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Corrado Lupo, Alexandru Nicolae Ungureanu, Riccardo Frati, Matteo Panichi, Simone Grillo and Paolo Riccardo Brustio

, among team sports, basketball is characterized by progressive rule changes, which contribute to make interpretation of the ITL difficult without a valid method. In fact, basketball is characterized by intermittent high-intensity actions, 5 especially after rule modifications (offense from 30 to 24 s

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Greg Henry, Brian Dawson, Brendan Lay and Warren Young

Purpose:

To study the validity of a video-based reactive agility test in Australian footballers.

Methods:

15 higher performance, 15 lower performance, and 12 nonfootballers completed a light-based reactive agility test (LRAT), a video-based reactive agility test (VRAT), and a planned test (PLAN).

Results:

With skill groups pooled, agility time in PLAN (1346 ± 66 ms) was significantly faster (P = .001) than both reactive tests (VRAT = 1550 ± 102 ms; LRAT = 1572 ± 97 ms). In addition, decision time was significantly faster (P = .001; d = 0.8) in LRAT (278 ± 36 ms) than VRAT (311 ± 47 ms). The correlation in agility time between the two reactive tests (r = .75) was higher than between the planned and reactive tests (r = .41–.68). Higher performance players had faster agility and movement times on VRAT (agility, 130 ± 24 ms, d = 1.27, P = .004; movement, 69 ± 73 ms, d = 0.88, P = .1) and LRAT (agility, 95 ± 86 ms, d = 0.99, P = .08; movement, 79 ± 74 ms; d = 0.9; P = .08) than the nonfootballers. In addition, higher (55 ± 39 ms, d = 0.87, P = .05) and lower (40 ± 57 ms, d = 0.74, P = .18) performance groups exhibited somewhat faster agility time than nonfootballers on PLAN. Furthermore, higher performance players were somewhat faster than lower performance for agility time on the VRAT (63 ± 85 ms, d = 0.82, P = .16) and decision time on the LRAT (20 ± 39 ms, d = 0.66, P = .21), but there was little difference in PLAN agility time between these groups (15 ± 150 ms, d = 0.24, P = .8).

Conclusions:

Differences in decision-making speed indicate that the sport-specific nature of the VRAT is not duplicated by a light-based stimulus. In addition, the VRAT is somewhat better able to discriminate different groups of Australian footballers than the LRAT. Collectively, this indicates that a video-based test is a more valid assessment tool for examining agility in Australian footballers.

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Emma K. Zadow, Cecilia M. Kitic, Sam S.X. Wu, Stuart T. Smith and James W. Fell

Purpose:

To assess the validity of power output settings of the Wahoo KICKR Power Trainer (KICKR) using a dynamic calibration rig (CALRIG) over a range of power outputs and cadences.

Methods:

Using the KICKR to set power outputs, powers of 100–999 W were assessed at cadences (controlled by the CALRIG) of 80, 90, 100, 110, and 120 rpm.

Results:

The KICKR displayed accurate measurements of power of 250–700 W at cadences of 80–120 rpm with a bias of –1.1% (95% limits of agreement [LoA] –3.6% to 1.4%). A larger mean bias in power was observed across the full range of power tested, 100–999 W (4.2%, 95% LoA –20.1% to 28.6%), due to larger biases of 100–200 and 750–999 W (4.5%, 95% LoA –2.3% to 11.3%, and 13.0%, 95% LoA –24.4% to 50.3%), respectively.

Conclusions:

Compared with a CALRIG, the KICKR has acceptable accuracy reporting a small mean bias and narrow LoA in the measurement of power output of 250–700 W at cadences of 80–120 rpm. Caution should be applied by coaches and sports scientists when using the KICKR at power outputs of <200 W and >750 W due to the greater variability in recorded power.

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Nicola Furlan, Mark Waldron, Mark Osborne and Adrian J. Gray

Purpose:

To assess the ecological validity of the Rugby Sevens Simulation Protocol (R7SP) and to evaluate its interday reliability.

Methods:

Ten male participants (20 ± 2 y, 74 ± 11 kg) completed 2 trials of the R7SP, separated by 7 d. The R7SP comprised typical running and collision activities, based on data recorded during international rugby sevens match play. Heart rate (HR) was monitored continuously during the R7SP, and the participants’ movements were recorded through a 20-Hz global positioning system unit. Blood lactate and rating of perceived exertion were collected before and immediately after the 1st and 2nd halves of the R7SP.

