54 research outputs found
The Impact of Different Competitive Environments on Pacing and Performance.
Purpose: In real-life competitive situations, athletes are required to continuously make decisions about how and when to invest their available energy resources. This study attempted to identify how different competitive environments invite elite short-track speed skaters to modify their pacing behaviour during head-to-head competition. Methods: Lap times of elite 500, 1000 and 1500 m short-track speed skating competitions between 2011–2016 (n=34095 races) were collected. Log-transformed lap and finishing times were analysed with mixed linear models. The fixed effects in the model were sex, season, stage of competition, start position, competition importance, event number per tournament, number of competitors per race, altitude, and time qualification. The random effects of the model were Athlete identity and the residual (within-athlete race-to-race variation). Separate analyses were performed for each event. Results: Several competitive environments, such as the number of competitors in a race (a higher number of competitors evoked most likely a faster initial pace; CV=1.9-9.3%), the stage of competition (likely to most likely, a slower initial pace was demonstrated in finals; CV=-1.4-2.0%), the possibility of time qualification (most likely a faster initial pace; CV=2.6-5.0%) and competition importance (most likely faster races at the Olympics; CV=1.3-3.5%), altered the pacing decisions of elite skaters in 1000 and 1500 m events. Stage of competition and start position affected 500 m pacing behaviour. Conclusion: As demonstrated in this study, different competitive environments evoked modifications in pacing behavior, in particular in the initial phase of the race, emphasizing the importance of athlete-environment interactions, especially during head-to-head competitions
Pacing and Self-regulation: Important Skills for Talent Development in Endurance Sports
Pacing has been characterized as a multifaceted goal-directed process of decision making in which athletes need to decide how and when to invest their energy during the race, a process essential for optimal performance. Both physiological and psychological characteristics associated with adequate pacing and performance are known to develop with age. Consequently, the multifaceted skill of pacing might be under construction throughout adolescence, as well. Therefore, the authors propose that the complex skill of pacing is a potential important performance characteristic for talented youth athletes that needs to be developed throughout adolescence. To explore whether pacing is a marker for talent and how talented athletes develop this skill in middle-distance and endurance sports, they aim to bring together literature on pacing and literature on talent development and self-regulation of learning. Subsequently, by applying the cyclical process of self-regulation to pacing, they propose a practical model for the development of performance in endurance sports in youth athletes. Not only is self-regulation essential throughout the process of reaching the long-term goal of athletic excellence, but it also seems crucial for the development of pacing skills within a race and the development of a refined performance template based on previous experiences. Coaches and trainers are advised to incorporate pacing as a performance characteristic in their talent-development programs by stimulating their athletes to reflect, plan, monitor, and evaluate their races on a regular basis to build performance templates and, as such, improve their performance
Self-regulation of effort for a better health-related quality of life: a multidimensional activity pacing model for chronic pain and fatigue management
Qualification patterns of Olympic and IAAF World Championship middle distance runners
The 800 m and 1500 m are the two middle distance events contested at the Olympic Games and other major championships. On most occasions, athletes must negotiate two qualifying rounds to reach the final. The theoretically optimal method of competing in these rounds is to obtain an automatic qualifying position in the slowest possible finishing time; however, elite athletes are often ego oriented and this might have led them to try to win all races. The aim of this study was to identify whether elite athletes adopted these theoretically optimal tactics, or whether the will to win overrode them. Finishing positions and times of the eventual finalists in the men’s and women’s 800 m and 1500 m competitions at Olympic Games and IAAF World Championships between 1999 and 2017 were analysed. The performances of 606 athletes were analysed (800 m men: 122; 800 m women: 120; 1500 m men: 183; 1500 women: 181). The finalists’ finishing positions and times, as well as their overall ranking in the heats and semi-finals, were also obtained. Athletes were allocated to groups based on finishing position in the final: medallists (800 m and 1500 m), non-medallists finishing in the top eight (‘Top 8’: 800 m and 1500 m), and those athletes finishing outside the top eight (‘Top 12’: 1500 m only). One-way repeated measures ANOVA was conducted on the heat, semi-final and final finishing times. In addition, one-way ANOVA were conducted with Tukey’s post-hoc tests to compare finishing times between groups. Statistical significance was accepted as P < .05. Kendall’s tau-b (τb) correlations determined the relationships between finishing position in the final with qualifying round positional, rank and finishing time data. Across the four events, 70% of the 57 gold medallists won both qualifying rounds, whereas 36% of the silver medallists and 19% of the bronze medallists achieved the same positions. Nineteen gold medallists set a season’s best or personal best time in the final. In each event, finishing position in the final was correlated with finishing position in the heats and semi-finals (P ≤ 0.002), but not with finishing time in those rounds. In the 800 m, medallists were faster than non-medallists in the final only (P < 0.001); in the 1500 m, medallists and Top 8 finishers were faster than Top 12 finishers in the final only (P < 0.001). Most World and Olympic champions won both their heat and semi-final, even though this was unnecessary, but managed to do so with slower times than in the final. These tactics showed a long-term pacing strategy that optimised overall competition success. In addition, the gold medallists did so in most cases in times slower than their best that year. Head-to-head elite championships, where winning is more important than time recorded, encourage a performance climate for both men and women athletes where ego orientation is more likely to occur
