Sports Health-A Multidisciplinary Approach最新文献

Background: Australian Rules Football athletes complete long preseasons, yet injuries occur frequently at early stages of the competitive season. Little is known about the high-speed running (HSR) prescription during a preseason or whether players are adequately prepared for competition. This study described absolute and relative preseason and in-season HSR demands of 2 professional Australian football teams.

Hypothesis: HSR and sprinting volumes are significantly lower in elite Australian Rules football athletes during in-season compared with preseason.

Study design: Cohort study.

Level of evidence: Level 3.

Methods: During the 2019 season, HSR volume was collected for 2 professional Australian football teams (n = 55). Individual maximum speeds (V_max) were captured to calculate relative running speed thresholds, as reported in 5% increments from 70%V_max to 100%V_max.

Results: Weekly volume of running above 70%V_max (P = 0.01; r = 0.56) and 80%V_max (P = 0.01; r = 0.58) was significantly greater in the preseason than the in-season. The weekly volume completed above 90%V_max was not significantly greater in the preseason than the in-season (P = 0.10; r = 0.22). Individual variation in the distance completed at specific percentages of V_max expressed as a coefficient of variation was reported as 51% at 71% to 80%V_max, 39% at 81% to 90%V_max, and 41% at 91% to 100%V_max.

Conclusion: The volume of HSR completed by athletes is far greater in the initial 4 weeks of the preseason than in any other point in preseason or competitive phases. At the individual level, there is substantial variation in the distance covered. This supports the concept of a heavily individualized approach to high-speed prescription and monitoring.

Clinical relevance: Practitioners should carefully consider individual variation regarding sprinting volume during both preseason and in-season when prescribing and monitoring training to improve on-field performance and reduce the risk of injury.

Background: Many questions persist regarding the relationship between training load and injuries in volleyball, as well as the best method for calculating acute:chronic workload ratio (ACWR). This study aimed to investigate the relationship between different metrics of training load and risk of injury in male professional volleyball players.

Hypothesis: ACWR, as a training load measure, is useful for identifying injury risk in volleyball players, regardless of calculation method.

Study design: Longitudinal, prospective, and observational design conducted over 3 seasons of professional male volleyball.

Level of evidence: Level 3.

Methods: The study included 43 male volleyball players. Internal training load was quantified using the Session Rating of Perceived Exertion. From daily training load values, absolute measures and relative measures were computed. For relative measures, 7 days were employed for acute training load, and 21 and 28 days for chronic training load. A distinction was made between coupled calculation and uncoupled calculation. Injuries were documented using the Injury Surveillance Form proposed by the International Volleyball Federation.

Results: ACWR calculated in a coupled manner and by a rolling average demonstrated higher injury risks when analyzing the complete periods (odds ratio [OR] ACWR 7:28 = 2.040; ACWR 7:21 = 1.980) and competitive period (OR ACWR 7:28 = 2.044; ACWR 7:21 = 2.087). In contrast, during the preseason, the coupled exponential averages were more sensitive to the risk of injury (OR ACWR 7:28 = 4.370; ACWR 7.504).

Conclusion: Both measures using rolling averages and those calculated from exponential averages can be employed to identify the risk of injuries in volleyball athletes.

Clinical relevance: The findings of this study can be useful to coaching staff, fitness trainers, and healthcare professionals involved in the challenge of reducing the risk of injury in volleyball athletes. The need for continuous monitoring and real-time adjustments of training load is emphasized.

Background: Monitoring training load has the potential to improve sport performance and reduce injuries in athletes. This study examined training load and its association with wellness in artistic gymnastics.

Hypotheses: Training load and changes in training load (acute:chronic workload ratio [ACWR]) vary throughout 1 season; wellness is inversely correlated with training load and ACWR.

Study design: Prospective case series.

Level of evidence: Level 3.

Methods: A total of 30 female collegiate gymnasts from 4 Division I National Collegiate Athletic Association teams participated (mean age, 20 ± 2 years). During 4 months, before daily training, wellness surveys assessed sleep, energy, soreness, and mood (1-10; higher = better). After daily training, training load surveys assessed training duration per event (warm-up, vault, bars, beam, floor, strength and conditioning) and session rating of perceived exertion (RPE; 1-10; 10 = hardest) per event. Coaches reported technical complexity of training per event (1-4; 4 = hardest). Training load was calculated as [duration] × [RPE] × [technical complexity]. ACWR represented a ratio between acute [1-week] and chronic [4-week rolling average] training loads.