Results:

The average activity profile was 117 ± 5 m/min, of which 27 ± 2 m/min was covered at high speed, with a calculated energetic demand of 1037 ± 581 J/kg, of which ~40% was expended at a rate above 19 W/kg. Mean HR was 88% ± 4% of maximal HR. Participants spent ~45% ± 27% of time above 90% of maximal HR (t >90%HRmax). There were no significant differences between trials, except for lactate between the halves of the R7SP. The majority of the measured variables demonstrated a between-trials coefficient of variation (CV%) lower than 5%. Blood lactate measurements (14–20% CV) and t >90%HRmax (26% CV) were less reliable variables. In most cases, the calculated moderate worthwhile change was higher than the CV%.

Conclusions:

The R7SP replicates the activity profile and HR responses of rugby sevens match play. It is a reliable simulation protocol that can be used in a research environment to detect systematic worthwhile changes in selected performance variables.

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Andrew C. Sparkes

Evaluating the quality of qualitative inquiry has begun to intrigue researchers in sport psychology. Consequently, this has raised important questions regarding the criteria for judging this emerging form of inquiry. With the intent to stimulate methodological debate, this paper explores prevailing notions of validity in qualitative sport psychology by focusing on how various scholars have framed this term. The prevailing parallel perspective of validity is discussed, as are specific problems associated with this view. In contrast, recent attempts to reconceptualize validity in relation to particular forms of qualitative inquiry are considered. The socially constructed nature of validity and the multiplicity of meanings associated with this term are presented according to a diversification perspective. More radical calls to renounce validity and seek alternative criteria for judging qualitative inquiry are also discussed. In closing, the ongoing problem of criteria and its implications for research in sport psychology are considered.

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Stephen J. Kelly, Aron J. Murphy, Mark L. Watsford, Damien Austin and Michael Rennie

Purpose:

To investigate the validity and reliability of accelerometry of the SPI-ProX II dual data logger (GPSports, Canberra, Australia).

Methods:

Controlled laboratory assessments determined the accuracy and reproducibility of raw accelerometer data. Intra- and interdevice reliability assessed the ability of the SPI-ProX II accelerometers to repeatedly measure peak gravitational accelerations (g) during impact-based testing. Static and dynamic validity testing assessed the accuracy of SPI-ProX II accelerometers against a criterion-referenced accelerometer. Dynamic validity was assessed over a range of frequencies from 5 to 15 Hz.

Results:

Intradevice reliability found no differences (P < .05) between 4 SPI-ProX II accelerometers, with a low coefficient of variation (1.87–2.21%). SPI-ProX II accelerometers demonstrated small to medium effect-size (ES) differences (0.10–0.44) between groups and excellent interdevice reliability, with no difference found between units (F = 0.826, P = .484). Validity testing revealed significant differences between devices (P = .001), with high percentage differences (27.5–30.5%) and a large ES (>3.44).

Conclusions:

SPI-ProX II accelerometers demonstrated excellent intra- and interaccelerometer reliability. However, static and dynamic validity were poor, and caution is recommended when measuring the absolute magnitude of acceleration, particularly for high-frequency movements. Regular assessment of individual devices is advised, particularly for mechanical damage and signal-drift errors. It is recommended that guidelines be provided by the manufacturer on measuring shifts in the base accelerometer signal, including time frames for assessing accelerometer axis, magnitude of errors, and calibration of accelerometers from a stable reference point.

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Clive J. Brewer and Robyn L. Jones

The purpose of this paper is to propose a five-stage process for establishing both validity and reliability in new systematic observation instruments. The process is contextualized within the working behaviors of elite level rugby union coaches within the practice setting. The sequential stages began with observer training and progressed through the identification of coaching behaviors through induction (to establish content validity), to establishing face validity through a domain-referenced test. The objectivity and reliability of the developed behavioral classifications are determined through an interobserver agreement test while, finally, the researcher’s ability to reliably reproduce data with the developed instrument is determined using a test/retest intraobserver reliability check. The developed instrument (the Rugby Union Coaches Observation Instrument: RUCOI) is deemed able to record the situationally unique behaviors arising from the nature of the sport and of the elite standard, both of which were considered to impinge upon the pedagogical process in the said context.

