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1.
J Sports Sci ; 42(12): 1164-1172, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39101451

RESUMEN

Wearables quantify the activity in team sports and indicate that players experience peak physical loads during competitions. Accordingly, players with limited court time in competitions will miss important training stimuli. The present study aimed to quantify these gaps in physical load in professional handball players. Activity of all players competing in the 2021/2022 Bundesliga (Germany) was tracked using Kinexon LPS sensors. Gaps in physical load were quantified comparing the 25% of appearances with the highest (HIGH; 51.8 ± 5.2 mins) and lowest court times (LOW; 10.1 ± 4.3 mins). Distances, accumulated acceleration, jumps, sprints, impacts, accelerations, and decelerations were analysed as absolute and relative (per minute) outcomes. Players were grouped into wings, backcourts, and pivots. Unpaired t-tests between HIGH and LOW were performed (p < .05), and effect sizes were calculated (Cohen´s d). Analyses revealed significant effects of court time on activity. While absolute activity increased for HIGH, relative activity increased for LOW (p < .05). In addition, effect sizes revealed position-specific gaps in physical load, particularly for acyclic activities (jumps, accelerations). Gaps in physical load resulting from limited court time are highly position-specific. Our observations may provide benchmarks for the position-specific calibration of compensatory training.


Asunto(s)
Aceleración , Rendimiento Atlético , Conducta Competitiva , Humanos , Rendimiento Atlético/fisiología , Conducta Competitiva/fisiología , Deportes/fisiología , Estudios de Tiempo y Movimiento , Masculino , Deportes de Equipo , Factores de Tiempo , Adulto Joven , Acondicionamiento Físico Humano , Adulto
2.
Sensors (Basel) ; 24(14)2024 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-39065932

RESUMEN

This study aimed to explore how positional performance varies across different youth age groups and during matches in football competitions. The study encompassed 160 male outfield youth football players (n = 80, under-13, U13; n = 80, under-15, U15) who belonged to the starting line-up and played the entire first half of each match. The players' positional data were gathered through the global positional system for each of the eight matches performed by each age group. The frequency of near-in-phase synchronization based on speed displacements, spatial exploration index, and the distance to the nearest teammate and opponent were used as variables. Additionally, each match half was segmented into three equal parts to assess changes over time and used as a period factor along with age group. The results indicated that U13 players showed a significant decrease (from small to large ES) in synchronization speed and spatial exploration index throughout the first half of the match, along with a decrease in the distance to the nearest opponent. In contrast, U15 players exhibited most changes during the third segment of the half, with a decrease in speed synchronization and spatial exploration, but an increase in the distance and regularity to the nearest opponent. Comparing both age groups revealed significant differences in speed synchronization across the entire half of the match and within each segmented period (from small to large ES), with U13 consistently showing higher values. The study highlights that long durations in 11 vs. 11 matches might not provide an appropriate learning environment in the U13 age group. Conversely, the U15 group displayed better capacity for tactical adjustments over time, suggesting a higher level of tactical maturity. Overall, these findings emphasize the importance of adapting youth football training and competition structures to the developmental needs and capabilities of different age groups to optimize learning and performance outcomes.


Asunto(s)
Rendimiento Atlético , Fútbol , Humanos , Rendimiento Atlético/fisiología , Masculino , Adolescente , Fútbol/fisiología , Niño , Factores de Edad , Conducta Competitiva/fisiología , Carrera/fisiología
3.
J Sports Sci ; 42(12): 1112-1119, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39058913

RESUMEN

This study examined the frequency of the most demanding scenarios (MDS) during official soccer matches using rolling averages over 1, 5, and 10 min. Forty-two Under-19 players from different positions (central defenders, full-backs, central midfielders, wide midfielders, offensive midfielders, and forwards) were monitored across 27 matches using GPS to track distance covered, high-speed running, sprint distance, accelerations, and decelerations. Intensity thresholds were established based on percentiles (0-25, 25-50, 50-75, 75-100, and ≥100). The main findings suggest that: (i) Peak Demands occur in less than 1% of all time windows and variables for all positions; (ii) Most efforts occur below peak demands, with around 95% for high-speed running and sprint distance, and 85% for accelerations, decelerations, and total distance; (iii) Significant differences in intensity distributions were found between positions, particularly at medium-low and high intensities. Regarding training prescription, relying solely on MDS may be limited, highlighting the need to supplement MDS with other metrics for a comprehensive understanding of match demands. This approach ensures better-informed training programs for soccer players.


