An Analysis of the Game Movement Demands of Women's Interprovincial Rugby Union.

ABSTRACT: Callanan, D, Rankin, P, and Fitzpatrick, P. Analysis of the game movement demands of women's interprovincial rugby union. J Strength Cond Res 35(12S): S20-S25, 2021-The purpose of this study was to provide an objective analysis of the game movement demands of women's interprovincial rugby union (RU). Sixty-three (N = 128) interprovincial women RU players wore 10-Hz global positioning systems (PlayerTek by Catapult, Australia) during 12 interprovincial matches (116 individual player data sets). Players were classified according to forwards and backs, and positional subcategory groups: front row second row, back row, half-back, midfield, and back three. The mean total distance covered across the series was 5,696 ± 822 m, at a relative distance of 67.9 ± 6.9 m·min-1, while recording a mean maximal velocity of 6.5 ± 0.7 m·s-1. The backs covered a greater total distance (5,964 ± 807 m; d = 0.65), relative distance (70.1 ± 7.5 m·min-1; d = 0.63), mean maximal velocity (6.9 ± 0.5 m·s-1; d = 1.27), distance walking (1,152 ± 152 m; d = 0.54), jogging (3,120 ± 519 m; d = 0.56), and high-speed running (294 ± 150 m; d = 0.99) than the forwards. The midfield recorded the greatest total distance (6,144 ± 516 m; p = 0.013), with the front row registering the lowest. The half backs documented the greatest relative distance (73.2 ± 8.0 m·min-1; p = 0.005), with the back three reported to cover the greatest distances walking (1,169 ± 178 m; p = 0.001) and at high-speed distances (353 ± 175 m; p = 0.002). The back three also recorded the greatest mean maximal velocity (7.2 ± 0.4 m·s-1; p = 0.000). This is the first study in the Northern hemisphere to report the game movement demands of interprovincial women's RU and the information derived from this study may provide practitioners with normative data to assist coaches with preparation.

Potentiating Response to Drop-Jump Protocols on Sprint Acceleration: Drop-Jump Volume and Intrarepetition Recovery Duration.

Byrne, PJ, Moody, JA, Cooper, SM, Callanan, D, and Kinsella, S. Potentiating response to drop-jump protocols on sprint acceleration: drop-jump volume and intrarepetition recovery duration. J Strength Cond Res 34(3): 717-727, 2020-The purpose of this study was to investigate the postactivation potentiation response first to bounce drop jump (BDJ) volume; second, BDJ intrarepetition recovery duration and recovery duration between BDJs and 20-meter (including 5- and 10-m split times) sprint performance. The study was undertaken in 2 parts, the first part compared different volumes of BDJs and the second part compared different BDJ intrarepetition recovery periods. The effect of recovery periods between the BDJs and the subsequent 20-m sprints was examined in both parts 1 and 2 (15 seconds, 4, 8, and 12 minutes). Fourteen (mean ± SD: age = 20.83 ± 1.26 years; height = 1.77 ± 0.04 m; and mass = 74.89 ± 6.07 kg) (part 1) and 15 (mean ± SD: age = 20.64 ± 1.00 years; height = 1.78 ± 0.06 m; and mass = 75.67 ± 6.28 kg) (part 2) male collegiate and club hurling players volunteered to participate. A randomized cross-over design was used to compare BDJ volumes (1, 2, and 3 sets of 3 repetitions) and BDJ intrarepetition recovery time (15 vs. 60 seconds) after a warm-up followed by 2 baseline 20-m sprints. The results in part 1 reported a significant improvement in 5- and 10-m sprint time for 1 set of 3 BDJs between baseline and 4 minutes (5 m: -2.34%, p = 0.04, effect size [ES] = -0.043; 10 m: -1.42%, p = 0.03, ES = -0.35), and baseline and 12 minutes (5 m: -3.33%, p = 0.03, ES = -0.57; 10 m: -2.13%, p = 0.01, ES = -0.52). Part 2 reported a significant improvement in 5-m sprint time between baseline and 15 seconds (5 m: -3.38%, p = 0.01, ES = -0.83; 10 m: -2.07%, p = 0.02, ES = -0.58) after the BDJs. The findings support the use of 1 set of 3 BDJs using a 15-second intrarepetition recovery period to maximize 5-, 10-, and 20-m sprint performance after 15 seconds of recovery after the final BDJ in hurling players. The acute response to this BDJ protocol proves to be time efficient and effective in acutely improving sprint acceleration.

Can Milk Affect Recovery from Simulated Team-Sport Match Play?

This study investigated the effects of cow's milk on recovery from repeated simulated team games (STGs) in females. Twenty female team-sport athletes completed an STG circuit (2x ~ 30 min, with 10 min 'half-time'). Measures of muscle function, soreness and tiredness, symptoms of stress and serum markers of muscle damage and oxidative stress were determined pre- and 24 h, 48 h, 72 h and 96 h following the circuit. At 48 h, a second STG was completed. Sprint performance (5 m, 15 m), lap time, countermovement jump (CMJ), heart rate and RPE were recorded during each STG. Immediately following each STG, participants consumed either 500 mL of cow's milk (MILK) or 500 mL of an energy-matched carbohydrate (CHO) solution. Compared to CHO, MILK had a beneficial effect in attenuating losses in peak torque for knee extension (60°/s) (likely; effect size (ES) = 0.26 to 0.28) knee flexion (60°/s) (likely; ES = 0.45 to 0.61). A benefit for MILK was observed for 5 m sprint (possible-likely; ES = 0.40 to 0.58), 10 m sprint (likely; ES = 0.30 to 0.53) and symptoms of stress (likely-very likely, small). Mostly unclear outcomes for other variables were observed. For STG variables, trivial (HR, CMJ) and unclear (5 m sprint, 15 m sprint, lap-time, RPE) outcomes were recorded. In conclusion, the consumption of 500 mL of milk attenuated losses in muscle function and perceptions of stress following repeated simulated team-sports games. However, further investigation is warranted to determine whether MILK can influence subsequent team-sport performance.