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Determinants of 1500-m Front-Crawl Swimming Performance in Triathletes: Influence of Physiological and Biomechanical Variables

Óscar López-Belmonte, Jesús J. Ruiz-Navarro, Ana Gay, Francisco Cuenca-Fernández, Roberto Cejuela, and Raúl Arellano

Purpose: To analyze the associations between physiological and biomechanical variables with the FINA (International Swimming Federation) points (ie, swimming performance) obtained in 1500-m front-crawl swimming to determine whether these variables can be used to explain triathletes’ FINA points. Methods: Fourteen world-class, international and national triathletes (10 male: 23.24 [3.70] y and 4 female: 23.36 [3.76] y) performed a 1500-m front-crawl swimming test in a short-course pool. Heart rate (HR), oxygen uptake ( V ˙ O 2 ), and blood lactate concentrations were obtained before and after the test. HR was also measured during the effort. Highest V ˙ O 2 value ( V ˙ O 2 peak ) was estimated by extrapolation. Clean swimming speed, turn performance, stroke rate, stroke length, and stroke index (SI) were obtained by video analysis. Results: Average 1500-m performance times were 1088 (45) seconds and 1144 (31) seconds for males and females, respectively. HR after the effort, V ˙ O 2 peak , aerobic contributions, total energy expenditure, energy cost, and turn performance presented moderate negative associations with swimming performance (r ≈ .5). In contrast, respiratory exchange ratio, anaerobic alactic contribution, clean swimming speed, stroke length, and SI were positively related, with clean swimming speed and SI having a strong large association (r ≈ .7). A multiple stepwise regression model determined that 71% of the variance in FINA points was explained by SI and total energy expenditure, being predictors in 1500-m front-crawl swimming. Conclusions: Swimming performance in triathletes was determined by the athletes’ energy demands and biomechanical variables. Thus, coaches should develop specific technique skills to improve triathletes’ swimming efficiency.

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The Fine-Tuning Approach for Training Monitoring

Daniel Boullosa, João Gustavo Claudino, Jaime Fernandez-Fernandez, Daniel Bok, Irineu Loturco, Matthew Stults-Kolehmainen, Juan García-López, and Carl Foster

Purpose: Monitoring is a fundamental part of the training process to guarantee that the programmed training loads are executed by athletes and result in the intended adaptations and enhanced performance. A number of monitoring tools have emerged during the last century in sport. These tools capture different facets (eg, psychophysiological, physical, biomechanical) of acute training bouts and chronic adaptations while presenting specific advantages and limitations. Therefore, there is a need to identify what tools are more efficient in each sport context for better monitoring of training process. Methods and Results: We present and discuss the fine-tuning approach for training monitoring, which consists of identifying and combining the best monitoring tools with experts’ knowledge in different sport settings, designed to improve (1) the control of actual training loads and (2) understanding of athletes’ training adaptations. Instead of using single-tool approaches or merely subjective decision making, the identification of the best combination of monitoring tools to assist experts’ decisions in each specific context (ie, triangulation) is necessary to better understand the link between acute and chronic adaptations and their impact on health and performance. Future studies should elaborate on the identification of the best combination of monitoring tools for each specific sport setting. Conclusion: The fine-tuning monitoring approach requires the simultaneous use of several valid and practical tools, instead of a single tool, to improve the effectiveness of monitoring practices when added to experts’ knowledge.

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Erratum. Competitive Cross-Country Skiers Have Longer Time to Exhaustion Than Recreational Cross-Country Skiers During Intermittent Work Intervals Normalized to Their Maximal Aerobic Power

International Journal of Sports Physiology and Performance

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Erratum. Inconsistent Effect of Psychometric-Scale Familiarization on the Relationship Between Ratings of Perceived Exertion and External Load Measures in Elite Youth Soccer Players

International Journal of Sports Physiology and Performance

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Handedness, Bilateral, and Interdigit Strength Asymmetries in Male Climbers

