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1.
Sports Biomech ; : 1-16, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38193478

RESUMEN

The aim of this study was to examine spatiotemporal and joint kinematic differences between footstrike patterns in 10,000 m running. Seventy-two men's and 42 women's footstrike patterns were analysed during laps 5, 10, 15, 20 and 25 (of 25) using 2D video recordings. Approximately 47% of men were FFS throughout the race, 30% were MFS and 24% RFS; the respective frequencies in women were approximately 30%, 38% and 32%. Overall, 83% of men and 88% of women retained their footstrike pattern throughout the race. Amongst the 53 men and 33 women with symmetrical footstrike patterns, there were no differences in speed, step length or cadence between footstrike groups in either sex. Most lower limb joint angles did not change in these athletes during the event, with few differences between footstrike patterns apart from ankle and foot angles. A greater hip-ankle distance was found in RFS than in FFS (both sexes) and in RFS than in MFS (men only), although these differences were never more than 0.03 m. Coaches should note that habitual footstrike patterns were maintained during this long-distance track race despite changes in running speed and possible fatigue, and there were few performance differences between footstrike patterns.

2.
Eur J Appl Physiol ; 124(4): 1143-1149, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37922023

RESUMEN

PURPOSE: The aim of this study was to explore the ergogenic effect of advanced footwear technology (AFT) upon world-class male marathon running speed. METHOD: A retrospective analysis of 99 world-class male marathon runners' performances between 2012 and 2021 was undertaken, providing a sample size of 971 performances, split into two footwear groups: AFT (n = 299) and traditional (n = 672). Additionally, details regarding the year of the marathon performance and racecourse were extracted. A mixed model for repeated measures (MMRM) analysis were undertaken identifying athlete (Wald Z = 2.821; p = .005) and course (Wald Z = 4.111; p < 0.001) as significant contributors to the variance in marathon running speed and as such were included as random factors with footwear type set as a fixed factor. RESULTS: World-class male marathon running speeds were significantly faster (p < 0.001) when running in AFT (5.441 m.s-1) when compared with traditional shoes (5.386 m.s-1) with a mean difference of 0.055 m.s-1 (95% CI 0.039-0.071 m.s-1), translating to an improvement in marathon speed of 1.0% or a 79 s improvement in marathon race time. CONCLUSION: Our findings demonstrate an improvement in world-class male marathon running speed of 1% when running in AFT, a near identical degree of improvement to the male marathon world record ran in AFT. Whilst a 1% improvement in marathon running times associated with AFT is smaller than previously predicted utilizing laboratory-based models, this still reflects a significant degree of improvement at the elite level.


Asunto(s)
Carrera de Maratón , Carrera , Humanos , Masculino , Estudios Retrospectivos , Factores de Tiempo , Zapatos
3.
Front Physiol ; 13: 828710, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35721540

RESUMEN

Purpose: The purpose of this study was to look for a new, simple, and fast method of assessing and monitoring indoor race performance and to assess the relationship between 20 s, 60 s, and 2000 m indoor rowing performances of youth rowers to evaluate their anaerobic profile. Methods: For three consecutive days, 17 young able-bodied male rowers (15.8 ± 2.0 years), performed three tests (20 s, 60 s, and 2000 m) on a rowing ergometer. Mean power (W20, W60, and W2000) and 2000 m time (t2000) were considered for the analysis. In addition, 14 athletes (15-18 years) performed a 20 s, 60 s, and 2000 m tests and used this as a control group. To define the anaerobic profile of the athletes, W20 and W60 were normalized as percentages of W2000. Associations between variables were determined by means of the Pearson correlation coefficient (r). Results: Mean power decreased with increasing test duration (W20 = 525.1 ± 113.7 W; W60 = 476.1 ± 91.0 W; W2000=312.9 ± 56.0 W) and negative correlations emerged between t2000 (418.5 ± 23.1 s) and W20 (r = -0.952, p < 0.0001) and W60 (r = -0.930, p < 0.0001). Conclusion: These findings indicate that W20 and W60 are significant predictors of 2000 m rowing ergometer performances. Furthermore, normalized W20 and W60 can be used to evaluate athletes and as a reference for planning anaerobic training sessions, on a rowing ergometer.