Results: ACWR and weekly training load fluctuated throughout the season (ACWR mean weekly range: 0.68-1.11; training load mean weekly range: 2073-6193 arbitrary units). ACWR and weekly training loads were trichotomized into low, medium, and high groups; positive correlations were observed between each wellness variable and ACWR (P < 0.01) and between each wellness variable and weekly training load (P < 0.01).

Conclusion: Our novel training load monitoring framework for women's college gymnastics enabled us to characterize training load and its relationship with wellness throughout 1 season. This method should be explored in gymnasts across various ages and competitive levels.

Clinical relevance: This study proposes a framework and the initial findings of monitoring training load and wellness in collegiate women's gymnastics.

Background: Monitoring training load and competition load is crucial for evaluating and improving athlete performance. This study proposes an applied approach to characterize and classify the training task specificity in relation to competition in a top-level rink hockey team, considering external and internal load from training tasks and competition.

Hypothesis: Training tasks and game demands have significant dose-response differences, and exercises can be classified successfully based on their physiological and biomechanical demands.

Study design: Cross-sectional study.

Level of evidence: Level 5.

Methods: Ten elite-level male rink hockey players participated in this study. Players were monitored on 6 different task categories during 8 training sessions and 2 official games. A linear mixed model with random intercepts was used to compare training tasks and competition load, accounting for individual repeated measures. A 2-step cluster analysis was performed to classify the training tasks and games based on physiological and biomechanical load, employing log-likelihood as the distance measure and Schwartz's Bayesian criterion.

Results: Average heartrate, maximum heartrate, and high-speed skating (18.1-30 km/h) were the best physiological load predictors, while the most effective biomechanical load predictors were impacts [8-10] g(n), decelerations [-10 to -3]m/s²(n), and accelerations [3-10]m/s²(n). Different physiological and biomechanical responses were verified between training tasks and match demands. A 4-quadrant efforts assessment for each task category revealed that training tasks used by the team in the analysis presented lower biomechanical and physiological load demands than competition.

Conclusion: Training tasks failed to adequately replicate the specific demands of competition, especially regarding high mechanical stress, such as the absence of high-intensity impacts and decelerations.

Clinical relevance: This method of classification of training tasks may allow coaches to understand further the specificity and contribution of each task to competition demands, consequently improving the capacity of load management and the preparedness and readiness of players for competition.

Background: This study aimed to compare acceleration and deceleration demands of intercounty Camogie players, and differences across playing positions and halves of play.

Hypothesis: The middle 3 positions will have greatest accelerations and decelerations variables across match play and halves of play.

Study design: Nonrandomized, repeated measures design.

Level of evidence: Level 4.

Methods: Global positioning systems (GPS) (10 Hz) collected data from 28 participants during 18 competitive matches across 2 seasons; 206 individual player datasets were analyzed.

Results: Half-backs (P < 0.05; effect size [ES], -1.75) and midfielders (P < 0.05; ES, -1.68) covered significantly greater total number of accelerations than full-forwards. In acceleration zone 4, midfielders (P < 0.05; ES, = -1.67) and half forwards covered a significantly greater number than full-forwards (P < 0.01; ES, = -1.41). Midfielders accumulated a significantly greater distance in acceleration zone 4 than full-backs (P < 0.05; ES, = -0.57). Significant decrements were observed between halves in total number of accelerations (P < 0.01; ES, = 0.49), accelerations in zones 1 to 4 (P < 0.01; ES, 0.16-0.43), total distance of accelerations, and acceleration distance in zones 2 to 4 (P < 0.05; ES, 0.25; P < 0.01; ES, 0.45; P < 0.01; ES, 0.38). There were significant decrements in the total number of decelerations (P < 0.01; ES, 0.43), number of decelerations in zones 2 (P < 0.05; ES, 0.25), 3 (P < 0.01; ES, 0.45), and 4 (P < 0.01; ES, 0.38), and total deceleration distance (P < 0.01; ES, 0.16).

