Search Results

You are looking at 1 - 10 of 33 items for :

  • "30-15 Intermittent Fitness Test" x
Clear All
Restricted access

Christopher Thomas, Thomas Dos’Santos, Paul A. Jones and Paul Comfort

Purpose:

The purpose of this investigation was to determine the reliability of the 30-15 Intermittent Fitness Test (30-15IFT) in semiprofessional soccer players.

Methods:

Fourteen male semiprofessional soccer players performed the 30-15IFT on 2 occasions separated by 7 d. Reliability was assessed by intraclass correlation coefficient (ICC), typical error of measurement expressed as a coefficient of variation (CV), and smallest worthwhile change (SWC) to determine any significant difference between testing sessions.

Results:

Maximal intermittent running velocity (VIFT) demonstrated good reliability (ICC = .80) for between-sessions reliability. The CV was 2.5% for between-sessions reliability of the 30-15IFT. As the SWC (0.70 km/h) falls within the range in which the individual’s true score is likely to lie (1.0 km/h), the usefulness of the VIFT was rated as marginal. Despite the usefulness of the 30-15IFT being deemed marginal, a change in performance as small as 1.0 km/h (2 stages) in VIFT could be considered substantial or real.

Conclusion:

This study demonstrates that VIFT in the 30-15IFT is reliable, resulting in a reliable assessment of team-sport-specific cardiorespiratory fitness, with changes as small as 1.0 km/h (2 stages) in VIFT considered meaningful.

Restricted access

Joshua Darrall-Jones, Gregory Roe, Shane Carney, Ryan Clayton, Padraic Phibbs, Dale Read, Jonathon Weakley, Kevin Till and Ben Jones

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.

Restricted access

Martin Buchheit and Alireza Rabbani

The aim of the current study was to examine the relationship between performance of the Yo-Yo Intermittent Recovery Test Level 1 (Yo-YoIR1) and the 30–15 Intermittent Fitness Test (30-15IFT) and to compare the sensitivity of both tests to training. Fourteen young soccer players performed both tests before and after an 8-wk training intervention, which included 6 sessions/wk: 2 resistance training sessions, 2 high-intensity interval training sessions after technical training (4 sets of 3:30 min of generic running and small-sided games [4v4] during the first and second 4-wk periods, respectively [90–95% maximal HR], interspersed with 3 min at 60–70% maximal HR), and 2 tactical-only training sessions. There was a large correlation between 30-15IFT and Yo-YoIR1 (r = .75, 90% confidence limits [CL] 0.57;0.86). While within-test percentage changes suggested a greater sensitivity to training for the Yo-YoIR1 (+35%, 90%CL 24;45) than for the 30-15IFT (+7%; 4;10), these changes were similarly rated as almost certain (with chances for greater/similar/lower values after training of 100/0/0 for both tests) and moderate, ie, standardized difference, ES = +1.2 90%CL (0.9;1.5) for Yo-YoIR1 and ES = +1.1 (0.7;1.5) for 30-15IFT. The difference in the change between the 2 tests was clearly trivial (0/100/0, ES = –0.1, 90%CL –0.1;–0.1). Both tests might evaluate slightly different physical capacities, but their sensitivity to training is almost certainly similar. These results also highlight the importance of using standardized differences instead of percentage changes in performance to assess the actual training effect of an intervention.

Restricted access

Tannath J. Scott, Heidi R. Thornton, Macfarlane T.U. Scott, Ben J. Dascombe and Grant M. Duthie

at VT 2IFT  = 87% V IFT , and GRCF = grass-running correction factor = 1.29. 10 30-15 Intermittent Fitness Test To measure individual’s mixed aerobic/anaerobic fitness levels 7 and consequently update relative thresholds throughout the season, participants were required to complete the 30-15 IFT at

Restricted access

Mitchell J. Henderson, Job Fransen, Jed J. McGrath, Simon K. Harries, Nick Poulos and Aaron J. Coutts

Aerobic capacity can be assessed using endurance performance tests (eg, 2-km time trial) and intermittent tests (eg, 30:15 intermittent fitness test [30:15 IFT ]). 6 However, these 2 types of aerobic tests measure distinctly different physical characteristics; the 30:15 IFT assesses both aerobic and

Restricted access

Alireza Rabbani, Mehdi Kargarfard, Carlo Castagna, Filipe Manuel Clemente and Craig Twist

-season phase. Figure 1 —NBL and Edwards TRIMP distribution during selected in-season phase. 30-15 IFT indicates 30-15 Intermittent Fitness Test; AU, arbitrary units; NBL, new body load; TRIMP, training impulse. Error bars represent the SD. Methodology 30-15 Intermittent Fitness Test After habituation, each

Restricted access

Dawn Scott, Dean Norris and Ric Lovell

gates (Smart Speed Pro System, Brisbane, QLD, Australia) were positioned at 10 minutes intervals, with PS determined as the fastest split time, as per previous soccer studies. 12 , 18 Following a 60 minutes rest period, the players completed the 30:15 intermittent fitness test (IFT). Players had

Restricted access

Calvin P. Philp, Martin Buchheit, Cecilia M. Kitic, Christopher T. Minson and James W. Fell

Purpose:

To investigate whether a 5-d cycling training block in the heat (35°C) in Australian Rules footballers was superior to exercising at the same relative intensity in cool conditions (15°C) for improving intermittent-running performance in a cool environment (<18°C).

