Acceleration-Based Running Intensities of Professional Rugby League Match Play.

Rugby league involves frequent periods of high-intensity running including acceleration and deceleration efforts, often occurring at low speeds.
Purpose: To quantify the energetic cost of running and acceleration efforts during rugby league competition to aid in prescription and monitoring of training.
Methods: Global positioning system (GPS) data were collected from 37 professional rugby league players across 2 seasons. Peak values for relative distance, average acceleration/deceleration, and metabolic power (P _met ) were calculated for 10 different moving-average durations (1-10 min) for each position. A mixed-effects model was used to assess the effect of position for each duration, and individual comparisons were made using a magnitude-based-inference network.
Results: There were almost certainly large differences in relative distance and P _met between the 10-min window and all moving averages <5 min in duration (ES = 1.21-1.88). Fullbacks, halves, and hookers covered greater relative distances than outside backs, edge forwards, and middle forwards for moving averages lasting 2-10 min. Acceleration/deceleration demands were greatest in hookers and halves compared with fullbacks, middle forwards, and outside backs. P _met was greatest in hookers, halves, and fullbacks compared with middle forwards and outside backs.
Conclusions: Competition running intensities varied by both position and moving-average duration. Hookers exhibited the greatest P _met of all positions, due to high involvement in both attack and defense. Fullbacks also reached high P _met , possibly due to a greater absolute volume of running. This study provides coaches with match data that can be used for the prescription and monitoring of specific training drills.