The Reliability of a Rugby League Movement-Simulation Protocol Designed to Replicate the Performance of Interchanged Players

2013 ◽  
Vol 8 (5) ◽  
pp. 483-489 ◽  
Author(s):  
Mark Waldron ◽  
Jamie Highton ◽  
Craig Twist

Purpose:This study assessed the reliability of a rugby league movement-simulation protocol, relative to interchanged players (RLMSP-i).Methods:Fifteen male participants completed 2 trials of the RLMSP-i, separated by 1 wk. The RLMSP-i comprised low- to moderate-intensity running, interspersed by high-intensity sprinting and tackling activity, based on global positioning system (GPS) data recorded during Super League performances.Results:The lowest coefficient of variation (CV ± 95% CI) was observed for total m/min during both interchange bout 1 (1.1% ± 0.2%) and bout 2 (1.0% ± 0.2%). The percentage of heart rate peak and ratings of perceived exertion demonstrated CVs of 1.2–2.0% and 2.9–3.5%, respectively. The poorest agreement between trials was found for blood lactate concentration (16.2% ± 2.8%). In no case was the CV smaller than the smallest worthwhile change, yet in every case the moderate changes were larger than the CV.Conclusions:The RLMSP-i’s reliability is sufficient to enable the detection of moderate changes in various performance and physiological measurements that accurately simulate some, but not all, aspects of rugby league matches.

2015 ◽  
Vol 10 (6) ◽  
pp. 746-753 ◽  
Author(s):  
Thomas Mullen ◽  
Jamie Highton ◽  
Craig Twist

It is important to understand the extent to which physical contact changes the internal and external load during rugby simulations that aim to replicate the demands of match play. Accordingly, this study examined the role of physical contact on the physiological and perceptual demands during and immediately after a simulated rugby league match. Nineteen male rugby players completed a contact (CON) and a noncontact (NCON) version of the rugby league match-simulation protocol in a randomized crossover design with 1 wk between trials. Relative distance covered (ES = 1.27; ±0.29), low-intensity activity (ES = 1.13; ±0.31), high-intensity running (ES = 0.49; ±0.34), heart rate (ES = 0.52; ±0.35), blood lactate concentration (ES = 0.78; ±0.34), rating of perceived exertion (RPE) (ES = 0.72; ±0.38), and session RPE (ES = 1.45; ±0.51) were all higher in the CON than in the NCON trial. However, peak speeds were lower in the CON trial (ES = −0.99; ±0.40) despite unclear reductions in knee-extensor (ES = 0.19; ±0.40) and -flexor (ES = 0.07; ±0.43) torque. Muscle soreness was also greater after CON than in the NCON trial (ES = 0.97; ±0.55). The addition of physical contact to the movement demands of a simulated rugby league match increases many of the external and internal demands but also results in players’ slowing their peak running speed during sprints. These findings highlight the importance of including contacts in simulation protocols and training practices designed to replicate the demands of real match play.


2021 ◽  
Vol 16 (1) ◽  
pp. 154-157
Author(s):  
Naoya Takei ◽  
Katsuyuki Kakinoki ◽  
Olivier Girard ◽  
Hideo Hatta

Background: Training in hypoxia versus normoxia often induces larger physiological adaptations, while this does not always translate into additional performance benefits. A possible explanation is a reduced oxygen flux, negatively affecting training intensity and/or volume (decreasing training stimulus). Repeated Wingates (RW) in normoxia is an efficient training strategy for improving both physiological parameters and exercise capacity. However, it remains unclear whether the addition of hypoxia has a detrimental effect on RW performance. Purpose: To test the hypothesis that acute moderate hypoxia exposure has no detrimental effect on RW, while both metabolic and perceptual responses would be slightly higher. Methods: On separate days, 7 male university sprinters performed 3 × 30-s Wingate efforts with 4.5-min passive recovery in either hypoxia (FiO2: 0.145) or normoxia (FiO2: 0.209). Arterial oxygen saturation was assessed before the first Wingate effort, while blood lactate concentration and ratings of perceived exertion were measured after each bout. Results: Mean (P = .92) and peak (P = .63) power outputs, total work (P = .98), and the percentage decrement score (P = .25) were similar between conditions. Arterial oxygen saturation was significantly lower in hypoxia versus normoxia (92.0% [2.8%] vs 98.1% [0.4%], P < .01), whereas blood lactate concentration (P = .78) and ratings of perceived exertion (P = .51) did not differ between conditions. Conclusion: In sprinters, acute exposure to moderate hypoxia had no detrimental effect on RW performance and associated metabolic and perceptual responses.


