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Mark Waldron, Jamie Highton, Matthew Daniels and Craig Twist

Purpose:

This study aimed to quantify changes in heart rate (HR) and movement speeds in interchanged and whole-match players during 35 elite rugby league performances.

Methods:

Performances were separated into whole match, interchange bout 1, and interchange bout 2 and further subdivided into match quartiles. Mean percentages of peak HR (%HRpeak) and total and high-intensity running (> 14 km/h) meters per minute (m/min) were recorded.

Results:

For whole-match players, a decline in high-intensity m/min and %HRpeak was observed between successive quartiles (P < .05). High-intensity m/min during interchange 1 also progressively declined, although initial m/min was higher than whole match (24.2 ± 7.9 m/min vs 18.3 ± 4.7 m/min, P = .018), and %HRpeak did not change over match quartiles (P > .05). During interchange 2, there was a decline in high-intensity m/min from quartile 1 to quartile 3 (18 ± 4.1 vs 13.4 ± 5 m/min, P = .048) before increasing in quartile 4. Quartiles 1 and 2 also showed an increase in %HRpeak (85.2 ± 6.5 vs 87.3 ± 4.2%, P = .022).

Conclusions:

Replacement players adopted a high initial intensity in their first match quartile before a severe decline thereafter. However, in a second bout, lower exercise intensity at the outset enabled a higher physiological exertion for later periods. These findings inform interchange strategy and conditioning for coaches while also providing preliminary evidence of pacing in team sport.

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Robert N. Singer

To execute flawlessly and automatically in sports competition is the goal of any serious athlete. Automaticity suggests nonconscious attention to the act itself while executing, and not being aware of and therefore vulnerable to external and internal distractors. Self-paced sports and events in sports allow time for preparing to perform in a stable and predictable situation. More recently, cognitive, behavioral, and psychophysiological measures associated with developing and realizing proficiency in such acts have become increasingly identified. Many themes associated with these topics appear in the scholarly literature: conscious vs. nonconscious, controlled vs. automatic, voluntary vs. involuntary, explicit vs. implicit, systematic vs. heuristic, willed vs. nonwilled, aware vs. unaware, internal vs. externally oriented, and intentional vs. unintentional behaviors. Implications are being made about ways to influence the learning process by modeling expertise behaviors, as well as enhancing the performance of elite athletes. Of particular importance is the immediate preperformance and during-performance routine that serves as a mechanism for self-regulation of arousal level, thoughts, performance expectancy, and attentional focus.

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Robert N. Singer

This article explores techniques that individuals can use during learning and performance to influence thoughts, feelings, and subsequent achievement. Of concern is knowing how to learn—how to perform. Learning strategies can be isolated and task-specific, or combinatorial and more generally applied to related tasks. Researchers have primarily labored in the first area, frequently demonstrating the effectiveness of a particular learning strategy in improving the learning of a certain activity. In more recent years the second area, typically defined as metastrategies, is attracting the interest of scholars. Since the notion of metastrategies is vague, they are difficult to define and pose a challenge to investigate as to their influence in learning/performing situations. This article begins with a general discussion about information processing processes involved in attaining movement skill, and the use of strategies and metastrategies. A proposed global strategy, the Five-Step Strategy, is presented that should be useful in the learning/performing of all types of closed (self-paced) athletic acts. The strategies include readying, imaging, focusing, executing, and evaluating. The learning of task-pertinent strategies appears to be particularly influential in a number of ways, ultimately leading to a higher probability of learning efficiency and performance excellence.

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João Ferreira Júnior, Angelo Martini, Diego Borba, Leonardo Gomes, João Pinto, Bernardo Oliveira, Daniel Coelho, Luciano Prado and Luiz Rodrigues

To test if the use of a peaked cap protects children against sun radiation, allowing increased exercise performance, nineteen healthy children (10.3 ± 0.8 years old, 146.2 ± 6.9 cm, 36.8 ± 5.5 kg, 1.2 ± 0.1 m2 and 44.1 ± 2.8 mL.kg-1.min-1) took part in 4 experimental situations: 2 initial familiarization runs and 2 self-paced 6km runs (4 × 1.5 km exercise bouts with 3min rest intervals) one of them wearing a peaked cap (CAP) and another situation without the cap (NOCAP). The CAP and NOCAP situations were randomized. Exercise was performed outdoors 3–7 days apart. Environmental variables were measured every 10min, and physiological variables were measured before and after each run and during the rest intervals. Running velocity did not differ between CAP and NOCAP situations. The mean head temperature was reduced by 1.1 °C in the CAP situation (p < .05). Average skin temperature, mean heart rate, rate of perceived exertion and wet bulb and globe temperature did not differ between CAP and NOCAP. The decrease in the mean head temperature was not sufficient to alter running velocity.