Pacing Profiles in Competitive Track Races: Regulation of Exercise Intensity is related to Cognitive Ability
Pacing has been defined as the goal-directed regulation of exercise intensity over an exercise bout, in which athletes need to decide how and when to invest their energy. The purpose of this study was to explore if the regulation of exercise intensity during competitive track races is different between runners with and without intellectual impairment, which is characterized by significant limitations in intellectual functioning (IQ ≤ 75) and adaptive behavioral deficits, diagnosed before the age of 18. The samples included elite runners with intellectual impairment (N = 36) and a comparison group of world class runners without impairment (N = 39), of which 47 were 400 m runners (all male) and 28 were 1500 m-runners (15 male and 13 female). Pacing was analyzed by means of 100 m split times (for 400 m races) and 200 m split times (for 1500 m races). Based on the split times, the average velocity was calculated for four segments of the races. Velocity fluctuations were defined as the differences in velocity between consecutive race segments. A mixed model ANOVA revealed significant differences in pacing profiles between runners with and without intellectual impairment (p < 0.05). Maximal velocity of elite 400 m runners with intellectual impairment in the first race segment (7.9 ± 0.3 m/s) was well below the top-velocity reached by world level 400 m runners without intellectual impairment (8.9 ± 0.2 m/s), and their overall pace was slower (F = 120.7, p < 0.05). In addition, both groups followed a different pacing profile and inter-individual differences in pacing profiles were larger, with differences most pronounced for 1500 m races. Whereas, male 1500 m-runners without intellectual impairment reached a high velocity in the first 100 m (7.2 ± 0.1 m/s), slowly decelerated in the second race segment (−0.6 ± 0.1 m/s), and finished with an end sprint (+0.9 ± 0.1 m/s); the 1500 m runners with intellectual impairment started slower (6.1 ± 0.3 m/s), accelerated in the second segment (+0.2 ± 0.7 m/s), and then slowly decreased until the finish (F = 6.8, p < 0.05). Our findings support the hypothesis that runners with intellectual impairment have difficulties to efficiently self-regulate their exercise intensity. Their limited cognitive resources may constrain the successful integration of appropriate pacing strategies during competitive races
Meso-pacing in Olympic and World Championship sprints and hurdles: Medallists save their best for the final
The aim of this novel study was to analyse performance changes across qualifying heats, semi-finals and finals in world-class sprinters and hurdlers. Finalists’ finishing positions, times and rankings at the Olympic Games and IAAF World Championships (2012 – 2019) were obtained. 78% of gold, 67% of silver and 38% of bronze medallists won their qualifying heat and semi-final, and in most events final placings were associated with finishing positions in the qualifying heats (P ≤ 0.006), but not with finishing times. Medallists ran faster in each successive round (P < 0.001), whereas those finishing between 4th-6th did not improve on their semi-final times. Most athletes finishing last and second-last ran the final slower than both their semi-final and qualifying heats. The short hurdles events, with fixed barrier heights and distances, differed from the other races as the medallists were faster than most rivals in the qualifying rounds (P < 0.05), and their race times did not improve from the semi-final to the final. Coaches should note that the world’s best athletes were able to conserve energy for the final within a meso-pacing strategy throughout the championships, which was more important in the short hurdles, and requires preparation within their training regimens
Development of 1500m Pacing Behavior in Junior Speed Skaters: A Longitudinal Study.
Providing insight in the development of pacing behavior in junior speed skaters and analyse possible differences between elite, sub-elite, and non-elite juniors.1500m season best times (SBT) 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) years. Based on their U19 SBT, skaters were divided into elite(n=17), sub-elite(n=64), and non-elite(n=23) groups. Pacing behavior was analysed using the 0-300m, 300-700m, 700-1100m and 1100-1500m times, expressed as a percentage of final time. Mixed analyses of variance were used for statistical analyses.With age, pacing behavior generally developed towards a slower 0-300m and 1100-1500m and a faster mid-section relative to final time. While being faster on all sections, the elite were relatively slower on 0-300m (22.1±0.27%) than the sub-elite and non-elite (21.5±0.44%)(p<0.01), but relatively faster on 300-700m (24.6±0.30%) than the non-elite (24.9±0.58%)(p=0.002). On 700-1100m, the elite and sub-elite (26.2±0.25%) were relatively faster than the non-elite (26.5±0.41%)(p=0.008). Differences in the development of pacing behavior were found from U17-U19 with relative 700-1100m times decreasing for the elite and sub-elite (26.2±0.31% to 26.1±0.27%), but increasing for the non-elite (26.3±0.29% to 26.5±0.41%)(p=0.014).Maintaining high speed into 700-1100m, accompanied by a relatively slower start, appears crucial for high performance on the 1500m speed skating. Generally, juniors develop towards this profile, with a more pronounced development towards a relative faster 700-1100m from U17-U19 for elite junior speed skaters. The results of the present study indicate the relevance of pacing behavior for talent development
Are there associations with age and sex in walking stability in healthy older adults?