4.
Front Physiol ; 13: 838704, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35514331

RESUMEN

Background: Ultra-marathon running participation has become increasingly more popular in recent years; however, there is inconclusive evidence concerning the effects of participation on cognition and cardiovascular function. The purpose of this study was to examine alterations in cardiovascular function and cognitive performance and their association in ultra-marathon runners prior to and following an ultra-endurance event. Methods: In total, 24 runners (19 males and 5 females) participated in an ultra-marathon race (FatDog120) held in British Columbia, Canada. Participants competed in varying races distances [48 km (n = 2), 80 km (n = 7), 113 km (n = 3), and 193 km (n = 12)]. Cognition was assessed prior to and upon race completion using simple reaction time, choice reaction time, discrimination reaction time, and recognition memory (% correct). Cardiovascular function was assessed prior to and upon race completion using radial applanation tonometry for diastolic pulse contour examination. Results: Cognitive performance displayed significantly (p < 0.001) slower reaction times post-race for simple (30.2%), discrimination (22.7%), and choice reaction time (30.5%), as well as a significant (p < 0.05) reduction in memory test performance (-8.2%). A significant association between systemic vascular resistance and choice reaction time was observed post-race (r = 0.41, p < 0.05). Significant changes in post-race cardiovascular function were observed in resting heart rate (31.5%), cardiac output (27.5%), mean arterial blood pressure (-5.6%), total systemic resistance (-17.6%), systolic blood pressure (-7.0%), pulse pressure (-11.2%), and rate pressure product (22.4%). There was evidence of enhanced cardiovascular function being associated with improved cognitive performance before and after the ultra-endurance event. Conclusion: Ultra endurance running is associated with marked impairments in cognitive performance that are associated (at least in part) with changes in cardiovascular function in healthy adults.

5.
Front Sports Act Living ; 3: 714107, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34693282

RESUMEN

Professional road cycling is a very competitive sport, and many factors influence the outcome of the race. These factors can be internal (e.g., psychological preparedness, physiological profile of the rider, and the preparedness or fitness of the rider) or external (e.g., the weather or strategy of the team) to the rider, or even completely unpredictable (e.g., crashes or mechanical failure). This variety makes perfectly predicting the outcome of a certain race an impossible task and the sport even more interesting. Nonetheless, before each race, journalists, ex-pro cyclists, websites and cycling fans try to predict the possible top 3, 5, or 10 riders. In this article, we use easily accessible data on road cycling from the past 20 years and the Machine Learning technique Learn-to-Rank (LtR) to predict the top 10 contenders for 1-day road cycling races. We accomplish this by mapping a relevancy weight to the finishing place in the first 10 positions. We assess the performance of this approach on 2018, 2019, and 2021 editions of six spring classic 1-day races. In the end, we compare the output of the framework with a mass fan prediction on the Normalized Discounted Cumulative Gain (NDCG) metric and the number of correct top 10 guesses. We found that our model, on average, has slightly higher performance on both metrics than the mass fan prediction. We also analyze which variables of our model have the most influence on the prediction of each race. This approach can give interesting insights to fans before a race but can also be helpful to sports coaches to predict how a rider might perform compared to other riders outside of the team.

6.
Artículo en Inglés | MEDLINE | ID: mdl-34064188

RESUMEN

Cross-country mountain biking is an Olympic sport discipline with high popularity among elite and amateur cyclists. However, there is a scarcity of data regarding the key determinants of performance, particularly in young cross-country cyclists. The aim of this study was to examine the physiological profile of youth national-level cross-country cyclists and to determine those variables that were able to best predict the performance in an official race. Ten youth cross-country cyclists of a national team underwent a complete evaluation that included anthropometric assessments, laboratory tests to evaluate the wattage at blood lactate thresholds and at maximal oxygen uptake (POVO2max), and field tests to make an in-depth power profile of the athletes. The data obtained in the above-mentioned tests was analysed along with total and partial race times during a competition belonging to the Union Cycliste Internationale (UCI) calendar. In the present study, large and statistically significant correlations (r = -0.67 to -0.95, p ≤ 0.05) were found between maximal and submaximal indices of aerobic fitness and cycling performance, especially when they were normalised to body mass. A multiple regression analysis demonstrated that the wattage at 2 mmol/L, 4 mmol/L and POVO2max were able to explain 82% of the variance in total race time. In summary, the results of this study support the use of maximal and submaximal indices of aerobic power as predictors of performance in youth cross-country cyclists.


