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Giulia De Ioannon, Giuseppe Cibelli, Sergio Mignardi, Agnese Antonelli, Laura Capranica and Maria Francesca Piacentini

Purpose:

To evaluate the pacing strategy, rating of perceived exertion (RPE), and mood during a 78.1-km solo ultraendurance open-water swim.

Methods:

Before and after the event, anthropometric parameters, cortisol, and the profile of mood state (POMS) of 1 male athlete (age 48 y, height 172 cm, body mass 68 kg, body fat 7.2%, athletic achievement: Italian record holder of the Channel Swim) were ascertained. Every 3 h during the event, average swimming speed (SS), stroke rate, stroke length (SL), and RPE were recorded.

Results:

The athlete completed the event in 23:44 h:min. Compared with the first 3 h of swimming, decreases in SS (−33%) and SL (−25%) were observed between 18 h and 21 h. Thereafter, the athlete increased SS (+41%) and SL (+17%) between 21 h and the end. RPE steadily increased from the beginning to the last 6 h of swimming. Cortisol showed a 23-fold increase. After the event, POMS showed a 500% increase in fatigue, 44% decrease in tension, and 77% decrease in vigor.

Conclusion:

For the first time ever an athlete crossed the Adriatic Sea. This case study shows that the athlete adopted a variable pacing strategy to complete 78 km. Despite the athlete perceiving his effort at maximum during the last 6 h, the observed increases in SS at the end of the event might substantiate his high potential motivation to accomplish this challenging and unique event.

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Jamie Highton, Thomas Mullen and Craig Twist

Purpose:

To examine the influence of knowledge of exercise duration on pacing and performance during simulated rugby league match play.

Methods:

Thirteen male university rugby players completed 3 simulated rugby league matches (RLMSP-i) on separate days in a random order. In a control trial, participants were informed that they would be performing 2 × 23-min bouts (separated by 20 min) of the RLMSP-i (CON). In a second trial, participants were informed that they would be performing 1 × 23-min bout of the protocol but were then asked to perform another 23-min bout (DEC). In a third trial, participants were not informed of the exercise duration and performed 2 × 23-min bouts (UN).

Results:

Distance covered and high-intensity running were higher in CON (4813 ± 167 m, 26 ± 4.1 m/min) than DEC (4764 ± 112 m, 25.2 ± 2.8 m/min) and UN (4744 ± 131 m, 24.4 m/min). Compared with CON, high-intensity running and peak speed were typically higher for DEC in bout 1 and lower in bout 2 of the RLMSP-i, while UN was generally lower throughout. Similarly, DEC resulted in an increased heart rate, blood lactate, and rating of perceived exertion than CON in bout 1, whereas these variables were lower throughout the protocol in UN.

Conclusions:

Pacing and performance during simulated rugby league match play depend on an accurate understanding of the exercise endpoint. Applied practitioners should consider informing players of their likely exercise duration to maximize running.

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Michael W. Beets and Kenneth H. Pitetti

Background:

To examine the Healthy Fitness Zone (pass/fail) criterion-referenced reliability (CRR) and equivalency (CRE) of the 1-mile run/walk (MRW) and Progressive Aerobic Cardiovascular Endurance Run (PACER) in adolescents (13 to 18 years).

Methods:

Seventy-six girls and 165 boys were randomly assigned to complete 2 trials of each test.

Results:

CRR for the boys on the MRW (Pa = 77%, κq = 0.53) was lower than on the PACER (Pa = 81%, κq = 0.63); girls were classified more similarly on the MRW (Pa = 83%, κq = 0.67) than on the PACER (Pa = 79%, κq = 0.58). The CRE between the MRW and PACER indicated boys (Pa = 77%, κq = 0.55) were classified more consistently on both tests than girls (Pa = 73%, κq = 0.46).

Conclusions:

No test provided greater consistency. Practitioners may consider other features, such as ease of administration, environmental conditions, and comparative use in the literature.

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Yann Le Meur, Thierry Bernard, Sylvain Dorel, Chris R. Abbiss, Gérard Honnorat, Jeanick Brisswalter and Christophe Hausswirth

Purpose:

The purpose of the present study was to examine relationships between athlete’s pacing strategies and running performance during an international triathlon competition.

Methods:

Running split times for each of the 107 finishers of the 2009 European Triathlon Championships (42 females and 65 males) were determined with the use of a digital synchronized video analysis system. Five cameras were placed at various positions of the running circuit (4 laps of 2.42 km). Running speed and an index of running speed variability (IRSVrace) were subsequently calculated over each section or running split.

Results:

Mean running speed over the frst 1272 m of lap 1 was 0.76 km-h–1 (+4.4%) and 1.00 km-h–1 (+5.6%) faster than the mean running speed over the same section during the three last laps, for females and males, respectively (P < .001). A significant inverse correlation was observed between RSrace and IRSVrace for all triathletes (females r = -0.41, P = .009; males r = -0.65, P = .002; and whole population -0.76, P = .001). Females demonstrated higher IRSVrace compared with men (6.1 ± 0.5 km-h–1 and 4.0 ± 1.4 km-h–1, for females and males, respectively, P = .001) due to greater decrease in running speed over uphill sections.

Conclusions:

Pacing during the run appears to play a key role in high-level triathlon performance. Elite triathletes should reduce their initial running speed during international competitions, even if high levels of motivation and direct opponents lead them to adopt an aggressive strategy.

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Olaf S. Noorbergen, Marco J. Konings, Dominic Micklewright, Marije T. Elferink-Gemser and Florentina J. Hettinga

Purpose:

To explore pacing behavior and tactical positioning during the shorter 500- and 1000-m short-track competitions.

