Browse

Purpose: To examine the test–retest reliability of countermovement jump (CMJ) and isometric strength testing measures in elite-level under-18 and under-23 academy football players. Methods: A total of 36 players performed 3 maximal CMJs and isometric abductor (IABS), adductor (IADS), and posterior chain (IPCS) strength tests on 2 separate test days using dual force plates (CMJ and IPCS) and a portable strength testing device (IABS and IADS). Relative (intraclass correlation coefficient) and absolute (coefficient of variation, standard error of the measurement, and minimal detectable change [MDC%]) reliabilities for 34 CMJ, 10 IABS, 10 IADS, and 11 IPCS measures were analyzed using between-sessions best, mean, and within-session methods. Results: For all methods, relative reliability was good to excellent for all CMJ and all IADS measures and poor to good for all IABS and IPCS measures. Absolute reliability was good (ie, coefficient of variation < 10%) for 27 (best) and 28 (mean) CMJ variables and for 6 (IABS and IADS) and 2 (IPCS) isometric measures. Commonly used CMJ measures (jump height, eccentric duration, and flight-time:contraction-time ratio) had good to excellent relative reliability and an MDC% range of 14.6% to 23.7%. Likewise, commonly used isometric peak force measures for IABS, IADS, and IPCS had good to excellent relative reliability and an MDC% range of 22.2% to 26.4%. Conclusions: Commonly used CMJ and isometric strength measures had good test–retest reliability but might be limited by their MDC%. Rate-of-force-development measures (for all isometric tests) and impulse measures (IPCS) are limited by poor relative and absolute reliability and high MDC%. MDC% statistics should be considered in the context of typical responsiveness.

Purpose: To investigate race-management strategies over a longitudinal case study of one of the world’s best female swimmers of the 200-m freestyle to understand if only 1 race-management strategy allowed her to succeed or whether several profiles have been used over the 8 years of analysis. Methods: Different race-management strategies within and between 50-m laps emerged from cluster analysis. To better explain race management, additional characteristics described the level of adversity, the level of competition, the performance outcome, and the type of race. Results: Two strategies of race management between laps have been used, and both allowed her to succeed in her career. The first was characterized by a fast start and a greater decrease of the speed between laps, whereas the second exhibited a more stable speed management. When those strategies were examined in relation to the level of competition and the level of adversity, it appeared that the first strategy was used more in international competitions and associated with higher time intervals between the studied swimmer and the direct rivals, while the second one was used more in national competitions and associated with lower time intervals. Conclusions: Findings suggested that this top elite swimmer did not adhere to a single “ideal” race-management strategy. Instead, she demonstrated flexibility and the ability to adapt her race management to contextual factors throughout her career, effectively controlling adversity. This highlights the importance of including adversity analysis in race-management studies.

Purpose: This investigation sought to determine industry perceptions of postgraduate strength and conditioning (S&C) degrees to understand whether graduates are equipped for the demands of sport performance service roles. Methods: Survey data were collected from 111 participants employed as performance staff or in a role that recruits and supervises performance staff. The survey consisted of 3 main sections: (1) perceptions of career-development opportunities in S&C, (2) perception of S&C postgraduate programs, and (3) perceptions of employability in S&C. Exploratory factor analysis was conducted to identify the key factors considered to be of greatest relevance to career progression in S&C. Results: A 2-factor solution was achieved for each of the 3 sections, resulting in 6 total factors. These factors are Academic and Professional Development, Mentorship and Sport Diversity, Student Preparation, Require Greater Emphasis, Testing and Training, and Personal and Professional Growth. Conclusions: Postgraduate S&C programs require a broad range of placement/internship opportunities to (1) provide diverse experiences, (2) allow students to build contacts and develop professional networks, (3) gain exposure to working in high-performance environments and multidisciplinary teams, and (4) access high-quality mentors. Alongside the ability to deliver training and testing, graduates should be equipped with strong organizational and relationship-building skills. Improved graduate capabilities can raise the standards of the profession and result in enhanced service provision to athletes.

