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Greater Psychophysiological Intensities in Conditioned Games May Impair Technical Performance: An Exploratory Study in Youth Male Soccer Players

Filipe Manuel Clemente

Purpose: The aim of this study was 2-fold: (1) to examine the relationships between psychophysiological responses and locomotor demands with variations in technical performance during 2v2 and 4v4 conditioned games and (2) to compare psychophysiological and locomotor responses among players exhibiting higher and lower technical performance levels during the conditioned games. Methods : Twenty-four male youth soccer players (16.3 ± 0.8 y old) participating at the trained/developmental level underwent monitoring for psychophysiological responses (including heart rate, rating of perceived exertion, and visual analog scale), locomotor demands (such as distance covered), and technical performance variables (including successful and unsuccessful passes and shots, as well as lost balls) across 2v2 and 4v4 formats. These formats were applied 4 times within a single session and were replicated twice over 2 weeks. Results: Large correlations between the number of lost balls per minute and mean heart rate were found in both the 2v2 and 4v4 games (r = .586 and r = .665, respectively). Successful shots were inversely and largely correlated with mean heart rate (r = −.518) in 4v4 games. The number of interceptions per minute was inversely and significantly correlated with the visual analog scale in 2v2 and 4v4 games (r = −.455 and r = −.710, respectively). The frequency of lost balls was significantly higher among players who attained a higher mean heart rate (2v2: +42.9%, P = .031, d = −0.965; 4v4: +57.1%, P < .001, d = −2.072). Conclusions: Coaches should be aware that highly psychophysiologically demanding scenarios may significantly impair technical performance. Therefore, prioritizing technical performance by deliberately adjusting the intensity should be considered.

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Volume 19 (2024): Issue 4 (Apr 2024)

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The Influence of High-Intensity Work on the Record Power Profile of Under-23, Pro Team, and World Tour Cyclists

Peter Leo, Manuel Mateo-March, Andrea Giorgi, Xabier Muriel, Alejandro Javaloyes, David Barranco-Gil, Jesús G. Pallarés, Alejandro Lucia, Iñigo Mujika, and Pedro L. Valenzuela

Background: Durability (ie, the ability to attenuate the decline in performance after accumulated work) has been identified as a performance determinant in elite cyclists. The aim of the present study was to compare durability in elite cyclists of various performance levels, particularly after high-intensity work, referred to as “high-intensity durability.” Methods: Forty-nine (N = 49) male road cyclists were categorized as either under 23 years of age (U23) (N = 11), Pro Team (N = 13), or World Tour (N = 24). The participants’ critical power (CP) was assessed during the preseason. Thereafter, the participants’ maximum mean power (MMP) values were determined for efforts of different durations (from 5 s to 30 min) after different levels of accumulated work above CP (from 0 to 7.5 kJ·kg−1). Results: U23 cyclists showed a significant reduction of all relative MMP values for durations ≥1 minute after ≥5 kJ·kg−1 above CP compared with the “fresh” state (0 kJ·kg−1), whereas in Pro Team and World Tour cyclists, a significant reduction was not observed until 7.5 kJ·kg−1 above CP. In the “fresh” state, both Pro Team and particularly World Tour cyclists attained higher MMP values for efforts ≥10 minutes than U23 riders. However, more differences emerged with greater previous work levels, and indeed after 7.5 kJ·kg−1 above CP World Tour cyclists attained higher MMP values than both U23 and Pro Team cyclists for most efforts (≥30 s). Conclusion: Pro Team and particularly World Tour cyclists tolerate greater levels of accumulated work at high intensity, which might support the importance of high-intensity durability for performance.

