PURPOSE: To evaluate the difference in performance of the 30-15 Intermittent Fitness Test (30-15IFT) across 4 squads in a professional rugby union club in the UK and consider body mass in the interpretation of the end velocity of the 30-15IFT (VIFT). METHODS: One hundred fourteen rugby union players completed the 30-15IFT midseason. RESULTS: VIFT demonstrated small and possibly lower (ES = -0.33; 4/29/67) values in the under 16s compared with the under 21s, with further comparisons unclear. With body mass included as a covariate, all differences were moderate to large and very likely to almost certainly lower in the squads with lower body mass, with the exception of comparisons between senior and under-21 squads. CONCLUSIONS: The data demonstrate that there appears to be a ceiling to the VIFT attained in rugby union players that does not increase from under-16 to senior level. However, the associated increases in body mass with increased playing level suggest that the ability to perform high-intensity running increases with age, although not translating into greater VIFT due to the detrimental effect of body mass on change of direction. Practitioners should be aware that VIFT is unlikely to improve, but it needs to be monitored during periods where increases in body mass are evident.
PURPOSE: To evaluate the difference in performance of the 30-15 Intermittent Fitness Test (30-15IFT) across 4 squads in a professional rugby union club in the UK and consider body mass in the interpretation of the end velocity of the 30-15IFT (VIFT). METHODS: One hundred fourteen rugby union players completed the 30-15IFT midseason. RESULTS: VIFT demonstrated small and possibly lower (ES = -0.33; 4/29/67) values in the under 16s compared with the under 21s, with further comparisons unclear. With body mass included as a covariate, all differences were moderate to large and very likely to almost certainly lower in the squads with lower body mass, with the exception of comparisons between senior and under-21 squads. CONCLUSIONS: The data demonstrate that there appears to be a ceiling to the VIFT attained in rugby union players that does not increase from under-16 to senior level. However, the associated increases in body mass with increased playing level suggest that the ability to perform high-intensity running increases with age, although not translating into greater VIFT due to the detrimental effect of body mass on change of direction. Practitioners should be aware that VIFT is unlikely to improve, but it needs to be monitored during periods where increases in body mass are evident.
Authors: Dale Read; Daniel Weaving; Padraic Phibbs; Joshua Darrall-Jones; Gregory Roe; Jonathon Weakley; Sharief Hendricks; Kevin Till; Ben Jones Journal: BMJ Open Sport Exerc Med Date: 2017-03-10
Authors: Michael J Hamlin; Richard W Deuchrass; Catherine E Elliot; Nuttaset Manimmanakorn Journal: J Exerc Sci Fit Date: 2021-01-31 Impact factor: 3.103
Authors: Keith A Stokes; Ben Jones; Mark Bennett; Graeme L Close; Nicholas Gill; James H Hull; Andreas M Kasper; Simon P T Kemp; Stephen D Mellalieu; Nicholas Peirce; Bob Stewart; Benjamin T Wall; Stephen W West; Matthew Cross Journal: Int J Sports Med Date: 2020-05-29 Impact factor: 3.118