Objectifying Tactics: Athlete and Race Variability in Elite Short-Track Speed Skating

Purpose: To objectively capture and understand tactical considerations in a race, the authors explored whether race-to-race variation of an athlete and the variation of competitors within a race could provide insight into how and when athletes modify their pacing decisions in response to other competitors. Methods: Lap times of elite 500-, 1000-, and 1500-m short-track speed-skating competitions from 2011 to 2016 (N = 6965 races) were collected. Log-transformed lap and finishing times were analyzed with mixed linear models. To determine within-athlete race-to-race variability, athlete identity (between-athletes differences) and the residual (within-athlete race-to-race variation) were added as random effects. To determine race variability, race identity (between-races differences) and the residual (within-race variation) were added as random effects. Separate analyses were performed for each event. Results: Within-athlete race-to-race variability of the finishing times increased with prolonged distance of the event (500-m, CV = 1.6%; 1000-m, CV = 2.8%; 1500-m, CV = 4.1%), mainly due to higher within-athlete race-to-race variability in the initial phase of 1000-m (3.3–6.9%) and 1500-m competitions (8.7–12.2%). During these early stages, within-race variability is relatively low in 1000-m (1.1–1.4%) and 1500-m (1.3–2.8%) competitions. Conclusion: The present study demonstrated how analyses of athlete and race variability could provide insight into tactical pacing decisions in sports where finishing position is emphasized over finishing time. The high variability of short-track skaters is a result of the decision to alter initial pacing behavior based on the behavior of other competitors in their race, emphasizing the importance of athlete–environment interactions in the context of pacing

Pacing Decision Making in Sport and the Effects of Interpersonal Competition: A Critical Review

An athlete’s pacing strategy is widely recognised as an essential determinant for performance during individual events. Previous research focussed on the importance of internal bodily state feedback, revealed optimal pacing strategies in time-trial exercise, and explored concepts such as teleoanticipation and template formation. Recently, human–environment interactions have additionally been emphasized as a crucial determinant for pacing, yet how they affect pacing is not well understood. Therefore, this literature review focussed on exploring one of the most important human–environment interactions in sport competitions: the interaction among competitors. The existing literature regarding the regulation of exercise intensity and the effect of competition on pacing and performance is critically reviewed in this paper. The PubMed, CINAHL and Web of Science electronic databases were searched for studies about pacing in sports and (interpersonal) competition between January 2000 to October 2017, using the following combination of terms: (1) Sports AND (2) Pacing, resulting in 75 included papers. The behaviour of opponents was shown to be an essential determinant in the regulation of exercise intensity, based on both observational (N = 59) and experimental (N = 16) studies. However, adjustment in the pacing response related to other competitors appears to depend on the competitive situation and the current internal state of the athlete. The findings of this review emphasize the importance of what is happening around the athlete for the outcome of the decision-making process involved in pacing, and highlight the necessity to incorporate human–environment interactions into models that attempt to explain the regulation of exercise intensity in sports and exercise

Maximal and submaximal aerobic tests for wheelchair-dependent persons with spinal cord injury: a systematic review to summarize and identify useful applications for clinical rehabilitation

Purpose: To summarize the available maximal and submaximal aerobic exercise tests for wheelchair-dependent persons with a spinal cord injury (SCI) and to identify useful applications for clinical rehabilitation. Method: The databases of PubMed, CINAHL®, EMBASE, and PsycINFO® were searched for English-language studies published prior to March 2015. Two independent raters identified and examined studies that reported on laboratory-based aerobic exercise tests in persons with an SCI, according to the PRISMA statement. Results: The test protocols of maximal (n = 105) and submaximal (n = 28) exercise tests, covered by 95 included studies, were assessed. A large variety in patient characteristics, test objectives, test protocols, exercise modes, and outcome parameters was reported. Few studies reported on adherence to recommendations, adverse events, and peak outcome validation. Conclusions: An incremental test protocol with small, individualized, increments per stage seems preferable for testing maximal aerobic capacity, but additional validation of the available test modes is required to draw conclusions. Submaximal testing is relevant for assessing the performance at daily life intensities and for estimating VO2peak. Consensus regarding reporting test procedures and outcomes needs to be achieved to enhance comparability of rehabilitation results

Biomechanics in Paralympics: Implications for Performance

Purpose: To provide an overview of biomechanical studies in Paralympic research and their relevance for performance in Paralympic sports. Methods: The search terms paralympic biomechanics, paralympic sport performance, paralympic athlete performance, and paralympic athlete were entered into the electronic database PubMed. Results: Thirty-four studies were found. Biomechanical studies in Paralympics mainly contributed to performance enhancement by technical optimization (n = 32) and/or injury prevention (n = 6). In addition, biomechanics was found to be important in understanding activity limitation caused by various impairments, which is relevant for evidence-based classification in Paralympic sports (n = 6). Distinctions were made between biomechanical studies in sitting (41%), standing (38%), and swimming athletes (21%). In sitting athletes, mostly kinematics and kinetics in wheelchair propulsion were studied, mainly in athletes with spinal-cord injuries. In addition, kinetics and/or kinematics in wheelchair basketball, seated discus throwing, stationary shot-putting, hand-cycling, sit-skiing, and ice sledge hockey received attention. In standing sports, primarily kinematics of athletes with amputations performing jump sports and running and the optimization of prosthetic devices were investigated. No studies were reported on other standing sports. In swimming, mainly kick rate and resistance training were studied. Conclusions: Biomechanical research is important for performance by gaining insight into technical optimization, injury prevention, and evidence-based classification in Paralympic sports. In future studies it is advised to also include physiological and biomechanical measures, allowing the assessment of the capability of the human body, as well as the resulting movement