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James Faulkner, Alexis R. Mauger, Brandon Woolley and Danielle Lambrick

Purpose:

To assess the utility of a self-paced maximal oxygen uptake (VO2max) test (SPV) in eliciting an accurate measure of VO2max in comparison with a traditional graded exercise test (GXT) during motorized treadmill exercise.

Design:

This was a cross-sectional experimental study whereby recreationally trained men (n = 13, 25.5 ± 4.6 y) completed 2 maximal exercise tests (SPV, GXT) separated by a 72-h recovery period.

Methods:

The GXT was continuous and incremental, with prescribed 1-km/h increases every 2 min until the attainment of VO2max. The SPV consisted of 5 × 2-min stages of incremental exercise, which were self-selected and adjusted according to 5 prescribed RPE levels (RPE 11, 13, 15, 17, and 20).

Results:

Although no significant differences in VO2max were observed between the SPV and GXT (63.9 ± 3.3 cf 60.9 ± 4.6 mL · kg−1 · min−1, respectively, P > .05), the apparent 4.7% mean difference may be practically important. The 95% limits-of-agreement analysis was 3.03 ± 11.49 mL · kg−1 · min−1. Therefore, in the worst-case scenario, the GXT may underestimate measured VO2max as ascertained by the SPV by up to 19%. Conversely, the SPV could underestimate the GXT by 14%.

Conclusions:

The current study has shown that the SPV is an accurate measure of VO2max during exercise on a motorized treadmill and may provide a slightly higher VO2max value than that obtained from a traditional GXT. The higher VO2max during the SPV may be important when prescribing training or monitoring athlete progression.

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Rich D. Johnston, Tim J. Gabbett, Anthony J. Seibold and David G. Jenkins

Purpose:

Repeated sprinting incorporating tackles leads to greater reductions in sprint performance than repeated sprinting alone. However, the influence of physical contact on the running demands of game-based activities is unknown. The aim of this study was to determine whether the addition of physical contact altered pacing strategies during game-based activities.

Methods:

Twenty-three elite youth rugby league players were divided into 2 groups. Group 1 played the contact game on day 1 while group 2 played the noncontact game; 72 h later they played the alternate game. Each game consisted of offside touch on a 30 × 70-m field, played over two 8-min halves. Rules were identical between games except the contact game included a 10-s wrestle bout every 50 s. Microtechnology devices were used to analyze player movements.

Results:

There were greater average reductions during the contact game for distance (25%, 38 m/min, vs 10%, 20 m/min; effect size [ES] = 1.78 ± 1.02) and low-speed distance (21%, 24 m/min, vs 0%, 2 m/s; ES = 1.38 ± 1.02) compared with the noncontact game. There were similar reductions in high-speed running (41%, 18 m/min, vs 45%, 15 m/min; ES = 0.15 ± 0.95).

Conclusions:

The addition of contact to game-based activities causes players to reduce low-speed activity in an attempt to maintain high-intensity activities. Despite this, players were unable to maintain high-speed running while performing contact efforts. Improving a player’s ability to perform contact efforts while maintaining running performance should be a focus in rugby league training.

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Andrew Renfree and Alan St Clair Gibson

Purpose:

To analyze pacing strategies displayed by athletes achieving differing levels of performance during an elite-level marathon race.

Methods:

Competitors in the 2009 IAAF Women’s Marathon Championship were split into groups 1, 2, 3, and 4 comprising the first, second, third, and fourth 25% of finishers, respectively. Final, intermediate, and personal-best (PB) times of finishers were converted to mean speeds, and relative speed (% of PB speed) was calculated for intermediate segments.

Results:

Mean PB speed decreased from groups 1 to 4, and speeds maintained in the race were 98.5% ± 1.8%, 97.4% ± 3.2%, 95.0% ± 3.1%, and 92.4% ± 4.4% of PB speed for groups 1–4 respectively. Group 1 was fastest in all segments, and differences in speed between groups increased throughout the race. Group 1 ran at lower relative speeds than other groups for the first two 5-km segments but higher relative speeds after 35 km. Significant differences (P < .01) in the percentage of PB speed maintained were observed between groups 1 and 4 and groups 2 and 4 in all segments after 20 km and groups 3 and 4 from 20 to 25 km and 30 to 35 km.