The occurrence of peak demand events during soccer matches is infrequent. Therefore, understanding the frequency of efforts below the intensity threshold of the most demanding passages for each playing position and across various analysed variables and periods is of utmost importance.MDS might not be enough for effective soccer training planning. Complementing with additional metrics like GPS, tactical analysis, physiological data and psychological factors is essential for a comprehensive understanding of the game's demands and tailored training programmes.


Asunto(s)
Aceleración , Rendimiento Atlético , Desaceleración , Sistemas de Información Geográfica , Carrera , Fútbol , Fútbol/fisiología , Humanos , Carrera/fisiología , Rendimiento Atlético/fisiología , Adolescente , Conducta Competitiva/fisiología , Masculino , Estudios de Tiempo y Movimiento , Acondicionamiento Físico Humano/fisiología
4.
J Sports Sci ; 42(11): 971-980, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39082736

RESUMEN

Recently, a variety of technical approaches in world-class pole-vaulters' behaviour have been observed. The aim of this study was to investigate the presence of subgroups using different technical approaches and to compare biomechanical performance differences. Biomechanical analysis of performances over 5.00 metres from 99 athletes were clustered with K-means methodology based on the relative position of the top hand at take-off and the direction of the top of the pole from take-off to the maximal pole bending. Analysis revealed four subgroups that were distinguished by higher and lower direction angle and relative position values. Despite differences in technique, the analysis did not reveal significant differences between these four groups in performance, take-off speed, or athlete anthropometrics. Nevertheless, these clusters showcased variations in pole-athlete interactions and pole bending, suggesting different strategies and physical requirements associated with each approach. Cluster 2 characterised the classical technique with a high direction angle and a take-off position close to the vertical plane. Cluster 4 displayed a technique with a low take-off angle, suggesting the influence of athletes like Lavillenie, in deviating from the conventional model. Understanding and categorising athletes based on their preferred technique can aid coaches in providing tailored instructions, leading to performance improvements.


Asunto(s)
Rendimiento Atlético , Conducta Competitiva , Humanos , Fenómenos Biomecánicos , Rendimiento Atlético/fisiología , Masculino , Conducta Competitiva/fisiología , Análisis por Conglomerados , Destreza Motora/fisiología , Femenino , Equipo Deportivo , Adulto Joven , Atletismo/fisiología , Adulto , Antropometría , Estudios de Tiempo y Movimiento , Análisis y Desempeño de Tareas
5.
J Sports Sci ; 42(11): 959-970, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39010316

RESUMEN

This study constructs a discrete-time Markov Chain (DTMC) model for a baseball plate appearance (PA) employing Major League Baseball's pitch-by-pitch dataset. Based on the DTMC model, we propose a novel measure for a baseball PA, termed the Importance of Moment (IOM). The IOM quantifies the criticality of each ball-strike count situation, by assessing the probabilistic difference between the pitcher's and hitter's favourable outcomes (out vs reaching base). If the favours significantly vary right after a particular ball-strike count, then the count is deemed critical and is assigned a high IOM value. We empirically verify that IOM explains pitchers' behaviour of fastball speed. We then further investigate whether the behaviour of ace pitchers differs significantly from the majority. Several interesting properties are found from the analysis. Firstly, the path independence assumption generally holds, with the exception of the ball-strike count of 2B1S. Second, pitchers tend to throw the faster fastball at counts with higher IOM values. Lastly, ace pitchers are capable of pitching even faster fastball in two-strike situations in which IOM is high. The DTMC effectively models the probabilistic structure of a baseball PA, and the proposed IOM measure serves as a useful tool for explaining player behaviour.


Asunto(s)
Rendimiento Atlético , Béisbol , Cadenas de Markov , Béisbol/fisiología , Humanos , Rendimiento Atlético/fisiología , Conducta Competitiva/fisiología
6.
J Sports Sci ; 42(11): 1002-1010, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39036961

RESUMEN

The aim of this study was to create a novel metric, Expected Pass Turnovers (xPT), that could evaluate possession retention from player-passing events in football. Event and positional data were analysed from all 380 matches in the 2020/21 English Premier League season, which encompassed 256,433 passes in the final dataset. A logistic mixed-effects model was implemented to attribute the probability of each pass getting turned over. The use of positional data enabled the identification of a) opposition players present in radii surrounding the ball carrier and b) availability of teammates with respect to the ball carrier. The addition of these positional features improved the accuracy (+6.1 AUC Score) of the model. xPT serves as a practitioner Key Performance Indicator, as analysts can identify players that lose possession more often or not than expected, given the situational context of each pass, from game to game. Future work may include modelling the turnover probability of dribble and carry actions, as this would lead to a more comprehensive understanding of turnover events in football.


