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Stephen J. Bailey, Anni Vanhatalo, Matthew I. Black, Fred J. DiMenna and Andrew M. Jones

Purpose:

To assess whether combining prior “priming” exercise with an all-out pacing strategy is more effective at improving oxygen-uptake (V̇O2) kinetics and cycling performance than either intervention administered independently.

Methods:

Nine men completed target-work cycling performance trials using a self-paced or all-out pacing strategy with or without prior severe-intensity (70%Δ) priming exercise. Breath-by-breath pulmonary V̇O2 and cycling power output were measured during all trials.

Results:

Compared with the self-paced unprimed control trial (22 ± 5 s), the V̇O2 mean response time (MRT) was shorter (V̇O2 kinetics were faster) with all-out pacing (17 ± 4 s) and priming (17 ± 3 s), with the lowest V̇O2 MRT observed when all-out pacing and priming were combined (15 ± 4 s) (P < .05). However, total O2 consumed and end-exercise V̇O2 were only higher than the control condition in the primed trials (P < .05). Similarly, cycling performance was improved compared with control (98 ± 11 s) in the self-paced primed (93 ± 8 s) and all-out primed (92 ± 8 s) trials (P < .05) but not the all-out unprimed trial (97 ± 5 s; P > .05).

Conclusions:

These findings suggest that combining an all-out start with severe-intensity priming exercise additively improves V̇O2 MRT but not total O2 consumption and cycling performance since these were improved by a similar magnitude in both primed trials relative to the self-paced unprimed control condition. Therefore, these results support the use of priming exercise as a precompetition intervention to improve oxidative metabolism and performance during short-duration high-intensity cycling exercise, independent of the pacing strategy adopted.

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Nathan G. Lawler, Chris R. Abbiss, Aaron Raman, Timothy J. Fairchild, Garth L. Maker, Robert D. Trengove and Jeremiah J. Peiffer

Purpose:

To examine the influence of manipulating aerobic contribution after whole-blood removal on pacing patterns, performance, and energy contribution during self-paced middle-distance cycling.

Methods:

Seven male cyclists (33 ± 8 y) completed an incremental cycling test followed 20 min later by a 4-min self-paced cycling time trial (4MMP) on 6 separate occasions over 42 d. The initial 2 sessions acted as familiarization and baseline testing, after which 470 mL of blood was removed, with the remaining sessions performed 24 h, 7 d, 21 d, and 42 d after blood removal. During all 4MMP trials, power output, oxygen uptake, and aerobic and anaerobic contribution to power were determined.

Results:

4MMP average power output significantly decreased by 7% ± 6%, 6% ± 8%, and 4% ± 6% at 24 h, 7 d, and 21 d after blood removal, respectively. Compared with baseline, aerobic contribution during the 4MMP was significantly reduced by 5% ± 4%, 4% ± 5%, and 4% ± 10% at 24 h, 7 d, and 21 d, respectively. The rate of decline in power output on commencement of the 4MMP was significantly attenuated and was 76% ± 20%, 72% ± 24%, and 75% ± 35% lower than baseline at 24 h, 21 d, and 42 d, respectively.

Conclusion:

Removal of 470 mL of blood reduces aerobic energy contribution, alters pacing patterns, and decreases performance during self-paced cycling. These findings indicate the importance of aerobic energy distribution during self-paced middle-distance events.

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Jonathan Watkins, Simon Platt, Erik Andersson and Kerry McGawley

Purpose:

The aim of the current study was to investigate pacing strategies and the distribution of physiological resources in best vs worst performances during a series of 4-min self-paced running time trials (RunTTs).

Methods:

Five male and 5 female recreational runners (age 32 ± 7 y) completed a submaximal ramp test and 5 RunTTs on a motor-driven treadmill fitted with a speed-controlling laser system. The supramaximal oxygen-uptake (V̇O2) demand was estimated by linear extrapolation from the submaximal relationship between V̇O2 and speed, enabling computation of the accumulated oxygen deficit.

Results:

There were no significant differences between the 5 RunTTs for any of the performance, physiological, or subjective responses (P > .05). The trial-to-trial variability in pacing (ie, separate quarters) was typically low, with an average within-athlete coefficient of variation of 3.3%, being highest at the start and end of the 4 min. Total distance covered and distance covered over the first and last 2 min for best and worst performances were 1137 ± 94 and 1090 ± 89 (P < .001), 565 ± 53 and 526 ± 40 m (P = .002), and 572 ± 47 and 565 ± 54 m (P = .346), respectively.

Conclusions:

Negative pacing strategies were evident during both the best and the worst performances of the RunTT. Best performances were characterized by more aggressive pacing over the first 2 min compared with worst performances. In addition, the relatively low trial-to-trial variability in running speed suggests that pacing strategies are similar during a series of 4-min self-paced running time trials.

