Search

Abstract: Glassbrook, DJ, Fuller, JT, Wade, JA, and Doyle, TLA. Not all physical performance tests are related to early season match running performance in professional rugby league. J Strength Cond Res 36(7): 1944-1950, 2022-This study aimed to determine which physical tests correlate with early season running performance. Sixteen professional rugby league players performed the 30-15 intermittent fitness test (IFT), 1.2-km time trial, 1 repetition maximum (RM) barbell back squat, isometric midthigh pull (IMTP), countermovement jump (CMJ), barbell squat jump (SJ), and ballistic bench press throw (BBP). Bivariate Pearson's correlations and linear regression were used to compare physical tests with peak match running intensities recorded by a portable Global Positioning System and represented by peak match velocity and acceleration, as well as peak 1-, 4-, 6-, and 8-minute instantaneous acceleration/deceleration periods of play. Significant (p < 0.05) negative correlations (r = -0.55 to -0.60) were observed between the IFT and relative 1-, 4-, 6-, and 8-minute peaks, and between the relative 1RM back squat and relative 1-, 4-, 6-, and 8-minute peaks. Significant positive correlations (r = 0.52-0.84) were observed between the following physical tests and match performance pairs: IFT and peak acceleration; relative 1RM back squat and peak acceleration; SJ peak power (relative and absolute) and peak acceleration; CMJ peak force (relative and absolute) and peak acceleration; CMJ peak power (relative and absolute) and peak acceleration and 1-, 4-, 6-, and 8-minute peaks; and relative BBP peak power and peak velocity and peak acceleration. The results of this study highlight that not all generic tests of physical qualities are related to peak match running performance and only those with significant correlations are likely to be able to indicate how players may perform during match-play., (Copyright © 2021 National Strength and Conditioning Association.)

Abstract: Wade, JA, Fuller, JT, Devlin, PJ, and Doyle, TLA. Senior and junior rugby league players improve lower-body strength and power differently during a rugby league season. J Strength Cond Res 36(5): 1367-1372, 2022-This investigation evaluated lower-body strength and power changes across a rugby league season in elite junior and senior athletes. Twenty-five senior and 20 junior rugby league players performed an isometric midthigh pull and countermovement jump at 3 time points in a National Rugby League training season (mid-preseason, end-preseason, and in-season). Linear fixed-effects models were used to compare isometric midthigh pull force and countermovement jump power between player experience groups (senior vs. junior) across the season phases (mid-preseason vs. end-preseason vs. and in-season). Cohen's effect sizes (ES) with 95% confidence intervals were calculated for pairwise comparisons. For senior players, absolute and relative strength (ES = 0.38, p < 0.007) and power (ES = 0.64, p < 0.008) increases were observed at end-preseason compared with mid-preseason, but there were no changes in-season (ES = 0.02, p > 0.571). For junior players, strength did not change (ES < 0.01, p > 0.738) and absolute power decreased (ES = 0.29, p < 0.014) at end-preseason compared with mid-preseason; large increases were evident for absolute and relative strength (ES = 1.43, p < 0.001) and power (ES = 0.62, p < 0.001) in-season. This research demonstrates senior and junior rugby league players exhibit unique patterns of improvements in lower-body strength and power across different phases of the season. This highlights the importance for training programs to differ between junior and senior athletes and target different physical qualities for both groups at different times of the season, thus providing guidance for strength and conditioning coaches., (Copyright © 2020 National Strength and Conditioning Association.)

Abstract: Johnston, RD, Thornton, HR, Wade, JA, Devlin, P, and Duthie, GM. The distribution of match activities relative to the maximal mean intensities in professional rugby league and Australian football. J Strength Cond Res 36(5): 1360-1366, 2022-This study determined the distribution of distance, impulse, and accelerometer load accumulated at intensities relative to the maximal mean 1-minute peak intensity within professional rugby league and Australian football. Within 26 rugby league (n = 24 athletes) and 18 Australian football (n = 38 athletes) games, athletes wore global navigation satellite system devices (n = 608 match files). One-minute maximal mean values were calculated for each athlete per game for speed (m·minP-1P), accelerometer load (AU·minP-1P), and acceleration (m·sP-2P). Volumes for each parameter were calculated by multiplying by time, specifying total distance, accelerometer load, and impulse. The distribution of intensity of which these variables were performed relative to the maximal mean was calculated, with percentages ranging from 0-110%, separated into 10% thresholds. Linear mixed models determined whether the distribution of activities within each threshold varied, and positional differences. Effects were described using standardized effect sizes (ESs), and magnitude-based decisions. Across both sports, the distribution of activity (%) largely reduced the closer to the maximal mean 1-minute peak and was highest at ∼60% of the maximal mean peak. When compared with Australian football, a higher percentage of total distance was accumulated at higher intensities (70-80% and 100-110%) for rugby league (ES range = 0.82-0.87), with similar, yet larger differences for accelerometer load >80% (0.78-1.07) and impulse >60% (1.00-2.26). These findings provide information of the volume of activities performed relative to the mean maximal 1-minute peak period, which may assist in the prescription of training., (Copyright © 2020 National Strength and Conditioning Association.)