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Harry G. Banyard, Ken Nosaka, Kimitake Sato and G. Gregory Haff

Purpose:

To examine the validity of 2 kinematic systems for assessing mean velocity (MV), peak velocity (PV), mean force (MF), peak force (PF), mean power (MP), and peak power (PP) during the full-depth free-weight back squat performed with maximal concentric effort.

Methods:

Ten strength-trained men (26.1 ± 3.0 y, 1.81 ± 0.07 m, 82.0 ± 10.6 kg) performed three 1-repetition-maximum (1RM) trials on 3 separate days, encompassing lifts performed at 6 relative intensities including 20%, 40%, 60%, 80%, 90%, and 100% of 1RM. Each repetition was simultaneously recorded by a PUSH band and commercial linear position transducer (LPT) (GymAware [GYM]) and compared with measurements collected by a laboratory-based testing device consisting of 4 LPTs and a force plate.

Results:

Trials 2 and 3 were used for validity analyses. Combining all 120 repetitions indicated that the GYM was highly valid for assessing all criterion variables while the PUSH was only highly valid for estimations of PF (r = .94, CV = 5.4%, ES = 0.28, SEE = 135.5 N). At each relative intensity, the GYM was highly valid for assessing all criterion variables except for PP at 20% (ES = 0.81) and 40% (ES = 0.67) of 1RM. Moreover, the PUSH was only able to accurately estimate PF across all relative intensities (r = .92–.98, CV = 4.0–8.3%, ES = 0.04–0.26, SEE = 79.8–213.1 N).

Conclusions:

PUSH accuracy for determining MV, PV, MF, MP, and PP across all 6 relative intensities was questionable for the back squat, yet the GYM was highly valid at assessing all criterion variables, with some caution given to estimations of MP and PP performed at lighter loads.

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Peter Düking, Dennis-Peter Born and Billy Sperlich

Purpose:

To determine the reliability, usefulness, and validity of 3 different change-of-direction tests on a SpeedCourt (SCCODT) in team-sport players.

Methods:

For reliability and usefulness, 30 players (16 female and 14 male; age 19 ± 3 y, height 169 ± 30 cm, body mass 70 ± 11 kg) performed 3 SCCODTs differing in duration (7–45 s) on 3 occasions 1 wk apart. The total sprint times (TT) and time to change direction (TCD) were analyzed for each SCCODT. For validity, 14 players performed the Illinois Agility Test (IAT) and 505 test on a separate occasion.

Results:

TT for all SCCODTs is reliable (ICC > .79, CV < 5%), useful (TE < SWC0.5), and valid (IAT r > .71, P < .05; 505 test r > .54, P < .05). SCCODT variable TCD may be useful (TE = SWC0.5) but shows limited reliability with ICC >.65 and a CV >5%.

Conclusions:

All SCCODTs are reliable, useful, and valid to detect moderate performance changes regarding TT, with limited reliability for TCD. The quality of assessment improves when players are well familiarized with the SCCODT.

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Monoem Haddad, Anis Chaouachi, Carlo Castagna, Del P. Wong, David G. Behm and Karim Chamari

Purpose:

The session rating of perceived exertion (RPE) is a practical and non-invasive method that allows a quantification of the internal training load (TL) in individual and team sports, but no study has investigated its construct validity in martial arts. Therefore, the purpose of this study was to examine the convergent validity between the session-RPE method and two objective HR-based methods for quantifying the similar TL during a high-TL camp in young Taekwondo (TKD) athletes.

Methods:

Ten young TKD athletes (mean ± SD: age, 13.1 ± 2.4 y; body mass, 46.1 ± 12.7 kg; height, 1.53 ± 0.15 m; maximum heart rate (HRmax), 201.0 ± 8.2 bpm) participated in this study. During the training period, subjects performed 35 TKD training sessions, including two formal competitions during which RPE and HR were recorded and analyzed (308 individual training sessions). Correlation analysis was used to evaluate the convergent validity between session-RPE method and the two commonly used HR-based methods for assessing TL in a variety of training modes.

Results:

Significant relationships were found between individual session-RPE and all the HR-based TLs (r values from 0.55 to 0.90; P < .001). Significant correlations were observed in all mode of exercises practiced in TKD.

Conclusions:

This study shows that session-RPE can be considered as a valid method to assess TL in TKD.