The variability of the centre of pressure (COP) during walking can provide information in relation to stability when walking. The aim of this study was to investigate if age and sex were associated with COP variability, COP excursions, and COP velocities during walking. One-hundred and fourteen older adults (age 65.1 ± 5.5 yrs.) participated in the study. A Kistler force platform (1000 Hz) recorded the ground reaction forces and COPs during walking at a self-selected walking speed. The stance phase was divided, using the vertical GRF, into four sub-phases: loading response (LR), mid-stance (MSt), terminal stance (TSt), and pre-swing (PSw). The standard deviations of the COP displacement (variability), the COP velocity, and COP excursion in the medial–lateral and anterior–posterior directions, as well as the resultant magnitude were assessed. When controlling for walking speed, a greater age was associated with a higher variability and excursion of the COP during LR only suggesting that stability is maintained during the majority of the stance phase. During LR lower COP velocity was significantly associated for females for anterior-posterior and total COP, which may be a strategy to facilitate stability before, and moving into, MSt and TSt
Handcycling: training effects of a specific dose of upper body endurance training in females
Purpose: This study aims to evaluate a handcycling training protocol based on ACSM guidelines in a well-controlled laboratory setting. Training responses of a specific dose of handcycling training were quantified in a homogeneous female subject population to obtain a more in depth understanding of physiological mechanisms underlying adaptations in upper body training. Methods: 22 female able-bodied participants were randomly divided in a training (T) and control group (C). T received 7-weeks of handcycling training, 3 × 30 min/week at 65 % heart rate reserve (HRR). An incremental handcycling test was used to determine local, exercise-specific adaptations. An incremental cycling test was performed to determine non-exercise-specific central/cardiovascular adaptations. Peak oxygen uptake (peakVO2), heart rate (peakHR) and power output (peakPO) were compared between T and C before and after training. Results: T completed the training sessions at 65 ± 3 % HRR, at increasing power output (59.4 ± 8.2 to 69.5 ± 8.9 W) over the training program. T improved on handcycling peakVO2 (+18.1 %), peakPO (+31.9 %), and peakHR (+4.0 %). No improvements were found in cycling parameters. Conclusion: Handcycling training led to local, exercise-specific improvements in upper body parameters. Results could provide input for the design of effective evidence-based training programs specifically aimed at upper body endurance exercise in females
The effect of ambient temperature on gross-efficiency in cycling
Time-trial performance deteriorates in the heat. This might potentially be the result of a temperature-induced decrease in gross-efficiency (GE). The effect of high ambient temperature on GE during cycling will be studied, with the intent of determining if a heat-induced change in GE could account for the performance decrements in time trial exercise found in literature. Ten well-trained male cyclists performed 20-min cycle ergometer exercise at 60%
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\begin{document}\end{document} (power output at which VO2max was attained) in a thermo-neutral climate (N) of 15.6 ± 0.3°C, 20.0 ± 10.3% RH and a hot climate (H) of 35.5 ± 0.5°C, 15.5 ± 3.2% RH. GE was calculated based on VO2 and RER. Skin temperature (Tsk), rectal temperature (Tre) and muscle temperature (Tm) (only in H) were measured. GE was 0.9% lower in H compared to N (19.6 ± 1.1% vs. 20.5 ± 1.4%) (P < 0.05). Tsk (33.4 ± 0.6°C vs. 27.7 ± 0.7°C) and Tre (37.4 ± 0.6°C vs. 37.0 ± 0.6°C) were significantly higher in H. Tm was 38.7 ± 1.1°C in H. GE was lower in heat. Tm was not high enough to make mitochondrial leakage a likely explanation for the observed reduced GE. Neither was the increased Tre. Increased skin blood flow might have had a stealing effect on muscular blood flow, and thus impacted GE. Cycling model simulations showed, that the decrease in GE could account for half of the performance decrement. GE decreased in heat to a degree that could explain at least part of the well-established performance decrements in the heat
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