Asunto(s)
Ciclismo , Deportes , Adolescente , Antropometría , Ejercicio Físico , Prueba de Esfuerzo , Humanos , Consumo de Oxígeno
7.
Vet Med Sci ; 7(5): 2039-2042, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33955192

RESUMEN

This is the first prospective study to investigate the impact of mitochondrial DNA (mtDNA) on race performance in a closely bred family of racing pigeons in one breeding loft where there is a high percentage of male and female birds related to one foundation hen, Queen L by Jelle Roziers. This study shows that in this family of birds, which are all related to Queen L, there is no advantage of having mtDNA with regard to race performance on the longer distances. The results of this study reject the hypothesis that mtDNA genes are related to long-distance performance. Actually, this analysis indicates that those birds in this family with no mtDNA from Queen L may have better race performance on the shorter distances than those with mtDNA. This suggests that there are other genetic factors which may be related to race performance in this family of racing pigeons.


Asunto(s)
Columbidae , ADN Mitocondrial , Animales , Pollos/genética , Columbidae/genética , ADN Mitocondrial/genética , Femenino , Masculino , Estudios Prospectivos
8.
Int J Sports Physiol Perform ; 16(11): 1610-1615, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-33848975

RESUMEN

PURPOSE: To determine aerobic and anaerobic demands of mountain bike cross-country racing. METHODS: Twelve elite cyclists (7 males; V˙O2max = 73.8 [2.6] mL·min-1·kg-1, maximal aerobic power [MAP] = 370 [26] W, 5.7 [0.4] W·kg-1, and 5 females; V˙O2max = 67.3 [2.9] mL·min-1·kg-1, MAP = 261 [17] W, 5.0 [0.1] W·kg-1) participated over 4 seasons at several (119) international and national races and performed laboratory tests regularly to assess their aerobic and anaerobic performance. Power output, heart rate, and cadence were recorded throughout the races. RESULTS: The mean race time was 79 (12) minutes performed at a mean power output of 3.8 (0.4) W·kg-1; 70% (7%) MAP (3.9 [0.4] W·kg-1 and 3.6 [0.4] W·kg-1 for males and females, respectively) with a cadence of 64 (5) rev·min-1 (including nonpedaling periods). Time spent in intensity zones 1 to 4 (below MAP) were 28% (4%), 18% (8%), 12% (2%), and 13% (3%), respectively; 30% (9%) was spent in zone 5 (above MAP). The number of efforts above MAP was 334 (84), which had a mean duration of 4.3 (1.1) seconds, separated by 10.9 (3) seconds with a mean power output of 7.3 (0.6) W·kg-1 (135% [9%] MAP). CONCLUSIONS: These findings highlight the importance of the anaerobic energy system and the interaction between anaerobic and aerobic energy systems. Therefore, the ability to perform numerous efforts above MAP and a high aerobic capacity are essential to be competitive in mountain bike cross-country.


Asunto(s)
Ciclismo , Tolerancia al Ejercicio , Anaerobiosis , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Estaciones del Año
9.
Eur J Sport Sci ; 21(11): 1559-1566, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33106120