Cameron Hartley, Nicola Taylor, Joel Chidley, Jiří Baláš, and Dave Giles

Purpose: To determine whether there are bilateral and interdigit differences in the maximal force production of experienced climbers and whether these differences are mediated by ability level or preferred style of climbing. Methods: Thirty-six male climbers (age 30 [9.4] y) took part in a single-session trial to test their maximal force production on both hands. The tests included a one-arm maximal isometric finger flexor strength test (MIFS) and a one-arm individual MIFS. Bilateral differences were analyzed by strongest hand (defined as the hand that produced the highest MIFS value) and dominance (defined as the writing hand). Results: A pairwise t test found that MIFS was significantly greater for the strongest hand (mean difference = 4.1%, 95% CI, −0.052 to 0.029, P < .001), with handedness explaining 89% of the variation. A 2-way mixed-model analysis of variance determined that there were no interactions between preferred style (bouldering or sport climbing) and MIFS or between ability level (advanced or elite) and MIFS. Conclusions: Climbers have significant finger flexor strength bilateral asymmetries between their strongest and weakest hand. Moreover, when dominance is controlled, this difference in strength is present, with the dominant hand producing more force. Neither preferred style of climbing nor the ability level of the climbers could explain these asymmetries. As such, practitioners should consider regularly monitoring unilateral strength, aiming to minimize the likelihood of large bilateral asymmetry occurring.

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Changes in the Force–Velocity Relationship of Knee Muscles After Anterior Cruciate Ligament Reconstruction Using the Isokinetic 2-Point Model

Joffrey Drigny, Anaelle Calmès, Emmanuel Reboursière, Christophe Hulet, and Antoine Gauthier

Purpose: After anterior cruciate ligament reconstruction (ACL-R), knee muscle strength symmetry is used as part of the return-to-sport criteria. However, little is known about the changes in the force–velocity (F–V) relationship, which could affect athletic performance. This study investigated the F–V relationship of knee muscles at 4 and 8 months after ACL-R, using the 2-point method tested by isokinetic dynamometry. Methods: A total of 103 physically trained individuals (24.6 [9.3] y, 59.2% male) who underwent primary ACL-R were included. Demographic information and surgery characteristics were collected at 6 weeks postoperatively. Isokinetic knee flexors’ and extensors’ peak torques were measured at 60° and 240° per second in the concentric mode at 4 and 8 months postoperative. Peak torques and angular velocities were converted to force and linear velocity for calculating maximum isometric force (F0) and the slope of the regression line (F–V slope). Results: At 4 and 8 months postoperative, F0 was significantly lower and F–V slope was significantly less steep (less negative) on the operated leg compared with the nonoperated leg for knee extensors (P < .001) and flexors (P < .001–.002). The limb symmetry index calculated using F0 was lower than the limb symmetry indexes assessed at 60° and 240° per second, especially for knee flexors (P < .001). The use of patellar tendon grafts was associated with lower F0 and a less steep F–V slope compared with hamstring tendon grafts (P < .010). Conclusion: The isokinetic 2-point model assessing the F–V relationship provides additional and relevant insight for evaluating knee muscle strength after ACL-R.

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Interference Effects of Different Resistance-Training Protocols on Rowing Ergometer Performance: A Study on Semiprofessional Rowers

Danica Janicijevic, Mauricio Elías Leandro Quidel-Catrilelbún, Andrés Baena-Raya, and Amador García-Ramos

Purpose: To evaluate the interference effects of various resistance-training (RT) protocols on rowing ergometer performance. Methods: Fourteen semiprofessional male rowers randomly completed 5 protocols in separate sessions: (1) control—no RT session was performed, (2) upper-body high-fatigue—4 sets to failure during the bench pull exercise, (3) upper-body low-fatigue—4 sets of 6 repetitions during the bench pull exercise, (4) lower-body high-fatigue—4 sets to failure during the leg-press exercise, and (5) lower-body low-fatigue—4 sets of 6 repetitions during the leg-press exercise. All sets were performed against the 12-repetition-maximum load with 2 minutes of interset rest. Following the completion of the protocols, subjects performed an all-out 1000-m rowing ergometer test. Results: Compared with the control condition, rowing ergometer performance was not significantly affected after the low-fatigue RT protocols (upper body: P ≥ .487; Δ = 0.0%–0.2%; lower body: P ≥ .200; Δ = −0.2%–0.5%), while it significantly declined following high-fatigue RT protocols (upper body: P ≤ .001; Δ = 1.0%–2.0%; lower body: P ≤ .002; Δ = 2.1%–2.5%). The average heart rate was significantly lower for the control condition compared with all RT protocols (P ≤ .043; Δ = 1.0%–1.5%). Conclusions: To minimize interference on rowing performance, coaches should prioritize the level of effort in RT protocols over specific exercises, specifically avoiding high-fatigue protocols that lead to failure before rowing practice.

