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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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Patrick P.J.M. Schoenmakers, Florentina J. Hettinga, and Kate E. Reed

Purpose: Over recent years, multiple studies have tried to optimize the exercise intensity and duration of work intervals in high-intensity-interval training (HIIT) protocols. Although an optimal work interval is of major importance to facilitate training adaptations, an optimal HIIT protocol can only be achieved with an adequate recovery interval separating work bouts. Surprisingly, little research has focused on the acute responses and long-term impact of manipulating recovery intervals in HIIT sessions. This invited commentary therefore aimed to review and discuss the current literature and increase the understanding of the moderating role of recovery durations in HIIT protocols. Conclusion: The acute responses to manipulations in recovery durations in repeated-sprint training (RST), sprint interval training (SIT), and aerobic interval training (AIT) protocols have recently begun to receive scientific interest. However, limited studies have manipulated only the recovery duration in RST, SIT, or AIT protocols to analyze the role of recovery durations on long-term training adaptations. In RST and SIT, longer recovery intervals (≥80 s) facilitate higher workloads in subsequent work intervals (compared with short recovery intervals), while potentially lowering the aerobic stimulus of the training session. In AIT, the total physiological strain endured per training protocol appears not to be moderated by the recovery intervals, unless the recovery duration is too short. This invited commentary highlights that further empirical evidence on a variety of RST, SIT, and AIT protocols and in exercise modalities other than cycling is needed.

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Stein G.P. Menting, Marco J. Konings, Marije T. Elferink-Gemser, and Florentina J. Hettinga

Purpose: To gain insight into the development of pacing behavior of youth athletes in 1500-m short-track speed-skating competition. Methods: Lap times and positioning of elite short-track skaters during the seasons 2011/2012–2015/2016 were analyzed (N = 9715). The participants were grouped into age groups: under 17 (U17), under 19 (U19), under 21 (U21), and senior. The difference between age groups, sexes, and stages of competition within each age group were analyzed through a multivariate analysis of variance (P < .05) of the relative section times (lap time as a percentage of total race time) per lap and by analyzing Kendall tau-b correlations between intermediate positioning and final ranking. Results: The velocity distribution over the race differed between all age groups, explicitly during the first 4 laps (U17: 7.68% [0.80%], U19: 7.77% [0.81%], U21: 7.82% [0.81%], and senior: 7.80% [0.82%]) and laps 12, 13, and 14 (U17: 6.92% [0.14%], U19: 6.83% [0.13%], U21: 6.79% [0.14%], and senior: 6.69% [0.12%]). In all age groups, a difference in velocity distribution was found between the sexes and between finalists and nonfinalists. Positioning data demonstrated that youth skaters showed a higher correlation between intermediate position and final ranking in laps 10, 11, and 12 than seniors. Conclusions: Youth skaters displayed less conservative pacing behavior than seniors. The pacing behavior of youths, expressed in relative section times and positioning, changed throughout adolescence and came to resemble that of seniors. Pacing behavior and adequately responding to environmental cues in competition could therefore be seen as a self-regulatory skill that is under development throughout adolescence.

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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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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.

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Inge K. Stoter, Brian R. MacIntosh, Jared R. Fletcher, Spencer Pootz, Inge Zijdewind, and Florentina J. Hettinga

Purpose:

To evaluate pacing behavior and peripheral and central contributions to muscle fatigue in 1500-m speed-skating and cycling time trials when a faster or slower start is instructed.

Methods:

Nine speed skaters and 9 cyclists, all competing at regional or national level, performed two 1500-m time trials in their sport. Athletes were instructed to start faster than usual in 1 trial and slower in the other. Mean velocity was measured per 100 m. Blood lactate concentrations were measured. Maximal voluntary contraction (MVC), voluntary activation (VA), and potentiated twitch (PT) of the quadriceps muscles were measured to estimate central and peripheral contributions to muscle fatigue. In speed skating, knee, hip, and trunk angles were measured to evaluate technique.

Results:

Cyclists showed a more explosive start than speed skaters in the fast-start time trial (cyclists performed first 300 m in 24.70 ± 1.73 s, speed skaters in 26.18 ± 0.79 s). Both trials resulted in reduced MVC (12.0% ± 14.5%), VA (2.4% ± 5.0%), and PT (25.4% ± 15.2%). Blood lactate concentrations after the time trial and the decrease in PT were greater in the fast-start than in the slow-start trial. Speed skaters showed higher trunk angles in the fast-start than in the slow-start trial, while knee angles remained similar.

Conclusions:

Despite similar instructions, behavioral adaptations in pacing differed between the 2 sports, resulting in equal central and peripheral contributions to muscle fatigue in both sports. This provides evidence for the importance of neurophysiological aspects in the regulation of pacing. It also stresses the notion that optimal pacing needs to be studied sport specifically, and coaches should be aware of this.

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Jos J. de Koning, Carl Foster, Alejandro Lucia, Maarten F. Bobbert, Florentina J. Hettinga, and John P. Porcari

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Dionne A. Noordhof, Elmy van Tok, Florentine S.J.G.M. Joosten, Florentina J. Hettinga, Marco J.M. Hoozemans, Carl Foster, and Jos J. de Koning

Half the improvement in 1500-m speed-skating world records can be explained by technological innovations and the other half by athletic improvement. It is hypothesized that improved skating economy is accountable for much of the athletic improvement. Purpose: To determine skating economy in contemporary athletes and to evaluate the change in economy over the years. Methods: Contemporary skaters of the Dutch national junior team (n = 8) skated 3 bouts of 6 laps at submaximal velocity, from which skating economy was calculated (in mL O2 ・ kg–1 ・ km–1). A literature search provided historic data on skating velocity and submaximal V̇O2 (in mL ・ kg–1 ・ min–1), from which skating economy was determined. The association between year and skating economy was determined using linear-regression analysis. Correcting the change in economy for technological innovations resulted in an estimate of the association between year and economy due to athletic improvement. Results: A mean (± SD) skating economy of 73.4 ± 6.4 mL O2 ・ kg–1 ・ km–1 was found in contemporary athletes. Skating economy improved significantly over the historical time frame (–0.57 mL O2 ・ kg–1 ・ km–1 ・ y–1, 95% confidence interval [–0.84, –0.31]). In the final regression model for the klapskate era, with altitude as confounder, skating economy improved with a nonsignificant –0.58 mL O2 ・ kg–1 ・ km–1 ・ y–1 ([–1.19, 0.035]). Conclusions: Skating economy was 73.4 ± 6.4 mL O2 ・ kg–1 ・ km–1 in contemporary athletes and improved over the past ~50 y. The association between year and skating economy due to athletic improvement, for the klapskate era, approached significance, suggesting a possible improvement in economy over these years.