TY - JOUR
T1 - The validity and contributing physiological factors to 30-15 intermittent fitness test performance in rugby league
AU - Scott, Tannath J.
AU - Duthie, Grant M.
AU - Delaney, Jace A.
AU - Sanctuary, Colin E.
AU - Ballard, David A.
AU - Hickmans, Jeremy A.
AU - Dascombe, Ben J.
PY - 2017
Y1 - 2017
N2 - This study examined the validity of the 30-15 Intermittent Fitness Test (30-15 IFT) within rugby league. Sixty-three Australian elite and junior-elite rugby league players (22.5 ± 4.5 years, 96.1 ± 9.5 kg, Σ7 skinfolds: 71.0 ± 18.7 mm) from a professional club participated in this study. Players were assessed for anthropometry (body mass, Σ7 skinfolds, lean mass index), prolonged high-intensity intermittent running (PHIR; measured by 30-15 IFT), predicted aerobic capacity (MSFT) and power (AAS), speed (40 m sprint), repeated sprint, and change of direction (COD - 505 agility test) ability before and after an 11-week preseason training period. Validity of the 30-15 IFT was established using Pearson's coefficient correlations. Forward stepwise regression model identified the fewest variables that could predict individual final velocity (V IFT) and change within 30-15 IFT performance. Significant correlations between V IFT and Σ7 skinfolds, repeated sprint decrement, Vo 2 max MSFT, and average aerobic speed were observed. A total of 71.8% of the adjusted variance in 30-15 IFT performance was explained using a 4-step best fit model (Vo 2 max MSFT, 61.4%; average aerobic speed, 4.7%; maximal velocity, 4.1%; lean mass index, 1.6%). Across the training period, 25% of the variance was accounted by ΔVo 2 max MSFT (R 2 = 0.25). These relationships suggest that the 30-15 IFT is a valid test of PHIR within rugby league. Poor correlations were observed with measures of acceleration, speed, and COD. These findings demonstrate that although the 30-15 IFT is a valid measure of PHIR, it also simultaneously examines various physiological capacities that differ between sporting cohorts.
AB - This study examined the validity of the 30-15 Intermittent Fitness Test (30-15 IFT) within rugby league. Sixty-three Australian elite and junior-elite rugby league players (22.5 ± 4.5 years, 96.1 ± 9.5 kg, Σ7 skinfolds: 71.0 ± 18.7 mm) from a professional club participated in this study. Players were assessed for anthropometry (body mass, Σ7 skinfolds, lean mass index), prolonged high-intensity intermittent running (PHIR; measured by 30-15 IFT), predicted aerobic capacity (MSFT) and power (AAS), speed (40 m sprint), repeated sprint, and change of direction (COD - 505 agility test) ability before and after an 11-week preseason training period. Validity of the 30-15 IFT was established using Pearson's coefficient correlations. Forward stepwise regression model identified the fewest variables that could predict individual final velocity (V IFT) and change within 30-15 IFT performance. Significant correlations between V IFT and Σ7 skinfolds, repeated sprint decrement, Vo 2 max MSFT, and average aerobic speed were observed. A total of 71.8% of the adjusted variance in 30-15 IFT performance was explained using a 4-step best fit model (Vo 2 max MSFT, 61.4%; average aerobic speed, 4.7%; maximal velocity, 4.1%; lean mass index, 1.6%). Across the training period, 25% of the variance was accounted by ΔVo 2 max MSFT (R 2 = 0.25). These relationships suggest that the 30-15 IFT is a valid test of PHIR within rugby league. Poor correlations were observed with measures of acceleration, speed, and COD. These findings demonstrate that although the 30-15 IFT is a valid measure of PHIR, it also simultaneously examines various physiological capacities that differ between sporting cohorts.
UR - https://hdl.handle.net/1959.7/uws:71560
U2 - 10.1519/JSC.0000000000001702
DO - 10.1519/JSC.0000000000001702
M3 - Article
SN - 1064-8011
VL - 31
SP - 2409
EP - 2416
JO - Journal of Strength and Conditioning Research
JF - Journal of Strength and Conditioning Research
IS - 9
ER -