Asunto(s)
Rendimiento Atlético , Conducta Competitiva , Fútbol , Fútbol/fisiología , Humanos , Rendimiento Atlético/fisiología , Conducta Competitiva/fisiología , Modelos Logísticos
7.
Aggress Behav ; 50(4): e22166, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39030757

RESUMEN

Being aggressive and by extension, dominant, is an important mechanism for determining access to resources such as mates or territories. While predictors of contest outcome and dominance are increasingly studied, we have a poor understanding of how they vary across populations. Here, I use the widely distributed Australian agamid lizard, the Jacky dragon (Amphibolurus muricatus), to quantify variation in features predicting contest outcome among males of different populations. I measured physical attributes, maximal physiological performance capacity (sprint speed, endurance, bite force) and visual displays during staged encounters. I found that morphology, performance capacity and the type and frequency of visual displays used during agonistic interactions varied significantly across populations. Contest winners from the Cann River State Forest population favored tail-flicks and push-up/body-rocks, while those from Royal National Park were more likely to chase and individuals from Yarratt State Forest performed more bite-lunges than other populations. The losers of contests also differed in their displays. Individuals from the Cann River population were dominant over the others based on behavioral attributes (i.e., aggressive visual displays, chases and bite-lunges). I suggest that population differences in signal form and function could have implications for range dynamics as populations come into contact in an era of rapid environmental change.


Asunto(s)
Lagartos , Lagartos/fisiología , Masculino , Animales , Conducta Competitiva/fisiología , Conducta Animal/fisiología , Agresión/fisiología , Australia
8.
J Int Soc Sports Nutr ; 21(1): 2377178, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39007897

RESUMEN

BACKGROUND: Physique athletes are subjectively judged on their on-stage esthetic per their competition division criteria. To succeed, competitors look to acutely enhance their appearance by manipulating nutritional variables in the days leading up to competition, commonly referred to as peak week (PW). Despite their documented wide adoption, PW strategies lack experimental evidence. Further, the relationship between the specific strategies and the characteristics of the competitors who implement them are unknown. The aim of this research was to examine the effect of competitor characteristics on the specific nutritional peaking strategies implemented, the length of these strategies, and the range of daily carbohydrate (CHO) intakes during these strategies. METHODS: A 58-item survey was developed to gather information on peak week nutrition and training practices of physique athletes. A total of 160 respondents above the age of 18 who had competed in the last 5 years completed the nutrition section. The topics analyzed for this paper included competitor demographics, peaking strategies utilized, and PW CHO intakes. Competitor demographics are presented with the use of descriptive statistics. Associations between competitor demographics and peaking strategies implemented, peaking strategy length, and daily CHO intake ranges were assessed using multiple logistic regression, multiple ordinal logistic regression, and linear mixed models, respectively. RESULTS: From the sampled population, ages 24-39 years (71.2%), male (68.8%), natural (65%), and amateur (90%) were the most common characteristics from their respective categories, while mean competition preparation length was 20.35 ± 8.03 weeks (Males: 19.77 ± 7.56 weeks, Females: 21.62 ± 8.93 weeks), competition preparation body mass loss was 11.5 ± 5.56 kg (M: 12.7 ± 5.76 kg, F: 7.16 ± 3.99 kg), and competition body mass was 72.09 ± 15.74 kg (M: 80.15 ± 11.33 kg, F: 54.34 ± 7.16 kg). For males, the highest and lowest daily CHO intake during PW were 489.63 ± 224.03 g (6.22 ± 2.93 g/kg body mass) and 148.64 ± 152.01 g (1.94 ± 2.17 g/kg), respectively, while for females these values were 266.73 ± 131.23 g (5.06 ± 2.67 g/kg) and 94.42 ± 80.72 g (1.81 ± 1.57 g/kg), respectively. CHO back loading (45%) and water loading (40.6%) were the most popular peaking strategies, while the most prevalent peaking strategy length was 7 days (27.2%). None of the competitor characteristics predicted the use of CHO-based peaking strategies nor peaking strategy length. For non-CHO-based strategies, drug-enhanced competitors were more likely to restrict water than non-drug enhanced, while males and professional competitors had greater odds of loading sodium than females and amateurs, respectively. Finally, when comparing the disparity in highest and lowest CHO intakes during peak week, sex was the only significant factor. CONCLUSIONS: The results of this survey provide further information on the nutritional peaking strategies implemented by competitors. Certain characteristics were identified as predictors of sodium loading and water restriction, and the range of daily PW CHO intake. Contrastingly, no associations were found for CHO-based peaking strategies or peaking strategy length. While our analyses may be underpowered, and thus results should be interpreted with caution, it appears the nutritional peaking strategies implemented by physique competitors are seemingly complex and highly individual.