1996 ◽  
Vol 28 (4) ◽  
pp. 490-495 ◽  
Author(s):  
NANCY M. STOUDEMIRE ◽  
LAURIE WIDEMAN ◽  
KIMBERLY A. PASS ◽  
CHRISTINA L. McGINNES ◽  
GLENN A. GAESSER ◽  
...  

2007 ◽  
Vol 17 (2) ◽  
pp. 206-217 ◽  
Author(s):  
Guilherme Giannini Artioli ◽  
Bruno Gualano ◽  
Desiré Ferreira Coelho ◽  
Fabiana Braga Benatti ◽  
Alessandra Whyte Gailey ◽  
...  

The aim of the present study was to investigate whether pre exercise sodium-bicarbonate ingestion improves judo-related performance. The study used 2 different protocols to evaluate performance: 3 bouts of a specific judo test (n = 9) and 4 bouts of the Wingate test for upper limbs (n = 14). In both protocols athletes ingested 0.3 g/kg of sodium bicarbonate or placebo 2 h before the tests. Blood samples were collected to determine lactate level, and levels of perceived exertion were measured throughout the trials. The study used a double-blind, counterbalanced, crossover design. Ingestion of sodium bicarbonate improved performance in Bouts 2 and 3 of Protocol 1 (P < 0.05), mean power in Bouts 3 and 4 of Protocol 2 (P < 0.05), and peak power in Bout 4 of Protocol 2 (P < 0.05). Ingestion of bicarbonate increased lactate concentration in Protocol 1 (P < 0.05) but not in Protocol 2. Ratings of perceived exertion did not differ between treatments. In conclusion, sodium bicarbonate improves judo-related performance and increases blood lactate concentration but has no effect on perceived exertion.


Author(s):  
Garrison Draper ◽  
Matthew Wright ◽  
Paul Chesterton ◽  
Greg Atkinson

The aim was to assess factor structure of player-reported fatigue and quantify within-subjects association between changes in training load measures and next day player-reported fatigue at different time points of an elite football season. Using longitudinal research design, twenty-four professional footballers, mean (SD) age of 25.7 (3.4) years, were monitored during their competitive season, including pre-season. Player-reported fatigue data and session ratings of perceived exertion (session-RPE) were collected via a mobile application. Player’s Heart rate (HR) and global positioning system (GPS) data were collected daily for each player in field sessions. Principal component analysis (PCA) indicated three components with Eigenvalues above 1.0; “soreness”, “mood, and “hydration”. Within-player correlations between training load values and next day player-reported fatigue values were trivial to moderate (r ≈ −0.42 to −0.04). In-season we observed large correlations between Total Distance (TD) and PlayerLoad with Soreness (r = −0.55, 95% CI: −0.62 to −0.46; r = −.054, 95% CI: −0.62 to −0.46), but during pre-season, correlations were small (r = −0.15, 95% CI: −0.28 to −0.01; r = −0.13, 95% CI: −0.26 to 0.01). The HR TRIMP, TD and session-RPE measures each showed trivial to moderate correlations (r ≈ −0.41 to −0.08) with next day “mood”. Our in-house player-reported fatigue questionnaire was sensitive to the multi-dimensional nature of fatigue, identifying physiological (soreness), psychological (mood and stress) and nutritional (hydration and nutrition) components. We found the in-season correlations with training load to be greater than previously reported in the literature, specifically with next day player-reported “soreness”. Nevertheless, the correlations between the items of our scale and pre-season training load were small.


2016 ◽  
Vol 11 (3) ◽  
pp. 404-406 ◽  
Author(s):  
Shaun J. McLaren ◽  
Michael Graham ◽  
Iain R. Spears ◽  
Matthew Weston

Purpose:To investigate the sensitivity of differential ratings of perceived exertion (dRPE) as measures of internal load.Methods:Twenty-two male university soccer players performed 2 maximal incremental-exercise protocols (cycle, treadmill) on separate days. Maximal oxygen uptake (V̇O2max), maximal heart rate (HRmax), peak blood lactate concentration (B[La]peak), and the preprotocol-to-postprotocol change in countermovement-jump height (ΔCMJH) were measured for each protocol. Players provided dRPE (CR100) for breathlessness (RPE-B) and leg-muscle exertion (RPE-L) immediately on exercise termination (RPE-B0, RPE-L0) and 30 min postexercise (RPE-B30, RPE-L30). Data were analyzed using magnitude-based inferences.Results:There were clear between-protocols differences for V̇O2max (cycle 46.5 ± 6.3 vs treadmill 51.0 ± 5.1 mL · kg−1 · min−1, mean difference –9.2%; ±90% confidence limits 3.7%), HRmax (184.7 ± 12.7 vs 196.7 ± 7.8 beats/min, –6.0%; ±1.7%), B[La]peak (9.7 ± 2.1 vs 8.5 ± 2.0 mmol/L, 15%; ±10%), and ΔCMJH (–7.1 ± 4.2 vs 0.6 ± 3.6 cm, –23.2%; ±5.4%). Clear between-protocols differences were recorded for RPE-B0 (78.0 ± 11.7 vs 94.7 ± 9.5 AU, –18.1%; ±4.5%), RPE-L0 (92.6 ± 9.7 vs 81.3 ± 14.1 AU, 15.3%; ±7.6%), RPE-B30 (70 ± 11 vs 82 ± 13 AU, –13.8%; ±7.3%), and RPE-L30 (86 ± 12 vs 65 ± 19 AU, 37%; ±17%). A substantial timing effect was observed for dRPE, with moderate to large reductions in all scores 30 min postexercise compared with scores collected on exercise termination.Conclusion:dRPE enhance the precision of internal-load measurement and therefore represent a worthwhile addition to training-load-monitoring procedures.