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Nancy Getchell, Samuel J. Mackenzie and Adam R. Marmon

This study examined the effect of short-term auditory pacing practice on dual motor task performance in children with and without dyslexia. Groups included dyslexic with Movement Assessment Battery for Children (MABC) scores > 15th percentile (D_HIGH, n = 18; mean age 9.89 ± 2.0 years), dyslexic with MABC ≤ 15th percentile (D_LOW, n = 15; mean age 10.43 ± 1.8 years), and typically developing (TD, n = 18; mean age 10.64 ± 1.8 years). Participants clapped and walked simultaneously for 3 pretest trials, completed 16 trials with auditory pacing, and 3 posttest trials without pacing. D_LOW differed significantly from D_HIGH and TD in mean relative phase (MRP) of the clap relative to the step, and variability (VRP) of the MRP. Significant differences also existed between pretest blocks and all other blocks in MRP. The results suggest that a short-term auditory pacing may be effective in improving MRP in all children. Further, there may be subtypes of dyslexia wherein children have more profound coordination difficulties and may preferentially change dual motor task performance with auditory pacing.

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Louise Martin, Anneliese Lambeth-Mansell, Liane Beretta-Azevedo, Lucy A. Holmes, Rachel Wright and Alan St Clair Gibson

Purpose:

Given the paucity of research on pacing strategies during competitive events, this study examined changes in dynamic high-resolution performance parameters to analyze pacing profiles during a multiple-lap mountain-bike race over variable terrain.

Methods:

A global-positioning-system (GPS) unit (Garmin, Edge 305, USA) recorded velocity (m/s), distance (m), elevation (m), and heart rate at 1 Hz from 6 mountain-bike riders (mean ± SD age = 27.2 ± 5.0 y, stature = 176.8 ± 8.1 cm, mass = 76.3 ± 11.7 kg, VO2max = 55.1 ± 6.0 mL · kg−1 . min−1) competing in a multilap race. Lap-by-lap (interlap) pacing was analyzed using a 1-way ANOVA for mean time and mean velocity. Velocity data were averaged every 100 m and plotted against race distance and elevation to observe the presence of intralap variation.

Results:

There was no significant difference in lap times (P = .99) or lap velocity (P = .65) across the 5 laps. Within each lap, a high degree of oscillation in velocity was observed, which broadly reflected changes in terrain, but high-resolution data demonstrated additional nonmonotonic variation not related to terrain.

Conclusion:

Participants adopted an even pace strategy across the 5 laps despite rapid adjustments in velocity during each lap. While topographical and technical variations of the course accounted for some of the variability in velocity, the additional rapid adjustments in velocity may be associated with dynamic regulation of self-paced exercise.

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Alex Garn and Haichun Sun

The use of fitness testing is a practical means for measuring components of health-related fitness, but there is currently substantial debate over the motivating effects of these tests. Therefore, the purpose of this study was to examine the cross-fertilization of achievement and friendship goal profiles for early adolescents involved in the Progressive Aerobic Cardiovascular Endurance Run (PACER). Participants were 214 middle school students who reported their achievement goals, social goals, and preparation effort toward a PACER test. Performance was also examined. Confirmatory factor analysis supported the six-factor approach–avoidance model. Cluster analysis highlighted three distinct profiles. The high-goals profile group reported significantly higher amounts of effort put forth in preparation for the PACER test. Our findings suggest that the cross-fertilization of approach and avoidance achievement and social goals can provide important information about effort and performance on fitness testing in middle school physical education.

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Patrycja Lipinska, Sian V. Allen and Will G. Hopkins

Purpose:

Pacing has a substantial effect on endurance performance. The authors characterize pacing and identify its parameters for optimal performance in 1500-m freestyle swimming.

Methods:

Web sites provided 50-m lap and 1500-m race times for 330 swims of 24 elite male swimmers. Pacing for each swim was characterized with 7 parameters derived from a general linear model: linear and quadratic coefficients for the effect of lap number; reductions from predicted time for first, second, penultimate, and last laps; and lap-time variability. Scatter plots of race time vs each parameter for each swimmer were used to identify optimum values of parameters.

Results:

Most scatterplots showed only weak relationships between the parameter and performance, but one-third to one-half of swimmers had an optimum value of the parameter that was substantially different from their mean value. A large improvement in performance time (1.4% ± 0.9%, mean ± SD) could be achieved generally by reversing the sign of the linear parameter to make the slowest lap occur earlier in the race. Small to moderate improvements might also accrue by changing the quadratic parameter, by making the first and second laps slower and the penultimate and last laps faster, and reducing lap-time variability.

Conclusions:

This approach to analysis of pacing may help improve performance in swimmers and other endurance athletes in sports with multiple laps, but data from many competitions are required.