Conclusion: Half-backs and midfielders covered significantly greater total number of accelerations than full-forwards. Significant decrements in several acceleration and deceleration variables were observed between halves.

Clinical relevance: Players competing in intercounty Camogie should receive progressive exposure to acceleration and deceleration-based movement demands to prepare players for intercounty Camogie match play.

Background: The aim of this study was to determine the influence of different percentages of blood flow restriction (BFR) and loads on mean propulsive velocity (MPV) and subjective perceived exertion during squat (SQ) and bench press (BP) exercises.

Hypothesis: Higher percentages of BFR will positively affect dependent variables, increasing MPV and reducing perceived exertion.

Study design: Cross-sectional study.

Level of evidence: Level 3.

Methods: Eight healthy young male athletes took part. Two sets of 6 repetitions at 70% 1-repetition maximum (1RM), 2 sets of 4 repetitions at 80% 1RM, and 2 sets of 2 repetitions at 90% 1RM were performed randomly; 5-minute recoveries were applied in all sets. The varying arterial occlusion pressure (AOP) applied randomly was 0% (Control [CON]), 80%, and 100%.

Results: No statistically significant differences in MPV were found during the BP exercise at any percentage of BFR at any percentage 1RM. During the SQ exercise, MPV results showed statistically significant increases of 5.46% (P = 0.04; η_p² = 0.31) between CON and 100% AOP at 90% 1RM. The perceived exertion results for the BP exercise showed statistically significant reductions of -8.66% (P < 0.01; η_p² = 0.06) between CON and 100% AOP at 90% 1RM. During the SQ exercise, the perceived exertion results showed significant reductions of -10.04% (P = 0.04; η_p² = 0.40) between CON and 100% AOP at 80% 1RM; -5.47% (P = 0.02; η_p² = 0.48) between CON and 80% AOP at 90% 1RM; and -11.83% (P < 0.01; η_p² = 0.66) between CON and 100% AOP at 90% 1RM.

Conclusion: BFR percentages ~100% AOP at 90% 1RM improved acutely MPV (only in SQ exercises) and reduced acutely perceived exertion (in both exercises). These findings are important to consider when prescribing resistance training for healthy male athletes.

Background: Maximal sprinting speed (MSS) overexposure is associated with increased risk of injury. This study aimed to describe changes in sprint performance-related factors and hamstring strain injury (HSI) risk factors after a high-volume sprinting session in soccer players.

Hypothesis: A high-volume sprinting session can induce acute changes in several sprint performance-related factors (sprint time and mechanical properties) and HSI risk factors (posterior chain muscle strength, hamstring range of motion, and dynamic lumbo-pelvic control [LPC], measured as changes in anterior pelvic tilt [APT] during maximal speed sprinting).

Study design: Prospective observational case series.

Level of evidence: Level 4.

Methods: Fifteen active male amateur soccer players participated. Changes in sprint performance-related factors and HSI risk factors were examined for 72 hours after high-volume MSS efforts (H-VMSSE) using a soccer-contextualized multifactorial approach. Muscle damage proxy markers (hamstring perceived soreness and creatine kinase) were also examined.

Results: H-VMSSE induced decrements in sprint performance-related factors. Significant reductions in theoretical maximal horizontal velocity (P < 0.01; effect size [ES], -0.71) and performance (P = 0.02; ES, -0.59) were observed for 48 and 72 hours after H-VMSSE. Small but significant reductions in posterior chain muscle force-generating capacity were detected for 48 and 72 hours after H-VMSSE for the nondominant (P < 0.03; ES, -0.60) and dominant (P < 0.04; ES, -0.40) leg. Finally, players exhibited persistent small, albeit nonsignificant (P = 0.06; ES, 0.53), decreases in dynamic LPC (APT increases) for 72 hours after H-VMSSE.

Conclusion: H-VMSSE induced declines in both sprint performance-related factors and HSI risk factors. Sprinting can alter a player's anatomic structure by increasing APT during the maximum speed phase of the sprint.

Clinical relevance: A soccer-contextualized multifactorial approach might allow for the regulation of MSS dosage depending on individual HSI risk factor status, thereby serving as a tailored "vaccine" for sprinting needs.