Purpose: The first heart-rate (HR) -variability (HRV) -derived threshold based on detrended fluctuation analysis alpha 1 (DFA a1) has shown inconsistent agreement with the gas-exchange threshold (GET). This study examined whether a custom method of computing the first HRV threshold (HRVT₁) based on individual HRV characteristics would improve agreement. Methods: Fourteen participants underwent ramp incremental testing measuring gas-exchange variables and RR intervals. Comparisons were made between the oxygen consumption ${\displaystyle {(\dot{\mathrm{V}}\mathrm{O}}_2)/\mathrm{HR}}$ at the GET versus the ${\dot{\mathrm{V}}\mathrm{O}}_2/\mathrm{HR}$ at the standard DFA a1 = 0.75 (HRVT_1s) or a custom value (HRVT_1c) based on the DFA a1 midway between the maximum seen during the early ramp incremental and 0.5. Results: Mean values for GET ${\dot{\mathrm{V}}\mathrm{O}}_2$ versus HRVT_1s ${\dot{\mathrm{V}}\mathrm{O}}_2$ and GET_HR versus HRVT_1sHR were statistically different (25.4 [3.3] vs 29.8 [6.8] mL·kg⁻¹·min⁻¹, P = .01, d = 0.80; 131 [11] vs 146 [22] beats·min⁻¹, P = .005, d = 0.91). There were no statistical differences when using the HRVT_1c (25.4 [3.3] vs 25.1 [5.7] mL·kg⁻¹·min⁻¹, P = .77, d = 0.08; 131 [11] vs 132 [17] beats·min⁻¹, P = .65, d = 0.12). Equivalence between GET and HRVT_1c ${\dot{\mathrm{V}}\mathrm{O}}_2/\mathrm{HR}$ was also verified. Mean maximal DFA a1 during the early ramp incremental was 1.52 (0.22) with mean HRVT_1c of 1.01 (0.11). Pearson r correlation coefficients were between .67 and .70 for all GET to HRVT₁ comparisons. The second HRV threshold and respiratory compensation point parameters showed agreement and correlations in line with prior studies. Conclusions: The HRVT_1c showed stronger agreement to GET parameters than seen using the HRVT_1s. It is recommended that evaluations of the HRVT₁ consider this approach in determining the HR and ${\dot{\mathrm{V}}\mathrm{O}}_2$ at this threshold.

Purpose: To analyze the evolution of the world ranking in swimming over the last 10 years, with particular attention to the effects of COVID-19 on the different levels of participating athletes. Methods: The top 200 world-ranked entries in all swimming events (50-m pool) were collected from 2013 to 2022. A mathematical model (Gaussian model) was proposed to evaluate the ranking progression for different performance levels (clusters) according to distance, stroke, and gender. The model was applied both with and without the COVID season data. Results: Overall results indicated a general progression in world rankings over the last 10 years, except for the COVID season and the post-Olympic year(s), with peak results in the 2021 postpandemic (Olympic) year. The gender gap in World Aquatics points scoring has shown an increasing gap in favor of males since 2017, reaching 1.5% in 2022. The top 200 positions of world rankings were grouped into 3 different clusters defined by the 23.3%, 66.5%, and 100% of ranked male swimmers (or 31.5%, 72.5%, and 100% for females) and with average World Aquatics scores of 910 (12), 858 (10) and 816 (11) points (907 [13], 847 [11], and 802 [12] for females). The Gaussian model showed a gap averaging ∼21 to ∼36 points between performance curves with or without COVID season data, with larger gaps for female rankings and cluster-3 swimmers. Conclusions: These results suggest that, given the lower relative performance of female swimmers in the different clusters of world rankings, female events may provide an opportunity to enter international-level swimming.

Purpose: This study analyzed the effectiveness of net exchanges (ie, number of times the pairs exchange their zone on the court from the net zone to the back zone or vice versa) in men’s and women’s professional padel depending on the competition phase. Methods: Data were collected from 41 matches, comprising a total of 4829 points, from both the qualifying and the main draws of the World Padel Tour Finland Padel Open tournament. Descriptive analysis (frequency and percentage) and inferential tests (Pearson chi-square [χ ²], Cramer V coefficient [Vc], corrected standardized residuals, and chi-squared automatic interaction detection) were carried out. Results: There were significant differences (P < .05) in net exchanges between the main and qualifying draws, both in men’s (79.6% vs 72.1% for no exchanges) and women’s (62.2% vs 57.6% for no exchanges) padel. Additionally, differences in the likelihood of winning points based on whether the serving pair or the returning pair finished the rally at the net were highlighted. Indeed, finishing rallies at the net for the serving pairs increased the probability of scoring a winning shot (ie, in even-numbered net exchanges), while finishing rallies away from the net (ie, in odd-numbered net exchanges) was more likely to result in errors, for both male and female players and main and qualifying draws. Conclusion: This study provides valuable insights into the strategic behavior of professional padel matches, highlighting the importance of net dominance and its impact on match outcomes, particularly in relation to gender differences and phase of competition.