Asunto(s)
Carbohidratos de la Dieta , Fenómenos Fisiológicos en la Nutrición Deportiva , Humanos , Femenino , Masculino , Adulto , Adulto Joven , Carbohidratos de la Dieta/administración & dosificación , Atletas , Conducta Competitiva/fisiología , Encuestas y Cuestionarios , Rendimiento Atlético/fisiología
9.
Cereb Cortex ; 34(7)2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38989873

RESUMEN

Competition is common in life, and intimate relationships are essential. Understanding how intimate relationships impact an individual's competitive process is crucial. This study explored the impact of competitor gender on female competition using electroencephalography analysis. The results revealed that females exhibited a smaller median of the absolute value of reaction time difference (DRT) between their partners and their competitors when their partners were absent compared to when their partners were present. Additionally, females showed greater average amplitudes of N2 posterior contralateral component (N2pc) and Late Positive Potential (LPP), increased activation of the alpha frequency band, and enhanced theta frequency band functional connectivity between the central parietal lobe and occipital lobe. Furthermore, when competing with individuals of the same gender as opposed to individuals of the opposite gender, females exhibited greater average amplitudes of percentage of wins and N2pc. A significant negative correlation was noted between the DRT and the average wave amplitudes of N2pc and LPP. These findings suggest that females are more engaged in competitive tasks when partners are not present and have improved decision-making when competing with same-gender individuals. This study provides evidence for the influence of lovers on female competition, helping females adapt to social competition and promoting healthy relationships.


Asunto(s)
Encéfalo , Conducta Competitiva , Electroencefalografía , Relaciones Interpersonales , Humanos , Femenino , Adulto Joven , Encéfalo/fisiología , Adulto , Conducta Competitiva/fisiología , Tiempo de Reacción/fisiología , Potenciales Evocados/fisiología , Masculino
10.
Int J Sports Physiol Perform ; 19(8): 773-779, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38834181

RESUMEN

PURPOSE: To compare the standard Yo-Yo intermittent recovery (IR) test and an agility Yo-Yo IR test with a higher number of change-of-direction movements to cardiorespiratory match performance. METHODS: The study included 11 professional male handball players (age 24.5 [4.6] y) of a German second-league team. The performance parameters of the players of the seasons 2016-17 to 2018-19 were analyzed. The Yo-Yo IR test was compared to a Yo-Yo IR test with multiple multidirectional changes of direction in response to visual stimuli, which was conducted on a SpeedCourt (Yo-Yo SC IR). Peak oxygen uptake (VO2peak) and maximum heart rate (HRmax) were measured. Between-methods differences of individual athletes were quantified with Bland-Altman plots. RESULTS: HRmax was not statistically different during the Yo-Yo SC IR test compared to the Yo-Yo IR test (181 [10] vs 188 [8] beats·min-1; P = .16). Agreement between the 2 tests was moderate for HRmax and good for heart rates >180 beats·min-1. Mean average VO2peak was 51.7 (3.9) and 50.9 (2.8) mL·min-1·kg-1 for the Yo-Yo SC IR test and the Yo-Yo IR test (P = .693), respectively. CONCLUSIONS: A Yo-Yo test with multidirectional changes of direction in response to visual stimuli yielded good agreement with the frequently used linear running tests and can be used to assess players' VO2peak. The HRmax achieved during this test should be used with caution.


