Managing the Training Process in Elite Sports: From Descriptive to Prescriptive Data Analytics

If You Want to Prevent Hamstring Injuries in Soccer, Run Fast: A Narrative Review about Practical Considerations of Sprint Training

Hamstring strain injuries (HSIs) are one of the most common injuries in sprint-based sports. In soccer, the ability to sprint is key, not only because of its relation to performance but also due to its possible protective effect against HSIs. Although many authors have focused on the "how", "when", and "what" training load should be implemented, there is a lack of practical proposals for sprint training in a high-level professional environment. The objective of this narrative review is, after a deep review of the scientific literature, to present a practical approach for sprint training, trying to answer some of the questions that most strength and conditioning coaches ask themselves when including it in soccer. Once the literature published on this topic was reviewed and combined with the practical experience of the authors, it was concluded that sprint training in soccer, although it presents an obvious need, is not something about which there is methodological unanimity. However, following the practical recommendations from this narrative review, strength and conditioning coaches can have a reference model that serves as a starting point for optimal management of the internal and external training load when they wish to introduce sprint training in the competitive microcycle in professional soccer players, with the aim of reducing HSIs.

Epidemiology, etiology and prevention of injuries in competitive ice speed skating-limited current evidence, multiple future priorities: A scoping review

Long-track and short-track ice speed skating are integral to the Winter Olympics. The state of evidence-based injury prevention in these sports is unclear. Our goals were to summarize the current scientific knowledge, to determine the state of research, and to highlight future research areas for injury prevention in ice speed skating. We conducted a scoping review, searching all injury and injury prevention studies in competitive ice speed skaters. The six-stage Translating Research into Injury Prevention Practice (TRIPP) framework summarized the findings. The systematic search yielded 1109 citations. Nineteen studies were included, and additional searches yielded another 13 studies, but few had high-quality design. TRIPP stage 1 studies (n = 24) found competition injury rates from 2% to 18% of participants with various injury locations and types. Seasonal prevalence of physical complaints was up to 84% (for back pain) in long- and short-track. Ten studies covered information on TRIPP stage 2, with two small etiological studies linking injuries to functional strength deficits (short-track) and training load (long-track). Questionnaire studies identified various perceived risk factors for injuries but lacked further scientific evidence. Most TRIPP stage 3 studies (five out of eight) focused on developing protective measures, while two studies found short-track helmets performed poorly compared to helmets used in other sports. No study evaluated the efficacy, the intervention context, or the effectiveness (TRIPP stages 4-6) of the measures. Scientific knowledge on injury prevention in ice speed skating is limited. Future research should prioritize high-quality studies on injury epidemiology and etiology in the sports.

Within-Subject Principal Component Analysis of External Training Load and Intensity Measures in Youth Soccer Training

ABSTRACT

Marynowicz, J, Lango, M, Horna, D, Kikut, K, Konefał, M, Chmura, P, and Andrzejewski, M. Within-participant principal component analysis of external training load and intensity measures in youth soccer training. J Strength Cond Res 37(12): 2411-2416, 2023-The aim of this study was to identify which combination of external training load (EL) and external intensity (EI) metrics during youth soccer training sessions captured similar or unique information. Data were collected from 18 youth soccer players during an 18-week in-season competition period using a 10-Hz global positioning system, rating of perceived exertion (RPE), and session-RPE (sRPE). External training load measures included total distance (TD, in meters), PlayerLoad (PL, in arbitrary units), high-speed running distance (HSR, in meters), and number of accelerations (ACC, n). All EL metrics were also divided by session duration (minutes) to obtain EI values. A total of 804 training observations were undertaken (43 ± 17 sessions per player). The analysis was performed by use of the principal component analysis technique. The first principal component (PC) captured 49-70% and 68-89% of the total variance in EI and EL, respectively. The findings show that from the 5 EI metrics, most of the information can be explained by either TD per minute or PL per minute, with a loading from 0.87 to 0.98 and from 0.76 to 0.95, respectively. The majority of EL information can be explained by PL (loading: 0.93-0.98), TD (loading: 0.95-0.99), ACC (loading: 0.71-0.91), or sRPE (loading: 0.70-0.93). The second PC for EL metrics is most strongly correlated with HSR, with loadings from 0.53 to 0.84. The results suggest that the majority of the information contained in the EL variables can be captured in 1 PC without losing much information. The findings suggest that stakeholders who intend to provide a fast and holistic view of EL information in a daily training environment should report TD, PL, ACC, or sRPE plus HSR to coaching staff as a metrics that provides additional unique information.