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Cadence Paradox in Cycling—Part 1: Maximal Lactate Steady State and Carbohydrate Utilization Dependent on Cycling Cadence

Ralph Beneke, Marisa Granseyer, and Renate M. Leithäuser

Purpose: To assess (1) whether and how a higher maximal lactate steady state (MLSS) at higher cycling cadence (RPM) comes along with higher absolute and/or fractional carbohydrate combustion (CHOMLSS), respectively, and (2) whether there is an interrelation between potential RPM-dependent MLSS effects and the maximally achievable RPM (RPMMAX). Methods: Twelve healthy males performed incremental load tests to determine peak power, peak oxygen uptake, and 30-minute MLSS tests at 50 and 100 per minute, respectively, to assess RPM-dependent MLSS, corresponding power output, CHOMLSS responses, and 6-second sprints to measure RPMMAX. Results: Peak power, peak carbon dioxide production, and power output at MLSS were lower (P = .000, ω2 = 0.922; P = .044, ω2 > 0.275; and P = .016, ω2 = 0.373) at 100 per minute than at 50 per minute. With 6.0 (1.5) versus 3.8 (1.2) mmol·L−1, MLSS was higher (P = .000, ω2 = 0.771) at 100 per minute than at 50 per minute. No corresponding RPM-dependent differences were found in oxygen uptake at MLSS, carbon dioxide production at MLSS, respiratory exchange ratio at MLSS, CHOMLSS, or fraction of oxygen uptake used for CHO at MLSS, respectively. There was no correlation between the RPM-dependent difference in MLSS and RPMMAX. Conclusions: The present study extends the previous finding of a consistently higher MLSS at higher RPM by indicating (1) that at fully established MLSS conditions, respiration and CHOMLSS management do not differ significantly between 100 per minute and 50 per minute, and (2) that linear correlation models did not identify linear interdependencies between RPM-dependent MLSS conditions and RPMMAX.

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Erratum. Addressing Circadian Disruptions in Visually Impaired Paralympic Athletes

International Journal of Sports Physiology and Performance

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Influence of Amputation on Kinetic Chain Musculature Activity During Basic and Modified Core Exercises

Kaiqi Liu, Linhong Ji, and Yijia Lu

Purpose: Core strength is vital for athletic performance, and many more exercises that involve the kinetic chain have been designed for able-bodied athletes. Disabilities that impair the kinetic chain can reduce the effectiveness of strength training. However, the impact of amputation on core strength training of people with disabilities and its underlying mechanism remains unclear. This study aimed to evaluate the muscle activation patterns and levels in athletes with amputation during 4 basic and modified weight-bearing core strength-training exercises. Methods: Fifteen elite athletes with unilateral amputation (170.6 [7.3] cm; 63.9 [11.9] kg; 25.9 [5.3] y) volunteered for this study. Surface electromyography was used to measure the muscle activity mainly in the lumbopelvic–hip complex-stabilizing muscles during 4 kinetic chain trunk exercises with and without modifications. Results: The significance level was set at α = .05. The results showed a significant difference in muscle activation between different body sides (P < .05). Specifically, amputation on the support position resulted in a diagonal pattern of muscle activation, and amputation on the free distal segments resulted in a unilateral dominant pattern with higher activation in muscles on the nonamputated side (P < .05). Modifications led to significant decreases in muscle activation asymmetry index (P < .05). Conclusions: Amputation caused muscle activation asymmetry and 2 activation patterns. Modifications by enhancing proximal stability and adjusting distal loading effectively reduced the asymmetry of muscle activation. Coaches and clinicians can use these results to tailor exercises for athletes with disabilities in training and rehabilitation.

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Strategies to Involve End Users in Sport-Science Research

Christopher J. Stevens and Christian Swann

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Investigating the Relevance of Maximal Speed and Acceleration in Varsity-Level Female Ice Hockey Players

Alexander S.D. Gamble, Kyle M.A. Thompson, Jessica L. Bigg, Christopher Pignanelli, Lawrence L. Spriet, and Jamie F. Burr