Asunto(s)
Rendimiento Atlético , Prueba de Esfuerzo , Frecuencia Cardíaca , Consumo de Oxígeno , Resistencia Física , Humanos , Masculino , Frecuencia Cardíaca/fisiología , Consumo de Oxígeno/fisiología , Rendimiento Atlético/fisiología , Adulto Joven , Resistencia Física/fisiología , Prueba de Esfuerzo/métodos , Adulto , Deportes/fisiología , Capacidad Cardiovascular/fisiología , Conducta Competitiva/fisiología
11.
Int J Sports Physiol Perform ; 19(8): 792-797, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38862106

RESUMEN

PURPOSE: To quantify the change in session rating of perceived exertion training impulse (RPE-TRIMP) that may occur in response to increased running distance at 3 running velocity ranges in elite sprinters. METHODS: We monitored training load in elite sprinters (women: n = 7; men: n = 11) using wearable Global Positioning System technology and RPE-TRIMP for a total of 681 individual training sessions during a 22-week competition-preparation period. Internal training load was operationalized by RPE-TRIMP, and external training load was operationalized by distance covered in 3 velocity ranges. A linear mixed-effects model with athlete as a random effect was fit to RPE-TRIMP with total distance covered at ≤69.99% (low-velocity running [LVR]), 70% to 84.99% (high-velocity running [HVR]), and 85% to 100% (very-high-velocity running [VHVR]) of individual maximum velocity. RESULTS: Increased running distance in all 3 velocity ranges (LVR, HVR, and VHVR) resulted in a significant (P < .001) increase in RPE-TRIMP. Coefficients (95% CIs) were .10 (.08-.11) for LVR, .23 (.18-.28) for HVR, and .44 (.35-.53) for VHVR. A 50-m increase in running distance covered in the LVR, HVR, and VHVR velocity ranges was associated with increases in RPE-TRIMP of 5, 11.5, and 22 arbitrary units, respectively. CONCLUSIONS: Internal training load, calculated as RPE-TRIMP, increased with increases in total distance covered in the LVR, HVR, and VHVR velocity ranges (P < .001). RPE-TRIMP can be a practical solution for monitoring global training-session load in elite sprinters.


Asunto(s)
Sistemas de Información Geográfica , Percepción , Acondicionamiento Físico Humano , Esfuerzo Físico , Carrera , Humanos , Masculino , Carrera/fisiología , Esfuerzo Físico/fisiología , Femenino , Acondicionamiento Físico Humano/métodos , Percepción/fisiología , Adulto Joven , Adulto , Conducta Competitiva/fisiología
12.
Int J Sports Physiol Perform ; 19(8): 836-840, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38897574

RESUMEN

PURPOSE: This study aimed to enhance the understanding of soccer match peak demands by describing worst-case scenario (WCS) and time spent above 80% and 90% of the WCS for total distance (TD) and high-speed running (HSR). The investigation considered playing level (first team vs under-19 [U19] team) and playing position (center backs, fullbacks, midfielders, and forwards) to assess how WCS and the time spent above specific thresholds vary across different populations. METHODS: Data from 31 players in a professional Italian soccer club were collected during the 2022-23 season. Microtechnology devices tracked physical activity during matches. Players were categorized by position, and WCS was determined using rolling averages over a 1-minute period. Time spent above 80% and 90% of WCS for TD and HSR was calculated. RESULTS: The U19 team exhibited higher HSR WCS compared with the first team (∼63 m·min-1 vs ∼56 m·min-1). Midfielders recorded the highest TD WCS (∼208 m·min-1), and forwards exhibited the highest HSR WCS (∼70 m·min-1). The first team spent significantly more time above 80% (∼6 min) and 90% (∼1 min) of TD WCS. Midfielders spent significantly more time above the 80% (∼7 min) of TD WCS, while forwards above the 80% (∼2 min) of HSR WCS. CONCLUSIONS: The study emphasizes that WCS used alone may not sufficiently capture real match intensity. Considering the time spent above specific thresholds provides additional insights (ie, between-levels differences and position). Practitioners should consider both WCS and time spent above thresholds for individualized training prescriptions, reflecting differences in playing roles.