RESUMEN

This study aimed to analyse differences in pacing profiles in four marathon competitions and to explore that pacing per time category. A database of 91,493 runners gathered from 4 different races was analysed (Valencia, Chicago, London and Tokyo Marathon). Participants were categorized in accordance with their completion time. The relative speed of each section for each runner was calculated as a percentage of the average speed for the entire race. In the four marathons studied, the first 5 km differed widely, presenting London the highest relative speeds (5 km: CI95% London vs. Valencia [12.1, 13.6%], p < 0.001 and ES = 2.1; London vs. Chicago [5.5, 7.1%], p < 0.001 and ES = 1.1; London vs. Tokyo [15.2, 16.8%], p < 0.001 and ES = 2.3). Races did not differ at each section for high-performance runners (sub-2:30), but differences between races increased as the time category increases (e.g. 35 km and sub-3:00: CI95% London vs. Tokyo [-3.1, -1.8%], p < 0.001 and ES = 0.7; 35 km and sub-5:00: London vs. Tokyo [-9.8, -9.2%], p < 0.001 and ES = 1.3). The difference in relative speed between the first and second half of the marathon was higher in London than in the other marathons (e.g. CI95% London vs. Valencia [10.3, 10.8%], p < 0.001 and ES = 1.3). In conclusion, although race characteristics affect pacing, this effect was higher as the category time increases. Race pacing characteristics should be taken into consideration for runners and coaches choosing the race and working on pacing strategies, for researches to extrapolate or interpret results, or for race organizations to improve its pacing characteristics.


Asunto(s)
Rendimiento Atlético/clasificación , Conducta Competitiva/clasificación , Carrera de Maratón/clasificación , Resistencia Física , Humanos , Factores de Tiempo
10.
Artículo en Inglés | MEDLINE | ID: mdl-33344935

RESUMEN

The purpose of this study was to examine whether World Championship and Olympic medallist endurance athletes pace similarly to their race opponents, where and when critical differences in intra-race pacing occur, and the tactical strategies employed to optimally manage energy resources. We analyzed pacing and tactics across the 800, 1,500, 5,000, 10,000 m, marathon and racewalk events, providing a broad overview for optimal preparation for racing and pacing. Official electronic splits from men's (n = 275 performances) and women's (n = 232 performances) distance races between 2013 and 2017 were analyzed. Athletes were grouped for the purposes of analysis and comparison. For the 800 m, these groups were the medalists and those finishing 4th to 8th ("Top 8"). For the 1,500 m, the medalists and Top 8 were joined by those finishing 9th to 12th ("Top 12"), whereas for all other races, the Top 15 were analyzed (those finishing 9th to 15th). One-way repeated measures analysis of variance was conducted on the segment speeds (p < 0.05), with effect sizes for differences calculated using Cohen's d. Positive pacing profiles were common to most 800 m athletes, whereas negative pacing was more common over longer distances. In the 1,500 m, male medalists separated from their rivals in the last 100 m, whereas for women it was after 1,200 m. Similarly, over 5,000 m, male medalists separated from the slowest pack members later (4,200 m; 84% of duration) than women (2,500 m; 50% of duration). In the 10,000 m race, the effect was very pronounced with men packing until 8,000 m, with the Top 8 athletes only dropped at 9,600 m (96% of duration). For women, the slowest pack begin to run slower at only 1,700 m, with the Top 8 finishers dropped at 5,300 m (53% of duration). Such profiles and patterns were seen across all events. It is possible the earlier separation in pacing for women between the medalists and the other runners was because of tactical racing factors such as an early realization of being unable to sustain the required speed, or perhaps because of greater variation in performance abilities.

11.
J Hum Kinet ; 51: 45-51, 2016 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-28149367

RESUMEN

Triathletes exiting the swim portion of an event have to decide on how and when to take a wetsuit off (if worn). The purpose of this study was to determine the physiological cost of running while not using a wetsuit, carrying a wetsuit, wearing a wetsuit halfway down or wearing a wetsuit fully up. Participants (n = 20, 30.9 ± 8.7 yrs, 1.71 ± 0.08 m, 71.6 ± 9.5 kg) completed four 5 min running conditions: 1) not wearing the wetsuit, 2) wearing the wetsuit fully up, 3) wearing the wetsuit halfway down, and 4) carrying the wetsuit. A rate of oxygen uptake, a heart rate, ratings of perceived exertion and stride frequency were measured and were each influenced by wetsuit condition (p < 0.05). Each variable (i.e., a rate of oxygen uptake, a heart rate, stride frequency) was lower during running while not wearing the wetsuit vs. any other condition (p < 0.05). The rate of oxygen uptake was greatest during wearing the wetsuit halfway down vs. any other condition (p < 0.05). The heart rate was not different between any of the combinations of either wearing the wetsuit fully up or halfway down or carrying the wetsuit (p > 0.05). The rating of perceived exertion was greater during wearing the wetsuit halfway down vs. carrying the wetsuit (p < 0.05). Stride frequency was lower during not wearing the wetsuit vs. wearing the wetsuit halfway down or fully up (p < 0.05). It was concluded that running with the wetsuit halfway down resulted in the greatest rate of oxygen uptake, heart rate and rating of perceived exertion.