Methods:

Using a parallel-group design, 12 semiprofessional football players performed 5 d of cycling exercise (70% heart-rate reserve [HRR] for 45 min [5 × 50-min sessions in total]) in a hot (HEAT, 35°C ± 1°C, 56% ± 9% RH) or cool environment (COOL, 15°C ± 3°C, 81% ± 10% RH). A 30-15 Intermittent Fitness Test to assess intermittent running performance (VIFT) was conducted in a cool environment (17°C ± 2°C, 58 ± 5% RH) before and twice after (1 and 3 d) the intervention.

Results:

There was a likely small increase in VIFT in each group (HEAT, 0.5 ± 0.3 km/h, 1.5 ± 0.8 × smallest worthwhile change [SWC]; COOL, 0.4 ± 0.4 km/h, 1.6 ± 1.2 × SWC) 3 d postintervention, with no difference in change between the groups (0.5% ± 1.9%, 0.4 ± 1.4 × SWC). Cycle power output during the intervention was almost certainly lower in the HEAT group (HEAT 1.8 ± 0.2 W/kg vs COOL 2.5 ± 0.3 W/kg, –21.7 ± 3.2 × SWC, 100/0/0).

Conclusions:

When cardiovascularexercise intensity is matched (ie, 70% HRR) between environmental conditions, there is no additional performance benefit from short-duration moderate-intensity heat exposure (5 × 50 min) for semiprofessional footballers exercising in cool conditions. However, the similar positive adaptations may occur in HEAT with 30% lower mechanical load, which may be of interest for load management during intense training or rehabilitation phases.

Restricted access

Al Haddad Hani, Paul B. Laursen, Ahmaidi Said and Buchheit Martin

Purpose:

To assess the effect of supramaximal intermittent exercise on long-term cardiac autonomic activity, inferred from heart rate variability (HRV).

Methods:

Eleven healthy males performed a series of two consecutive intermittent 15-s runs at 95% VIFT (i.e., speed reached at the end of the 30-15 Intermittent Fitness Test) interspersed with 15 s of active recovery at 45% VIFT until exhaustion. Beat-to-beat intervals were recorded during two consecutive nights (habituation night and 1st night) before, 10 min before and immediately after exercise, as well as 12 h (2nd night) and 36 h (3rd night) after supramaximal intermittent exercise. The HRV indices were calculated from the last 5 min of resting and recovery periods, and the first 10 min of the first estimated slow wave sleep period.

Results:

Immediate post-supramaximal exercise vagal-related HRV indices were significantly lower than immediate pre-supramaximal exercise values (P < .001). Most vagal-related indices were lower during the 2nd night compared with the 1st night (eg, mean RR intervals, P = .03). Compared with the 2nd night, vagal-related HRV indices were significantly higher during the 3rd night. Variables were not different between the 1st and 3rd nights; however, we noted a tendency (adjusted effect size, aES) for an increased normalized high-frequency component (P = .06 and aES = 0.70) and a tendency toward a decreased low-frequency component (P = .06 and aES = 0.74).

Conclusion:

Results confirm the strong influence of exercise intensity on short- and long-term post exercise heart rate variability recovery and might help explain the high efficiency of supramaximal training for enhancing indices of cardiorespiratory fitness.

Restricted access

Rich D. Johnston, Tim J. Gabbett and David G. Jenkins

Purpose:

To determine the influence the number of contact efforts during a single bout has on running intensity during game-based activities and assess relationships between physical qualities and distances covered in each game.

Methods:

Eighteen semiprofessional rugby league players (age 23.6 ± 2.8 y) competed in 3 off-side small-sided games (2 × 10-min halves) with a contact bout performed every 2 min. The rules of each game were identical except for the number of contact efforts performed in each bout. Players performed 1, 2, or 3 × 5-s wrestles in the single-, double-, and triple-contact game, respectively. The movement demands (including distance covered and intensity of exercise) in each game were monitored using global positioning system units. Bench-press and back-squat 1-repetition maximum and the 30−15 Intermittent Fitness Test (30−15IFT) assessed muscle strength and high-intensity-running ability, respectively.

Results:

There was little change in distance covered during the single-contact game (ES = −0.16 to −0.61), whereas there were larger reductions in the double- (ES = −0.52 to −0.81) and triple-contact (ES = −0.50 to −1.15) games. Significant relationships (P < .05) were observed between 30–15IFT and high-speed running during the single- (r = .72) and double- (r = .75), but not triple-contact (r = .20) game.

Conclusions:

There is little change in running intensity when only single contacts are performed each bout; however, when multiple contacts are performed, greater reductions in running intensity result. In addition, high-intensity-running ability is only associated with running performance when contact demands are low.