Asunto(s)
Rendimiento Atlético , Carrera , Fútbol , Humanos , Fútbol/fisiología , Carrera/fisiología , Rendimiento Atlético/fisiología , Adulto Joven , Conducta Competitiva/fisiología , Masculino , Adulto , Italia , Factores de Tiempo , Estudios de Tiempo y Movimiento
13.
Int J Sports Physiol Perform ; 19(8): 829-832, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38897579

RESUMEN

PURPOSE: Global navigation satellite system device-derived metrics are commonly represented by discrete zones with intensity often measured by standardizing volume to per-minute of activity duration. This approach is sensitive to imprecision in duration measurement and can lead to highly variable outcomes-transforming data from zones to a gradient may overcome this problem. The purpose of this study was to critically evaluate this approach for measuring team-sport activity demands. METHODS: Data were collected from 129 first-team and 73 academy matches from a Scottish Premiership football club. Gradients were calculated for velocity, acceleration, and deceleration zones, along with per-minute values for several commonly used metrics. Means and 95% CIs were calculated for playing level, as well as first-team positional groups. Within-subject coefficients of variation were also calculated for match level, position, and individual groups. RESULTS: The gradient approach showed consistency with per-minute metrics when measuring playing level and position groups. With coefficients of variation of 10.8% to 26.9%, the gradients demonstrated lower variability than most per-minute variables, which ranged from 10.7% to 84.5%. CONCLUSIONS: Gradients are a potentially useful way of describing intensity in team sports and compare favorably to existing intensity variables in their ability to distinguish between match types and position groups, providing evidence that gradient variables can be used to monitor match and training intensity in team sports.


Asunto(s)
Aceleración , Sistemas de Información Geográfica , Fútbol , Deportes de Equipo , Humanos , Fútbol/fisiología , Desaceleración , Conducta Competitiva/fisiología , Rendimiento Atlético/fisiología , Carrera/fisiología , Masculino , Acondicionamiento Físico Humano/métodos
14.
J Sports Med Phys Fitness ; 64(8): 784-792, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38841727

RESUMEN

BACKGROUND: The activity profiles of football players during competition can be affected by the athletes' competitive level and sex. However, evidence of this in youth South American athletes is scarce as is the effects of body composition on match activity profiles. Therefore, the present study compared the activity profiles of Chilean under-20 (U20) and under-17 (U17) male and female teams during the World Cup qualification tournaments (WC) using a multicomponent athlete monitoring system and explored the relationships between these profiles and the players' body composition. METHODS: Athlete's body composition was measured as there were total distance, distance covered at different velocities, explosive efforts, sprints, and estimated player load (PL) during the 2018-2019 World Cup Qualifiers. RESULTS: Males had greater muscle and lower fat mass than females and covered 10.8% more total distance with maximal speed being 15.3% faster in match play (P<0.05). However, females covered more distance at higher running speeds and had a greater number of sprints (P<0.05). For males, the U20 club was 3.7% faster and performed 26.3% more explosive efforts than the U17 club (P<0.05). Contrastingly, the female U17 club covered more total distance, more distance at different speeds had more total sprints, greater PL, and muscle mass than the U20 club (P<0.05). Across all athletes, fat mass correlated negatively to total distance (R=-0.39; P=0.001), while muscle mass correlated positively with maximal speed (R=0.72; P=0.001). CONCLUSIONS: Gender, competitive level, and body composition seem to affect match-activity profiles in football players during WC qualifiers.


Asunto(s)
Rendimiento Atlético , Composición Corporal , Fútbol , Humanos , Masculino , Femenino , Fútbol/fisiología , Composición Corporal/fisiología , Adolescente , Rendimiento Atlético/fisiología , Conducta Competitiva/fisiología , Carrera/fisiología , Chile , Factores Sexuales
15.
Int J Sports Physiol Perform ; 19(7): 712-721, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38823792

RESUMEN

PURPOSE: Postactivation performance enhancement (PAPE), which refers to the phenomena associated with the attainment of enhanced performance in sport-specific tasks after a conditioning activity, is an important objective of warming-up practices in many sports. This is even more relevant for sprinters, as potential increases in sprinting speed will directly influence their competitive results. This systematic review with meta-analysis evaluated the effects of different PAPE protocols (ie, using plyometrics, strength-power exercises, and resisted/assisted sprints) on the sprinting performance (ie, sprint time or sprint speed) of competitive sprinters. METHODS: Initially, 1205 records published until last December 18 were identified, using the following databases: PubMed/MEDLINE, Scopus, and Clarivate Web of Science. After removing duplicates and screening titles and abstracts, 14 high-quality studies met the inclusion criteria for the meta-analysis. RESULTS: Overall, there were no significant changes in sprint performance after implementing various types of conditioning activities (standardized mean difference [SMD] = 0.16 [95% CI, -0.02 to 0.33]; Z = 1.78; P = .08; I2 = 0%). In addition, when comparing prechanges and postchanges between experimental, control, and other conditions, no significant differences were found in sprint speed or time across all studies (SMD = 0.09 [95% CI, -0.10 to 0.28]; Z = 0.92; P = .36; I = 0%). CONCLUSIONS: Results revealed that different types of conditioning activities may not be capable of acutely enhancing the sprint speed of competitive sprinters. This aligns with previous observations indicating that sprinting is a highly stable physical capacity, a phenomenon that is even more consistent among elite sprinters. Coaches and sport scientists should collaborate to develop more efficient PAPE protocols for these highly specialized athletes, with special attention to study design and individualization, while considering their effects on acceleration versus top speed.


