Deteriorations in physical qualities during a 10-week unsupervised off-season period in academy rugby union players. Issue 3 (3rd July 2022)

• Record Type: Journal Article
• Authors: Twist, Craig; Williams, Jack; Dobbin, Nick
• Is Part Of: Science and medicine in football. Volume 6:Issue 3(2022)
• Page Start: 347
• Page End: 354
• Publication Date: 2022-07-03
• Subjects: Intermittent sport -- detraining -- periodisation; Soccer injuries -- Periodicals; Soccer -- Physiological aspects -- Periodicals; Sports medicine -- Periodicals; Soccer -- Psychological aspects -- Periodicals; 617.102763
• DOI: 10.1080/24733938.2021.1959944
• Languages: English
• ISSNs: 2473-3938

Abstract

ABSTRACT: Purpose: To determine the changes in physical qualities of academy rugby union players over a 10-week unsupervised off-season period. Methods: Body mass, jump height, sprint performance, and intermittent running (30:15 IFT) of 64 academy rugby union players (age = 17.2 ± 0.4 y) were recorded before and after the off-season. Results: Changes in body mass (+1.4 ± 1.3 kg), countermovement jump (−2.2 ± 1.2 cm), squat jump (-1.5 ± 1.8 cm), 10 m sprint (+0.06 ± 0.05 s), 40 m sprint (+0.13 ± 0.11 s) and 30:15 IFT (-0.8 ± 0.8 kmŸh −1 ) were observed ( P < 0.001, d = -1.77 to 0.47). Only changes in body mass were greater in forwards than backs (P = 0.036, d = 0.46). Players with higher end-of-season body mass, squat jump and 30:15 IFT had greater off-season changes ( P = < 0.001 to 0.044; d = 0.63 to 0.94), whilst the pre-post difference in body mass influenced CMJ ( P = 0.005, d = 0.75) and 10 m momentum change ( P < 0.001, d = 1.61). Conclusion: Understanding the individuality of the changes in physical qualities of academy rugby union players during the off-season is important to ensure players return safely to pre-season training loads.