved by quercetin supplementation and was worse than with placebo when expressed as %FD. Quercetin did not attenuate indicators of XO activity or IL-6, a marker of the inflammatory response after sprint exercise.

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Ken Hodge and Wayne Smith

This case study focused on pressure, stereotype threat, choking, and the coping experiences of the New Zealand All Blacks rugby team during the period from 2004-2011 leading into their success at the 2011 Rugby World Cup (RWC). Employing a narrative approach this case study examined public expectation, pressure, and coach-led coping strategies designed to “avoid the choke” by the All Blacks team. An in-depth interview was completed with one of the All Blacks’ coaches and analyzed via collaborative thematic analysis (Riessman, 2008). In addition multiple secondary data sources (e.g., coach & player autobiographies; media interviews) were analyzed via holistic-content analysis (Lieblich et al., 1998). Collectively these analyses revealed five key themes: public expectation and pressure, learning from 2007 RWC, coping with RWC pressure, decision-making under pressure, and avoiding the choke. Practical recommendations are offered for team sport coaches with respect to coping with pressure and avoiding choking.

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Aaron T. Scanlan, Neal Wen, Joshua H. Guy, Nathan Elsworthy, Michele Lastella, David B. Pyne, Daniele Conte and Vincent J. Dalbo

are yet to be explored in basketball players, with research on this topic only encompassing collegiate team sport athletes. 10 , 11 Nevertheless, existing data are promising, showing strong relationships between impulse at 100 and 300 ms and 5-m linear sprint time ( r  = −.71 to −.74) 11 as well as

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Stephen Harvey, John William Baird Lyle and Bob Muir

A defining element of coaching expertise is characterised by the coach’s ability to make decisions. Recent literature has explored the potential of Naturalistic Decision Making (NDM) as a useful framework for research into coaches’ in situ decision making behaviour. The purpose of this paper was to investigate whether the NDM paradigm offered a valid mechanism for exploring three high performance coaches’ decision-making behaviour in competition and training settings. The approach comprised three phases: 1) existing literature was synthesised to develop a conceptual framework of decision-making cues to guide and shape the exploration of empirical data; 2) data were generated from stimulated recall procedures to populate the framework; 3) existing theory was combined with empirical evidence to generate a set of concepts that offer explanations for the coaches’ decision-making behaviour. Findings revealed that NDM offered a suitable framework to apply to coaches’ decision-making behaviour. This behaviour was guided by the emergence of a slow, interactive script that evolves through a process of pattern recognition and/or problem framing. This revealed ‘key attractors’ that formed the initial catalyst and the potential necessity for the coach to make a decision through the breaching of a ‘threshold’. These were the critical factors for coaches’ interventions.

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Jo Batey and Helen Owton

Maintaining involvement in sport and exercise activities is a challenge for mothers with young children. This study therefore qualitatively explores the experiences of 7 mothers who have managed to remain physically active in team sports exploring how the team environment might meet their psychological needs. We analyze the results through Self-Determination Theory (SDT). Semistructured interviews were thematically analyzed to reveal the following themes: perceived benefits of sport, perceived benefits of being part of a team, needing time out from being a mother, social support and empowerment and self-determination. Feelings of competence, autonomy and relatedness were interwoven to these themes thus demonstrating the applicability of SDT to this domain.

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Frankie Tan, Ted Polglaze, Gregory Cox, Brian Dawson, Iñigo Mujika and Sally Clark

This study investigated the effects of sodium bicarbonate (NaHCO3) ingestion on simulated water polo match performance. Twelve elite players from the Australian National Women’s Water Polo Squad (age 23.7 ± 3.0 yr, height 1.73 ± 0.05 m, body mass 75.7 ± 8.0 kg) participated in the study. In a randomized cross-over double-blind design, players ingested 0.3 g/kg of NaHCO3 or placebo 90 min before performing a 59-min match-simulation test (MST) that included 56 × 10-m maximal-sprint swims as the performance measure. Capillary blood samples were obtained preingestion, pre- and post-warm-up, and after each quarter of the MST. Preexercise ingestion of NaHCO3 was effective in enhancing extracellular pH from baseline levels of 7.41; ±0.01 (M; ±90% confidence limits) to 7.49; ±0.01 and bicarbonate levels from 24.4; ±0.3 to 28.5; ±0.5 mmol/L. The percentage difference in mean sprint times between trials showed no substantial effects of NaHCO3 (0.4; ±1.0, effect size = 0.09; ±0.23; p = .51). These findings are contrary to those of previous NaHCO3 studies on simulated team-sport performance, but this investigation is unique in that it examined highly trained athletes performing sport-specific tasks. In conclusion, water polo players should not expect substantial enhancement in intermittent-sprint performance from NaHCO3 supplementation.

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Benita J. Lalor, Shona L. Halson, Jacqueline Tran, Justin G. Kemp and Stuart J. Cormack

Australian Football (AF) is an intermittent team sport involving rapid accelerations and decelerations, collisions, and large distances covered at a high intensity. 1 The competitive season can produce high levels of fatigue, and optimizing recovery in order to maximize performance is critical. 1

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Luka Svilar, Julen Castellano, Igor Jukic and David Casamichana

this variable is in the second component. This is in line with the profile in activity demands in a multidirectional team sport, such as basketball, where the number of activity changes can range between 997 and 2733 per game. 21 For centers and guards, the hJUMP external load variable was also the

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Tim J. Gabbett, Ben Walker and Shane Walker

Purpose:

To investigate the influence of prior knowledge of exercise duration on the pacing strategies employed during gamebased activities.

Methods:

Twelve semiprofessional team-sport athletes (mean ± SD age 22.8 ± 2.1 y) participated in this study. Players performed 3 small-sided games in random order. In one condition (Control), players were informed that they would play the small-sided game for 12 min and then completed the 12-min game. In a 2nd condition (Deception), players were told that they would play the small-sided game for 6 minutes, but after completing the 6-min game, they were asked to complete another 6 min. In a 3rd condition (Unknown), players were not told how long they would be required to play the small-sided game, but the activity was terminated after 12 min. Movement was recorded using a GPS unit sampling at 10 Hz. Post hoc inspection of video footage was undertaken to count the number of possessions and the number and quality of disposals.

Results:

Higher initial intensities were observed in the Deception (130.6 ± 3.3 m/min) and Unknown (129.3 ± 2.4 m/min) conditions than the Control condition (123.3 ± 3.4 m/min). Greater amounts of high-speed running occurred during the initial phases of the Deception condition, and more low-speed activity occurred during the Unknown condition. A moderately greater number of total skill involvements occurred in the Unknown condition than the Control condition.

Conclusions:

These findings suggest that during game-based activities, players alter their pacing strategy based on the anticipated endpoint of the exercise bout.