Purpose: To characterize and compare female ice hockey players’ peak skating speed and acceleration ability during linear sprints and gameplay. We also sought to quantify the time spent at various speeds and the frequency of accelerations at different thresholds during games. Methods: Seventeen varsity-level female ice hockey players (20 [1.4] y, 68.9 [4.9] kg, 167.6 [4.7] cm) participated in an on-ice practice session (performing 3 × 40-m linear sprints) and 4 regular-season games while being monitored using a local positioning system. Speed and acceleration were recorded from the sprint and within-game monitoring. Time on ice spent in relative skating speed zones and the frequency of accelerations at different intensities were recorded. Results: Players’ greatest peak speeds (29.5 [1.3] vs 28.3 [1.1] km/h) and accelerations (4.39 [0.48] vs 3.34 [0.36] m/s2) reached during gameplay were higher than those reached in linear sprinting (both P < .01). Peak in-game values were moderately predicted by linear sprint values for speed (r = .69, P < .01) but not for acceleration (r < .01, P = .95). Players spent little time at near-peak linear sprint speeds (≥80% [22.7 km/h], ∼3% time on ice; ≥90% [25.5 km/h], <1% of time on ice) during gameplay. However, 26% to 35% of accelerations recorded during the 4 games were ≥90% of linear sprint acceleration. Conclusions: Although skating speed may be advantageous in specific game situations, our results suggest that players spend little time at near-maximal speeds while accelerating frequently during games. This warrants further investigation of direction changes, skating transitions, repeated sprints, and other determinant variables potentially related to on-ice success and the implementation of training strategies to improve repeated acceleration or qualities beyond maximal skating speed.

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Countermovement-Jump and Pull-Up Performance Before and After a Swimming Race in Preparatory and Competitive Phases of a Swimming Season

José M. Gonzalez-Rave, Vincenzo Sorgente, Aaron Agudo-Ortega, Víctor Rodrigo-Carranza, Stelios Psycharakis, and Anthony P. Turner

Purpose: Monitoring performance athletes’ training responses can be efficiently completed at competitive events. This study aimed to explore the changes in swimming, countermovement-jump (CMJ), and pull-up (PU) performance following training across a competitive phase, as well as immediately before and after each race. Methods: Fourteen well-trained male sprint/middle-distance swimmers (height 179 [7] cm, mass 70 [8] kg, age 18 [2] y), from 3 regional training groups, completed CMJ and PU tests before and after the national competitions in October and May, when race performance was also assessed. Results: Swimming race performance was significantly improved from before the national competitions in October to after the national competitions in May (1.8% [3.2%], P = .044, d = 0.60, moderate effect). Although there were no significant changes in PU velocity, CMJ performance significantly improved from before the national competitions in October to after the national competitions in May (mean difference 2.29 cm, P = .004, d = 3.52) and showed before-to-after race decreases (mean difference −1.64 cm, P = .04, d = 2.28). Conclusion: Swimming performance and CMJ performance improved as the season progressed, although these improvements were not directly correlated. PU performance did not appear to be sensitive to training or race-induced fatigue, in contrast to CMJ, in this group of male swimmers.

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The Quantification of Physical Performance and Internal Training Load in Youth Male Soccer Players During Preseason

Diogo V. Martinho, André Rebelo, Adam Field, Alex S. Ribeiro, Filipa Pereira, Bruno Bizarro, João Ribeiro, Silvano M. Len, Élvio R. Gouveia, and Hugo Sarmento

Purpose: The monitoring of training loads and quantification of physical performance are common practices in youth soccer academies to support coaches in prescribing and programming training for individuals. The interaction between training load and physical performance is unknown during a preseason period in youth soccer players. The current study assessed changes in training load and physical assessments across a 4-week preseason period. The relationship between physical performance and match playing time in youth male soccer players was also investigated. Methods: The training loads of 25 professional youth academy male soccer players were monitored throughout a 4-week preseason period. Assessments of power, agility, speed, and aerobic capacity were undertaken in the first training session. Session ratings of perceived exertion (sRPE) and well-being questionnaires were collected during all training sessions and preseason matches. Playing time during subsequent competitive matches was recorded. Results: T test and 30-m-sprint assessments, conducted on the first day of preseason, were predictors of sRPE throughout preseason (t test χ2/df = 2.895, poor adjustment; 30-m sprint χ2/df = 1.608, good adjustment). YoYo Test performance was related with changes in perceived fatigue (χ2/df = 0.534, very good adjustment). Faster players reported higher values of sRPE, and players with higher aerobic capacity reported higher levels of fatigue across preseason. Well-being, perceived fatigue and soreness, and sRPE decreased across preseason. Greater match durations were related to higher levels of fatigue during preseason (P < .05). Conclusion: The current study highlights the relationship between training load, physical assessments, and playing time. Coaches and practitioners can use physical test data at the start of preseason as an indication of players that report higher sRPE, perceived fatigue, and reduced well-being across preseason, supporting decisions around individualized training prescriptions.