Context: Today's elite and professional sports tend to feature older, more seasoned athletes, who have longer sporting careers. As advancing age can potentially limit peak performance, balancing training load is necessary to maintain an optimal state of performance and extend their sports career.

Objective: To describe an appropriate training model for extended career athletes.

Data sources: Medline (PubMed), SPORTDiscus, ScienceDirect, Web of Science, and Google Scholar.

Study selection: A search of the literature between January 1, 2015 and November 22, 2023 was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

Study design: Narrative review.

Level of evidence: Level 4.

Data extraction: Data were extracted from studies related to the management of training and performance of athletes with extended and long careers.

Results: A total of 21 articles related to extended careers were found. Key themes from these papers included: expertise, biological maturation, and specificity; epidemiology and health; athlete monitoring; strength training; load management and detraining; success management.

Conclusion: A training model for extended career athletes should balance the deleterious effects of age with the athletes' knowledge of, and expertise within, the sport. Designing specific training that accommodates previous injuries, training load intolerances, and caters for quality of life after retirement should be key considerations. Load management strategies for athletes with extended careers should include strength training adaptations to minimize pain, load-response monitoring, a broad range of movement, recovery and intensity activities, and the avoidance of large training load peaks and periods of inactivity.

Background: Women's artistic gymnastics (WAG) is a complex aesthetic sport in which athletes start at a young age and are exposed to high loads during their careers. Little is known about the external and internal training load characteristics among elite young gymnasts.

Hypothesis: High training loads, with variations over the weeks, are expected. There is a relationship between external and internal load variables.

Study design: Cohort study.

Level of evidence: Level 3.

Methods: Seven elite-level Brazilian youth artistic gymnasts (age, 11.3 ± 0.4 years; mass, 33.0 ± 7.0 kg; height, 137.7 ± 10.6 cm; experience, 4.0 ± 1.2 years) participated in this study. Five nonconsecutive microcycles were monitored. Both external and internal training loads were quantified by counting the number of elements in video recordings of training sessions and by the session rating of perceived exertion method.

Results: A total of 168 individual training sessions were monitored. The microcycle that succeeded the main competition showed a significantly lower training load than ≥3 of the other 4 microcycles for all training load variables, except for vault elements, of which microcycle 4 was inferior only to the microcycle before the competition. Significant correlations were found between weekly internal training load and the total of elements and elements performed on uneven bars.

Conclusion: Youth women's artistic gymnasts present fluctuations in external and internal training load variables over the weeks close to a major competition. Training load management in this sport must consider the specificity of each apparatus, as they have different demands and training load behaviors.

Clinical relevance: A better comprehension of external and internal training loads in youth WAG and its apparatuses can benefit coaches and support staff and provide more information to overcome the challenge of training load management in gymnastics.

Context: Athletes often face the dual challenge of high training loads with insufficient time to recover. Equally, in any team, sports medicine and performance staff are required to progress training loads in healthy athletes and avoid prolonged reductions in training load in injured athletes. In both cases, the implementation of a well-established psychological technique known as motor imagery (MI) can be used to counteract adverse training adaptations such as excessive fatigue, reduced capacity, diminished performance, and heightened injury susceptibility.

Study design: Narrative overview.

Level of evidence: Level 5.

Results: MI has been shown to enhance performance outcomes in a range of contexts including rehabilitation, skill acquisition, return-to-sport protocols, and strength and conditioning. Specific performance outcomes include reduction of strength loss and muscular atrophy, improved training engagement of injured and/or rehabilitating athletes, promotion of recovery, and development of sport-specific skills/game tactics. To achieve improvements in such outcomes, it is recommended that practitioners consider the following factors when implementing MI: individual skill level (ie, more time may be required for novices to obtain benefits), MI ability (ie, athletes with greater capacity to create vivid and controllable mental images of their performance will likely benefit more from MI training), and the perspective employed (ie, an internal perspective may be more beneficial for increasing neurophysiological activity whereas an external perspective may be better for practicing technique-focused movements).

Conclusion: We provide practical recommendations grounded in established frameworks on how MI can be used to reduce strength loss and fear of reinjury in athletes with acute injury, improve physical qualities in rehabilitating athletes, reduce physical loads in overtrained athletes, and to develop tactical and technical skills in healthy athletes.