Conclusions:

Group 1 athletes achieved better finishing times relative to their PB than athletes in other groups, who selected unsustainable initial speeds resulting in subsequent significant losses of speed. It is suggested that psychological factors specific to a major competitive event influenced decision making by athletes, and poor decisions resulted in final performances inferior to those expected based on PB times.

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Thomas Muehlbauer, Christian Schindler and Stefan Panzer

Purpose:

This study assessed the effect of time spent in several race sectors (S) on finishing time and determined the variance in distribution of skating time and in total race time for official 1000-m sprint races conducted during a competitive season.

Methods:

Total race and sector times for the first 200 m (S1) and the following two 400-m laps (S2 and S3) of 34 female and 31 male elite speed skaters performed during a series of World Cup Meetings were analyzed.

Results:

Overall, skaters started fast, reached their peak in S2, and slowed down in S3, irrespective of race category considered (eg, rank of athlete, number of race, altitude of rink, starting lane). Regression analyses revealed that spending a shorter fraction of time in the last (women in S3: B = 239.1; P < .0001; men in S3: B = 201.5; P < .0001) but not in the first (women in S1: B = -313.1; P < .0001; men in S1: B = -345.6; P < .0001) race sector is associated with a short total race time. Upper- compared with lower-ranked skaters varied less in competition-to-competition sector and total race times (women: 0.02 to 0.33 vs 0.02 to 0.51; men: 0.01 to 0.15 vs 0.02 to 0.57).

Conclusion:

This study confirmed that skaters adopted a fast start pacing strategy during official 1000-m sprint races. However, analyses indicate that shortening time in the closing but not in the starting sector is beneficial for finishing fast. In addition, findings suggest that lower-ranked skaters should concentrate training on lowering their competition-to-competition variability in sector times.

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Candice Martin, Benita Olivier and Natalie Benjamin

Context:

The Functional Movement Screen (FMS) has been found to be a valid preparticipation screening tool in the prediction of injury among various athletes in different sports. The validity thereof in the prediction of injury among adolescent cricketers is yet to be established.

Objective:

To determine if a preseason FMS total score is a valid predictor of in-season injury among adolescent pace bowlers.

Design:

Prospective observational quantitative study.

Setting:

Bowlers performed the FMS before the start of the season. Injury incidence was monitored monthly throughout the season. The student t test and Fisher’s exact test were used to compare the FMS scores of the injured and noninjured bowlers as well as the injured and noninjured bowlers who scored ≤ 14.

Participants:

27 injury-free, male, adolescent pace bowlers.

Main Outcome Measures:

The FMS (scoring criteria and score sheet) and standardized self-administered injury questionnaire.

Results:

There was no difference between the noninjured group (16.55 ± 2.57) and the injured (16.1 ± 2.07) group in terms of FMS scores. There was no significant difference between injured and noninjured bowlers who scored ≤ 14. A total FMS score of 14 does not provide the sensitivity needed to assess injury risk among adolescent pace bowlers and no other accurate cut-off score could be calculated.

Conclusion:

Preseason observed total FMS score is a poor predictor of in-season injury among adolescent pace bowlers. Further research should be conducted to determine if a specific FMS test will be a more valid predictor of injury.

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Christopher R. D. Wagstaff

This study used a single-blind, within-participant, counterbalanced, repeated-measures design to examine the relationship between emotional self-regulation and sport performance. Twenty competitive athletes completed four laboratory-based conditions; familiarization, control, emotion suppression, and nonsuppression. In each condition participants completed a 10-km cycling time trial requiring self-regulation. In the experimental conditions participants watched an upsetting video before performing the cycle task. When participants suppressed their emotional reactions to the video (suppression condition) they completed the cycling task slower, generated lower mean power outputs, and reached a lower maximum heart rate and perceived greater physical exertion than when they were given no self-regulation instructions during the video (nonsuppression condition) and received no video treatment (control condition). The findings suggest that emotional self-regulation resource impairment affects perceived exertion, pacing and sport performance and extends previous research examining the regulation of persistence on physical tasks. The results are discussed in line with relevant psychophysiological theories of self-regulation and fatigue and pertinent potential implications for practice regarding performance and well-being are suggested.