Mechanical Determinants of Sprinting and Change of Direction in Elite Female Field Hockey Players

Profile determination in field hockey is critical to determining athletes' physical strengths and weaknesses, and is key in planning, programming, and monitoring training. This study pursued two primary objectives: (i) to provide descriptive data on sprinting, deceleration, and change of direction (COD) abilities and (ii) to elucidate the mechanical variables that influence sprint and COD performance in elite female field hockey players. Using radar and time-gate technology, we assessed performance and mechanical data from 30 m sprinting, deceleration, and COD tests for 26 elite female hockey players. A machine learning approach identified mechanical variables related to sprint and COD performance. Our findings offer a framework for athlete categorization and the design of performance-enhancing training strategies at the international level. Two pivotal mechanical variables-relative maximum horizontal force (F0) and maximum velocity (Vmax)-predominantly influence the times across all tested distances. However, the force-velocity profile (FVP) and horizontal deceleration do not influence the variance in the COD test outcomes. These insights can guide the design, adjustment, and monitoring of training programs, assisting coaches in decision making to optimize performance and mitigate injury risks for female hockey players.

The Road to Becoming a World Champion in Futsal

PURPOSE

The aim of the current study was to report the training program and monitoring outcomes of the Portuguese national futsal team during the preparation and competition phases of the FIFA Futsal World Cup Lithuania 2021™. For that, the variations in training load and wellness were measured, as well as their relationship.

METHODS

The study followed a retrospective cohort design. For all field training sessions, the volume, exercise structure, and area of play were identified. Player load, session rating of perceived exertion (sRPE), and wellness were collected. Descriptive statistics and Kruskal-Wallis tests were used for comparison purposes. A visualization method was used for load and well-being.

RESULTS

No significant differences were observed in the number of training sessions, session duration, and player load between preparation and competitive periods. sRPE showed significantly higher values in preparation than in competition periods (P < .05, d = 0.86) and significant differences between weeks (P < .05, d = 1.08). Wellness showed a general statistical difference between periods (P < .001, d = 1.28) and weeks (P < .05, d = 1.17). The correlation analysis for the overall period revealed a general linear relationship within variables of training load and wellness (P < .001). Variations occurred for preparation and competition periods. The visualization method through quadrant plots allowed us to understand the adaptation of the team and the players over the specific period under analysis.

CONCLUSIONS

Through this study, it was possible to better understand the training program and monitoring strategies of a high-performance futsal team over a high-level tournament.

Race Analysis and Determination of Stroke Frequency - Stroke Length Combinations during the 50-M Freestyle Event

The aims of this study were to: (1) analyze and compare the stroke kinematics between junior and senior elite male swimmers in every section of the race during the 50-m freestyle event, and; (2) identify stroke frequency (SF)-stroke length (SL) combinations on swim speed independently for junior and senior swimmers in each section of the 50-m freestyle event. Eighty-six junior swimmers (2019) and 95 seniors (2021) competing in the 50-m long course meter LEN Championships were analyzed. The t-test independent samples (p ≤ 0.05) were used to compare juniors and seniors. The SF and SL combinations on swim speed were explored using three-way ANOVAs. Senior swimmers were significantly faster in the 50-m race than juniors (p < 0.001). Speed presented the largest significant difference (p < 0.001) in section S0-15 m (start until the 15^th meter mark) being seniors fastest. Both junior and senior swimmers revealed a significant categorization (p < 0.001) by stroke length and stroke frequency in each race section. It was possible to model several SF-SL combinations for seniors and juniors in each section. The fastest swim speed in each section, for seniors and juniors independently, was achieved by a SF-SL combination that may not be the fastest SF or the longest SL. Coaches and swimmers must be aware that despite the 50-m event being an all-out bout, several SF-SL combinations were observed (independently for juniors and seniors), and they differ between race sections.