Asunto(s)
Rendimiento Atlético , Carrera , Humanos , Rendimiento Atlético/fisiología , Carrera/fisiología , Acondicionamiento Físico Humano/métodos , Ejercicio de Calentamiento/fisiología , Ejercicio Pliométrico , Entrenamiento de Fuerza/métodos , Conducta Competitiva/fisiología
16.
Eur J Sport Sci ; 24(6): 713-720, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38874951

RESUMEN

To investigate the effect of forced even pacing through virtual pacing assistance and an opponent in a competitive setting on end-spurt behaviour in freestyle swimmers, including related physiological underpinnings. Twenty-seven competitive swimmers and triathletes were recruited. There were four 1500 m freestyle trials: (i) familiarisation time trial, (ii) self-paced time trial (STT), (iii) head-to-head competition time trial (CTT) and (iv) forced even pacing through virtual pacing assistance time trial (FET). Eventually, 12 swimmers met the criteria for the CTT and FET to be included in the analysis. Changes in end-spurt behaviour, finishing time and physiological parameters (lactate, cortisol, noradrenaline and heart rate) were analysed using a linear mixed model with fixed effects for trials and a random effect for swimmer identity. A separate linear model was computed for competition outcome. The end-spurt for each race was determined by means of an end-spurt indicator (ESI; ESI > 0 greater end-spurt). Swimmers demonstrated a significantly greater ESI in FET (+2.6; p < 0.001) and CTT (+1.4; p = 0.022) compared to STT. Blood lactate concentration in FET (+1.0 mmol L-1; p < 0.001) and CTT (+1.6 mmol L-1; p < 0.001) was significantly higher than in STT. Winners had a significantly greater ESI than losers in CTT (+1.6 and p = 0.005). Swimmers utilised a greater end-spurt through metabolically optimal forced even pacing by virtual pacing assistance and in a head-to-head competition due a larger mobilisation of anaerobic reserves as indicated by greater blood lactate concentrations. Winners had a significantly greater end-spurt than losers despite similar metabolic disturbances.


Asunto(s)
Rendimiento Atlético , Conducta Competitiva , Frecuencia Cardíaca , Ácido Láctico , Natación , Humanos , Natación/fisiología , Ácido Láctico/sangre , Masculino , Conducta Competitiva/fisiología , Frecuencia Cardíaca/fisiología , Rendimiento Atlético/fisiología , Adulto , Adulto Joven , Femenino , Hidrocortisona/sangre , Norepinefrina/sangre , Atletas
17.
Int J Sports Physiol Perform ; 19(9): 867-873, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38917986

RESUMEN

INTRODUCTION: In distance running, pacing is characterized by changes in speed, leading to runners dropping off the leader's pace until a few remain to contest victory with a final sprint. Pacing behavior has been well studied over the last 30 years, but much remains unknown. It might be related to finishing position, finishing time, and dependent on critical speed (CS), a surrogate of physiologic capacity. We hypothesized a relationship between CS and the distance at which runners "fell behind" and "let go" from the leader or were "outsprinted" as contributors to performance. METHODS: 100-m split times were obtained for athletes in the men's 10,000-m at the 2008 Olympics (N = 35). Split times were individually compared with the winner at the point of "falling behind" (successive split times progressively slower than the winner), "letting go" (large increase in time for distance compared with winner), or "outsprinted" (falling behind despite active acceleration) despite being with the leader with 400 m remaining. RESULTS: Race times ranged between 26:55 and 29:23 (world record = 26:17). There were 3 groups who fell behind at ∼1000 (n = 11), ∼6000 (n = 16), and ∼9000 m (n = 2); let go at ∼4000 (n = 10), ∼7000 (n = 14), and ∼9500 m (n = 5); or were outkicked (n = 6). There was a moderate correlation between CS and finishing position (r = .82), individual mean pace (r = .79), "fell behind" distance (r = .77), and "let go" distance (r = .79). D' balance was correlated with performance in the last 400 m (r = .87). CONCLUSIONS: Athletes displayed distinct patterns of falling behind and letting go. CS serves as a moderate predictor of performance and final placing. Final placing during the sprint is related to preservation of D' balance.