Pacing Behavior and Tactical Positioning in 1500-m Short-Track Speed Skating

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.</jats:sec

The behavior of an opponent alters pacing decisions in 4-km cycling time trials

Introduction: The present study aimed to explore how athletes respond to different behaviors of their opponents. Methods: Twelve moderately to highly physically active participants with at least two years of cycling experience completed four 4-km time trials on a Velotron cycle ergometer. After a familiarization time trial (FAM), participants performed three experimental time trials in randomized order with no opponent (NO), a virtual opponent who started slower and finished faster compared to FAM (OP-SLOWFAST), or a virtual opponent who started faster and finished slower compared to FAM (OP-FASTSLOW). Repeated-measures ANOVAs (P < 0.05) were used to examine differences in pacing and performance related to power output, velocity and RPE. Results: OP-SLOWFAST and OP-FASTSLOW were completed faster compared to NO (385.5 ± 27.5, 385.0 ± 28.6, and 390.6 ± 29.3 s, respectively). An interaction effect for condition × distance (F = 3.944, P < 0.001) indicated differences in pacing profiles between conditions. Post-hoc analysis revealed that a less aggressive starting strategy was adopted in NO compared to OP-FASTSLOW and OP-SLOWFAST during the initial 1000 m. Finally, a faster starting opponent evokes higher power outputs by the participants in the initial 750 m compared to a slower starting opponent. Conclusion: The present study is the first to show that the behavior of an opponent affects pacing-related decisions in laboratory-controlled conditions. Our findings support the recently proposed interdependence of perception and action, and emphasize the interaction with the environment as an important determinant for an athlete's pacing decisions, especially during the initial stages of a race

You don't need to administer a placebo to elicit a placebo effect: Social factors trigger neurobiological pathways to enhance sports performance

The placebo effect is traditionally viewed as a positive outcome resulting from a person’s belief that an inert substance is in fact an active drug. In this context, it is often viewed as an intrapsychic phenomenon. However, most placebo effects reported in scientific research result from social interactions. These might be explicit, such as the description and administration of a treatment by a practitioner, or less explicit, for example, the recipient’s perceptions of the practitioner’s credibility, expertise, or confidence. On this basis, placebo effects are arguably social in origin. Many phenomena in sport are likewise social in origin, from the facilitation effects of a home field crowd or a cohesive team, to anxiety induced by an expert opponent or perceived underperformance. Such social effects have been the subject of research not only in social psychology, but also in experimental physiology. Emergent research in cognitive and evolutionary anthropology suggests that these social effects can be examined as a form of placebo effect. This suggestion is not a speculative position predicated on social and placebo effects sharing similar environmental cues and outcomes, but one based on a growing database indicating that drug, placebo, and social effects operate via common neurobiological mechanisms. In this paper, we examine the theoretical and empirical overlap between placebo and social effects and describe emergent research reporting specific brain pathways activated by socio-environmental cues as well as by drugs and placebos. We do so from three perspectives: the competitor, the teammate, the researcher

Sex differences in wheelchair propulsion biomechanics and mechanical efficiency in novice young able-bodied adults

An awareness of sex differences in gait can be beneficial for detecting the early stages of gait abnormalities that may lead to pathology. The same may be true for wheelchair propulsion. The aim of this study was to determine the effect of sex on wheelchair biomechanics and mechanical efficiency in novice young able-bodied wheelchair propulsion. Thirty men and 30 women received 12  min of familiarisation training. Subsequently, they performed two 10-m propulsion tests to evaluate comfortable speed (CS). Additionally, they performed a 4-min submaximal propulsion test on a treadmill at CS, 125% and 145% of CS. Propulsion kinetics (via Smartwheel) and oxygen uptake were continuously measured in all tests and were used to determine gross mechanical efficiency (GE), net efficiency (NE) and fraction of effective force (FEF). Ratings of perceived exertion (RPE) were assessed directly after each trial. Results indicated that CS for men was faster (0.98 ± 0.24 m/s) compared to women (0.71 ± 0.18 m/s). A lower GE was found in women compared to men. Push percentage, push angle and local RPE were different across the three speeds and between men and women. NE and FEF were not different between groups. Thus, even though their CS was lower, women demonstrated a higher locally perceived exertion than men. The results suggest sex differences in propulsion characteristics and GE. These insights may aid in optimising wheelchair propulsion through proper training and advice to prevent injuries and improve performance. This is relevant in stimulating an active lifestyle for those with a disability

Pacing Behavior and Tactical Positioning in 500- and 1000-m Short-Track Speed Skating

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