12.
Ciênc. rural ; 45(7): 1268-1273, 07/2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-749774

RESUMEN

Evaluations of the physical fitness of Thoroughbred racehorses have been correlated with race earnings, but few reports exist about the influence of the distance exercised during training on both physical conditioning indices and financial productivity. During one training season sixteen claiming Thoroughbred horses were subjected to submaximal training and monitored by a global positioning system (GPS) coupled to a heart rate monitor. After initial and single monitoring, the horses were distributed into two groups of eight individuals each; one group exercised short distances (SD) between 1600 and 1900m, while the other exercised long distances (LD) between 2000 and 2350m. The duration (min) and mean and maximal velocities (ms-1)attained during each session were determined, as well as the difference in distances exercised (m) between official races and each training session. Blood lactate concentration ([LA]) during recovery was also determined. Student's t-test was used for a non-paired analysis, with P≤0.05 considered significant. The winnings (USD) of each horse were correlated with the peak heart rate (HRpeak) attained during the training session. The distances exercised in the training sessions were greater in relation to the official races distances by 24.7% and 40% for SD and LD, respectively. Lactatemia did not differ between the groups. The HRpeak obtained during the training session was lower in LD group. The velocity at which the heart rate reached 200 bpm (V200) was higher in LD group. There was a moderate correlation (r= 0.42) between the highest winnings and lowest HRpeak. The horses that ran longer distances during their submaximal training session had better cardiac conditioning and tendency to increase financial productivity.


Avaliações da aptidão física de cavalos Puro Sangue Inglês (PSI) têm sido correlacionadas com o ganho financeiro, mas a influência da distância percorrida durante o treinamento, tanto sobre índices de condicionamento físico como na produtividade financeira tem sido pouco relatada. Monitoraram-se, por meio de global positioning system (GPS) acoplado a frequencímetro, numa temporada de treinamento, dezesseis equinos da raça PSI, de uma mesma categoria, submetidos a treinamento submáximo. Após o monitoramento inicial e único de uma sessão de treino, os equinos foram distribuídos em dois grupos de oito componentes (DC e DL) diferenciados de acordo com a distância percorrida durante cada sessão de treino, sendo DC para distância curta e DL para distância longa. Dessa maneira, DC e DL percorreram distâncias entre 1600-1900 e 2000-2350 metros, respectivamente. Determinaram-se o tempo e as velocidades médias e máximas atingidas (m s-1), bem como a diferença entre as distâncias percorridas (m) entre as corridas oficiais e as sessões. A produção de lactato sanguíneo durante a recuperação foi quantificada. Empregou-se teste t de student para análise não pareada, sendo P≤0,05. Correlacionaram-se os ganhos financeiros (USD) de cada cavalo com afrequência cardíaca de pico (FCpico) atingidas durante as sessões. As distâncias percorridas nos treinos foram maiores em relação às corridas oficiais em 24,7% e 40% para DC e DL, respectivamente. A lactatemia não diferiu entre os grupos. A frequência cardíaca de pico (FCpico) obtida durante as sessões foi menor para o grupo DL. A velocidade que a frequência cardíaca atingiu 200 bpm (V200) foi maior para DL. Houve correlação moderada entre os maiores ganhos financeiros e menores FCpico. Os cavalos que treinaram maiores distâncias durante sessões de treinamento submáximo tiveram melhor condicionamento cardíaco e maior produtividade financeira.

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