2014 ◽  
Vol 9 (1) ◽  
pp. 58-67 ◽  
Author(s):  
Dennis-Peter Born ◽  
Christoph Zinner ◽  
Britta Herlitz ◽  
Katharina Richter ◽  
Hans-Christer Holmberg ◽  
...  

Purpose:The current investigation assessed tissue oxygenation and local blood volume in both vastus lateralis muscles during 3000-m race simulations in elite speed skaters on ice and the effects of leg compression on physiological, perceptual, and performance measures.Methods:Ten (6 female) elite ice speed skaters completed 2 on-ice trials with and without leg compression. Tissue oxygenation and local blood volume in both vastus lateralis muscles were assessed with near-infrared spectroscopy. Continuous measures of oxygen uptake, ventilation, heart rate, and velocity were conducted throughout the race simulations, as well as blood lactate concentration and ratings of perceived exertion before and after the trials. In addition, lap times were assessed.Results:The investigation of tissue oxygenation in both vastus lateralis muscles revealed an asymmetry (P < .00; effect size = 1.81) throughout the 3000-m race simulation. The application of leg compression did not affect oxygenation asymmetry (smallest P = .99; largest effect size = 0.31) or local blood volume (P = .33; 0.95). Lap times (P = .88; 0.43), velocity (P = .24; 0.84), oxygen uptake (P = .79; 0.10), ventilation (P = .11; 0.59), heart rate (P = .21; 0.89), blood lactate concentration (P = .82; 0.59), and ratings of perceived exertion (P = .19; 1.01) were also unaffected by the different types of clothing.Conclusion:Elite ice speed skaters show an asymmetry in tissue oxygenation of both vastus lateralis muscles during 3000-m events remaining during the long gliding phases along the straight sections of the track. Based on the data, the authors conclude that there are no performance-enhancing benefits from wearing leg compression under a normal racing suit.


2019 ◽  
Vol 14 (4) ◽  
pp. 445-450 ◽  
Author(s):  
Jonathan P. Norris ◽  
Jamie Highton ◽  
Craig Twist

Purpose: To assess the reliability and external validity of a rugby league movement-simulation protocol for interchange players (RLMSP-i) that was adapted to include physical contact between participants. Methods: A total of 18 rugby players performed 2 trials of a modified RLMSP-i, 7 d apart. The simulation was conducted outdoors on artificial turf with movement speeds controlled using an audio signal. Microtechnology was used to measure locomotive and accelerometer (ie, PlayerLoad™) metrics for both bouts (∼23 min each) alongside heart rate (HR) and rating of perceived exertion (RPE). Results: Reported for each bout, total distance (102 [3] m·min−1 and 101 [3] m·min−1), low-speed distance (77 [3] m·min−1 and 79 [4] m·min−1), high-speed distance (25 [3] m·min−1 and 22 [4] m·min−1), PlayerLoad (10 [1] AU·min−1 and 10 [1] AU·min−1), PlayerLoad slow (3.2 [0.6] AU·min−1 and 3.2 [0.6] AU·min−1), 2-dimensional PlayerLoad (6.0 [0.9] AU·min−1 and 5.7 [0.8] AU·min−1), and HR (86 [5]%HRmax and 84 [6]%HRmax) were similar to match play. The coefficient of variation (CV%) for locomotive metrics ranged from 1.3% to 14.4%, accelerometer CV% 4.4% to 10.0%, and internal load 4.8% to 13.7%. All variables presented a CV% less than the calculated moderate change during 1 or both bouts of the simulation except high-speed distance, percentage of the participant’s peak HR, and RPE. Conclusion: The modified RLMSP-i offers a reliable simulation to investigate influences of training and nutrition interventions on the movement and collision activities of rugby league interchange players.


Sign in / Sign up

Export Citation Format

Share Document