Methods:

Lap times and intermediate rankings of elite 500- and 1000-m short-track-skating competitors were collected over the 2012–13 season. First, lap times were analyzed using a MANOVA, and for each lap, differences between sex, race type, final ranking, and stage of competition were determined. Second, Kendall tau-b correlations were used to assess relationships between intermediate and final rankings. In addition, intermediate rankings of the winner of each race were examined.

Results:

Top-placed athletes appeared faster than bottom-placed athletes in every lap in the 500-m, while in the 1000-m no differences were found until the final 4 laps (P < .05). Correlations between intermediate and final rankings were already high at the beginning stages of the 50-m (lap 1: r = .59) but not for the 1000-m (lap 1: r = .21).

Conclusions:

Although 500- and 1000-m short-track races are both relatively short, fundamental differences in pacing behavior and tactical positioning were found. A fast-start strategy seems to be optimal for 500-m races, while the crucial segment in 1000-m races seems to be from the 6th lap to the finish line (ie, after ± 650 m). These findings provide evidence to suggest that athletes balance between choosing an energetically optimal profile and the tactical and positional benefits that play a role when riding against an opponent, as well as contributing to developing novel insights in exploring athletic behavior when racing against opponents.

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Marco J. Konings, Olaf S. Noorbergen, David Parry and Florentina J. Hettinga

Purpose:

To gain more insight in pacing behavior and tactical positioning in 1500-m short-track speed skating, a sport in which several athletes directly compete in the same race.

Methods:

Lap times and intermediate rankings of elite 1500-m short-track-skating competitors were collected over the season 2012–13 (N = 510, 85 races). Two statistical approaches were used to assess pacing behavior and tactical positioning. First, lap times were analyzed using a MANOVA, and for each lap differences between sex, race type, final rankings, and stage of competition were determined. Second, Kendall tau b correlations were used to assess relationships between intermediate and final rankings. In addition, intermediate rankings of the winner of each race were examined.

Results:

In 1500 m (13.5 laps of 111.12 m), correlations between intermediate and final ranking gradually increased throughout the race (eg, lap 1, r = .05; lap 7, r = .26; lap 13, r = .85). Moreover, the percentage of race winners skating in the leading position was over 50% during the last 3 laps. Top finishers were faster than bottom-place finishers only during the last 5 laps, with on average 0.1- to 1.5-s faster lap times of the race winners compared with the others during the last 5 laps.

Conclusions:

Although a fast start led to faster finishing times, top finishers were faster than bottom-placed finishers only during the last 5 laps. Moreover, tactical positioning at 1 of the foremost positions during the latter phase of the race appeared to be a strong determinant of finishing position.

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Jacob Cohen, Bridgette Reiner, Carl Foster, Jos J. de Koning, Glenn Wright, Scott T. Doberstein and John P. Porcari

The rating of perceived exertion (RPE) normally grows as a scalar function of relative competitive distance, suggesting that it may translate between the brain and body relative to managing fatigue during time-trial exercise. In nonstandard pacing situations, a reciprocal relationship between RPE and power output (PO) would be predicted.

Purpose:

To determine whether PO would decrease when RPE was forced above the normal growth curve during a cycle time trial.

Methods:

Well-trained cyclists performed randomly ordered 10-km cycle time trials. In CONTROL they rode at their own best pace throughout. In BURST, they made a 1-km “burst” at the 4-km mark and then finished as rapidly as possible.

Results:

CONTROL was significantly (P < .05) faster than BURST (16:36 vs 17:00 min). During CONTROL, responses between 4 and 5 km were PO, 240 W; RPE, 5–6; and blood lactate [HLa], 8–9 mmol/L. During BURST PO increased to 282 W, then fell to 220 W after the burst and remained below CONTROL until the end spurt (9 km). RPE increased to 9 during the burst but returned to the normal RPE growth pattern by 6 km; [HLa] increased to ~13 mmol/L after the burst and remained elevated throughout the remainder of the trial.

Conclusions:

The reciprocal behavior of RPE and PO after BURST supports the hypothesis that RPE translates between the brain and the body during heavy exercise. However, the continuing reduction of PO after the burst, even after RPE returned to its normal growth pattern, suggests that PO is regulated in a more complex manner than reflected solely by RPE.

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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.

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Florentina J. Hettinga

was on the topic of racing and pacing. 2 – 4 As a young academic, academic “racing” and also pacing is something an emerging scientist, researcher, and academic needs to learn: how to achieve optimal results, how to plan activities and effort distribution, how to deal with different competitive

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Matthew T. Mahar, Gregory J. Welk, David A. Rowe, Dana J. Crotts and Kerry L. McIver

Background:

The purpose of this study was to develop and cross-validate a regression model to estimate VO2peak from PACER performance in 12- to 14-year-old males and females.

Methods:

A sample of 135 participants had VO2peak measured during a maximal treadmill test and completed the PACER 20-m shuttle run. The sample was randomly split into validation (n = 90) and cross-validation (n = 45) samples. The validation sample was used to develop the regression equation to estimate VO2peak from PACER laps, gender, and body mass.

Results:

The multiple correlation (R) was .66 and standard error of estimate (SEE) was 6.38 ml·kg−1·min−1. Accuracy of the model was confirmed on the cross-validation sample. The regression equation developed on the total sample was: VO2peak = 47.438 + (PACER*0.142) + (Gender[m=1, f=0]*5.134) − (body mass [kg]*0.197), R = .65, SEE = 6.38 ml·kg–1·min–1.

Conclusions:

The model developed in this study was more accurate than the Leger et al. model and allows easy conversion of PACER laps to VO2peak.