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Ross Tucker, Michael I. Lambert and Timothy D. Noakes

Purpose:

To analyze pacing strategies employed during men's world-record performances for 800-m, 5000-m, and 10,000-m races.

Methods:

In the 800-m event, lap times were analyzed for 26 world-record performances from 1912 to 1997. In the 5000-m and 10,000-m events, times for each kilometer were analyzed for 32 (1922 to 2004) and 34 (1921 to 2004) world records.

Results:

The second lap in the 800-m event was significantly slower than the first lap (52.0 ± 1.7 vs 54.4 ± 4.9 seconds, P < .00005). In only 2 world records was the second lap faster than the first lap. In the 5000-m and 10,000-m events, the first and final kilometers were significantly faster than the middle kilometer intervals, resulting in an overall even pace with an end spurt at the end.

Conclusion:

The optimal pacing strategy during world-record performances differs for the 800-m event compared with the 5000-m and 10,000-m events. In the 800-m event, greater running speeds are achieved in the first lap, and the ability to increase running speed on the second lap is limited. In the 5000-m and 10,000-m events, an end spurt occurs because of the maintenance of a reserve during the middle part of the race. In all events, pacing strategy is regulated in a complex system that balances the demand for optimal performance with the requirement to defend homeostasis during exercise.

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Anthony P. Turner, Taylor Smith and Simon G.S. Coleman

Purpose:

To evaluate the reliability and sensitivity to training of an audio-paced incremental swimming test.

Methods:

Eight young national-level male swimmers (age 15 ± 1 year) performed a 7 × 200-m incremental swimming test (velocities 1.19, 1.24, 1.28, 1.33, 1.39, and 1.45 m/s and maximal sprint pace) using an audio-pacing device. The same test was performed 4 times by each participant, 1 wk apart to assess reliability (WK1, WK2) and after 9 and 20 wk of training (WK9, WK20). Blood lactate concentration ([La]) and heart rate (HR) were recorded after each stage. Outcome measures were the velocity (v) and HR at lactate markers of 2 mM, 4 mM, and Δ1 mM.

Results:

Velocities at the lactate markers proved to be more reliable than HR, with typical errors ranging from 0.66% to 2.30% and 1.28% to 4.50%, respectively (shifts in mean ranged –0.91% to 0.73% and –0.84% to 1.79%, respectively). Across WK1, WK9, and WK20 there were significant improvements in peak velocity (P < .001) and each of the velocities associated with the lactate markers (P < .05), whereas only HR at Δ1 mM improved (P < .05).

Conclusions:

This article demonstrates that an audio-paced incremental swimming test is reliable for use with junior swimmers and is sensitive to changes observed after training. The postswimming measurement of HR in the pool was comparatively less reliable.

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Rikstje Wiersma, Inge K. Stoter, Chris Visscher, Florentina J. Hettinga and Marije T. Elferink-Gemser

Purpose:

To provide insight on the development of pacing behavior in junior speed skaters and analyze possible differences between elite, subelite, and nonelite juniors.

Methods:

Season-best times (SBTs) in the 1500-m and corresponding pacing behavior were obtained longitudinally for 104 Dutch male speed skaters at age 13–14 (U15), 15–16 (U17), and 17–18 (U19) y. Based on their U19 SBT, skaters were divided into elite (n = 17), subelite (n = 64), and nonelite (n = 23) groups. Pacing behavior was analyzed using the 0- to 300-m, 300- to 700-m, 700- to 1100-m, and 1100- to 1500-m times, expressed as a percentage of final time. Mixed analyses of variance were used for statistical analyses.

Results:

With age, pacing behavior generally developed toward a slower 0- to 300-m and 1100- to 1500-m and a faster midsection relative to final time. While being faster on all sections, the elite were relatively slower on 0- to 300-m (22.1% ± 0.27%) than the subelite and nonelite (21.5% ± 0.44%) (P < .01) but relatively faster on 300- to 700-m (24.6% ± 0.30%) than the nonelite (24.9% ± 0.58%) (P = .002). On 700- to 1100-m, the elite and subelite (26.2% ± 0.25%) were relatively faster than the nonelite (26.5% ± 0.41%) (P = .008). Differences in the development of pacing behavior were found from U17 to U19, with relative 700- to 1100-m times decreasing for the elite and subelite (26.2% ± 0.31% to 26.1% ± 0.27%) but increasing for the nonelite (26.3% ± 0.29% to 26.5% ± 0.41%) (P = .014).

Conclusions:

Maintaining high speed into 700 to 1100 m, accompanied by a relatively slower start, appears crucial for high performance in 1500-m speed skating. Generally, juniors develop toward this profile, with a more pronounced development toward a relatively faster 700- to 1100-m from U17 to U19 for elite junior speed skaters. The results of the current study indicate the relevance of pacing behavior for talent development.