Asunto(s)
Rendimiento Atlético , Conducta Competitiva , Carrera , Humanos , Masculino , Carrera/fisiología , Rendimiento Atlético/fisiología , Conducta Competitiva/fisiología , Aceleración , Adulto , Factores de Tiempo
18.
Hum Nat ; 35(2): 114-133, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38878141

RESUMEN

Humans have undergone a long evolutionary history of violent agonistic exchanges, which would have placed selective pressures on greater body size and the psychophysical systems that detect them. The present work showed that greater body size in humans predicted increased knockout power during combative contests (Study 1a-1b: total N = 5,866; Study 2: N = 44 openweight fights). In agonistic exchanges reflective of ancestral size asymmetries, heavier combatants were 200% more likely to win against their lighter counterparts because they were 200% more likely to knock them out (Study 2). Human dominance judgments (total N = 500 MTurkers) accurately tracked the frequency with which men (N = 516) knocked out similar-sized adversaries (Study 3). Humans were able to directly perceive a man's knockout power because they were attending to cues of a man's body size. Human dominance judgments-which are important across numerous psychological domains, including attractiveness, leadership, and legal decision-making-accurately predict the likelihood with which a potential mate, ally, or rival can incapacitate their adversaries.


Asunto(s)
Tamaño Corporal , Juicio , Predominio Social , Humanos , Masculino , Tamaño Corporal/fisiología , Juicio/fisiología , Adulto , Conducta Competitiva/fisiología , Adulto Joven
19.
J Sports Sci Med ; 23(2): 358-365, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38841631

RESUMEN

Mixed-Team-Relay (MTR) triathlon is a novel Olympic discipline whose performance determinants and tactical behaviors have barely been studied. Additionally, a regulatory change has been made to the male and female relay order for the Paris 2024 Olympics. Therefore, this study aimed to determine the performance determinants and race dynamics as a function of competitive level on the new regulated MTR triathlon. Results from 129 national teams, (516 elite triathletes) across five MTR World Triathlon Series and two MTR European Championships in 2022 and 2023, were analyzed. Split times, average speeds, time behind the race leader (gap), partial and finishing positions, pack position as well as the rank positions of every segment, relay leg, and overall race were computed. Decision tree analyses were conducted as a predictive method for the overall results, and correspondence analyses were conducted to examine the relationship between the different relay legs and segments and the finishing positions. The performance of the fourth leg was the most relevant for overall result (30%), as well as the fourth running leg (16%) and the female legs performance (7%). Medallist relay teams were characterized by displaying a differential speed lower than 0.5 and 0.83 km/h, respectively, from the best-ranking athletes in the Legs 1 and 4. Furthermore, staying in the front pack after the second swimming leg showed a great relationship with achieving a medal position. New MTR triathlon rules shift race dynamics, emphasizing individual efforts in cycling and swimming, while maintaining the crucial importance of running.


Asunto(s)
Rendimiento Atlético , Ciclismo , Conducta Competitiva , Carrera , Natación , Humanos , Rendimiento Atlético/fisiología , Masculino , Ciclismo/fisiología , Femenino , Carrera/fisiología , Natación/fisiología , Conducta Competitiva/fisiología , Deportes de Equipo
20.
J Biol Dyn ; 18(1): 2365792, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38860975

RESUMEN

This paper concerns the invasion dynamics of the lattice pioneer-climax competition model with parameter regions in which the system is non-monotone. We estimate the spreading speeds and establish appropriate conditions under which the spreading speeds are linearly selected. Moreover, the existence of travelling waves is determined by constructing suitable upper and lower solutions. It shows that the spreading speed coincides with the minimum wave speed of travelling waves if the diffusion rate of the invasive species is larger or equal to that of the native species. Our results are new to estimate the spreading speed of non-monotone lattice pioneer-climax systems, and the techniques developed in this work can be used to study the invasion dynamics of the pioneer-climax system with interaction delays, which could extend the results in the literature. The analysis replies on the construction of auxiliary systems, upper and lower solutions, and the monotone dynamical system approach.


Asunto(s)
Modelos Biológicos , Especies Introducidas , Conducta Competitiva/fisiología , Dinámica Poblacional
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