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On-Field Methodological Approach to Monitor the Menstrual Cycle and Hormonal Phases in Elite Female Athletes

Marine Dupuit, Alice Meignié, Tom Chassard, Ludivine Blanquet, Julien LeHeran, Thomas Delaunay, Elise Bernardeau, Jean-François Toussaint, Martine Duclos, and Juliana Antero

Objectives: Currently, there are no guidelines for implementing the monitoring of menstrual status, including the natural menstrual cycle (NC) or oral contraception (OC), in a sport setting. We aimed to provide a feasible, on-field methodological approach for monitoring NC and OC in female athletes. Methods: We developed a smartphone app with daily questionnaires to monitor both NC and OC phases in 19 elite female soccer players (23.7 [4.4] y) over 7 months. Adherence and compliance were evaluated. The NC and OC phases were based on calendar data to establish an individual menstrual profile for each athlete. Results: The initial questionnaire revealed that the vast majority of female players (80%) were interested in monitoring their menstrual status. The online monitoring yielded high athlete adherence (87.0% [14.2%]) with a slight decrease over the winter break and at the end of the championship, which necessitated adaptations to promote compliance. Monitoring identified the specific menstrual pattern of each athlete and highlighted large interindividual variability. Conclusion: This study assesses, for the first time, the interest of female players in monitoring their menstrual status. It provides a new methodological approach, as well as guidelines for optimizing on-field monitoring. It also anticipates some obstacles sport staff may encounter when trying to implement such follow-up. It is essential to better understand the menstrual profile of athletes and determine its potential impacts on well-being and performance.

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Volume 18 (2023): Issue 9 (Sep 2023): Special Issue: Rugby World Cup 2023—Physiology and Performance Research

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Inconsistent Effect of Psychometric-Scale Familiarization on the Relationship Between Ratings of Perceived Exertion and External Load Measures in Elite Youth Soccer Players

Efthymios Kyprianou, Lorenzo Lolli, Matthew Weston, and Warren Gregson

Objectives: To examine the moderating effect of familiarization on the relationship between external load and ratings of perceived exertion (RPEs) in elite youth soccer players. Methods: Thirty-five elite male youth soccer players were monitored over a 31-week period. Players had no previous experience using the centiMax scale (arbitrary units [AU]). The final sample included familiarized (blackness test; n = 20) and nonfamiliarized players (n = 15) with the Borg centiMax scale. Players recorded a global RPE and differential RPEs (dRPE) for breathlessness (RPE-B) and leg-muscle exertion (RPE-L) 15 to 30 minutes following training sessions and competitive matches. Separate multivariable-adjusted random-effects generalized additive models with restricted maximum likelihood quantified familiarization versus no-familiarization differences in actual perceived exertion score (in AU) by number of accelerations, decelerations, and high-speed running distance (in meters) as predictor variables, respectively. Results: Players improved their blackness test score from 39% to 78%. For explorations by number of accelerations, familiarization effects were not practically relevant for the RPE and RPE-B variables. The width and sign of the effects for the RPE-L variable at 30 efforts of 10 AU (95% CI, 4–16 AU) suggested that scores were lower for players who underwent familiarization versus players who did not. Familiarization effects were not practically relevant for any RPE variable irrespective of the number of deceleration efforts and high-speed running distance covered. Conclusion: Improved performance on the blackness test did not have a moderating effect on the relationship between proxy measures of external load and RPEs.