Incorporating perceptual decision-making training into high-intensity interval training for Australian football umpires.

Existing methods for developing decision-making skill for Australian football umpires separate the physical and perceptual aspects of their performance. This study aimed to determine the efficacy of incorporating video-based decision-making training during high-intensity interval training sessions, specific for Australian football umpires. 20 amateur Australian football umpires volunteered to participate in a randomised control trial. Participants completed an 8-week training intervention in a conditioning only (CON; n=7), combined video-based training and conditioning (COM; n=7), or separated conditioning and video-based training (SEP; n=6) group. Preliminary and post-testing involved a Yo-Yo Intermittent Recovery Test (Yo-YoIR1), and 10x300m run test with an Australian football specific video-based decision-making task. Overall, changes in decision-making accuracy following the intervention were unclear between groups. SEP was possibly beneficial compared to COM in Yo-YoIR1 performance, whereas CON was likely beneficial compared to COM in 10x300m sprint performance. There was no additional benefit to completing video-based training, whether combined with, or separate to physical training, suggesting that this was not an optimal training method. For video-based training to be an effective decision-making tool, detailed feedback should be incorporated into training. It is recommended that longer conditioning and video-based training interventions be implemented to determine training effectiveness.

Cycling Power Profile Characteristics of National-Level Junior Triathletes.

Stevens, CJ, Bennett, KJM, Novak, AR, Kittel, AB, and Dascombe, BJ. Cycling power profile characteristics of national-level junior triathletes. J Strength Cond Res 33(1): 197-202, 2019-With the draft-legal rule recently introduced to junior triathlon competition, it has become difficult to assess cycling performance through race results. Therefore, this study assessed the cycling power profile characteristics of national-level junior triathletes to assist with physical assessment and program design. Thirteen male (17.0 ± 1.0 years) and 11 female (17.2 ± 1.3 years) national-level junior triathletes completed a cycling power profile that consisted of maximal intervals that lasted 6, 15, 30, 60, 240, and 600 seconds in duration. Each power profile was completed on a LeMond ergometer using the subject's own bicycle, with power output and cadence recorded for all intervals. Mean power output values for males (783 ± 134, 768 ± 118, 609 ± 101, 470 ± 65, 323 ± 38, and 287 ± 34 W) were significantly (p ≤ 0.05) higher than those for females (554 ± 92, 510 ± 89, 437 ± 75, 349 ± 56, 248 ± 39, and 214 ± 37 W) across all intervals, respectively. Peak power output values for males across the 6- and 15-second intervals (1,011 ± 178 and 962 ± 170 W) were also significantly higher than those for females (674 ± 116 and 624 ± 114 W), respectively (p ≤ 0.05). Developing junior triathletes should aim to increase their capacity across the power profile above the mean values listed. Athletes should further aim to have power outputs equal to that of the best performers and beyond to ensure that they can meet the demands of any competition situation.

Running performance in the heat is improved by similar magnitude with pre-exercise cold-water immersion and mid-exercise facial water spray.

This investigation compared the effects of external pre-cooling and mid-exercise cooling methods on running time trial performance and associated physiological responses. Nine trained male runners completed familiarisation and three randomised 5 km running time trials on a non-motorised treadmill in the heat (33°C). The trials included pre-cooling by cold-water immersion (CWI), mid-exercise cooling by intermittent facial water spray (SPRAY), and a control of no cooling (CON). Temperature, cardiorespiratory, muscular activation, and perceptual responses were measured as well as blood concentrations of lactate and prolactin. Performance time was significantly faster with CWI (24.5 ± 2.8 min; P = 0.01) and SPRAY (24.6 ± 3.3 min; P = 0.01) compared to CON (25.2 ± 3.2 min). Both cooling strategies significantly (P < 0.05) reduced forehead temperatures and thermal sensation, and increased muscle activation. Only pre-cooling significantly lowered rectal temperature both pre-exercise (by 0.5 ± 0.3°C; P < 0.01) and throughout exercise, and reduced sweat rate (P < 0.05). Both cooling strategies improved performance by a similar magnitude, and are ergogenic for athletes. The observed physiological changes suggest some involvement of central and psychophysiological mechanisms of performance improvement.

The Effectiveness of Above Real Time Training for Developing Decision-Making Accuracy in Australian Football Umpires.

Purpose: The aim of this study was to investigate the effects of an above real-time video-based training intervention on Australian football umpire decision-making skill. Methods: Three groups completed two testing sessions, either side of a five-week, video-based training intervention either in real time (100% speed), above real time (150% speed) or control (no training) condition. Testing included two parts: resting included 25 video clips 10 of Australian football match footage, presented in real time with participants resting; exercise included a separate 25 clips also presented at real time, during a 10 × 300 m run test. Tests were repeated within two weeks following training. Results: Decision-making accuracy significantly improved (p = .043) for the real time training group in the exercise test. There were no improvements in control or above real-time training groups in the exercise test. No significant differences were observed for decision-making accuracy in the 15 resting test for all groups. Conclusion: Above real-time video may not develop decision-making skills more effectively than real-time video for amateur Australian football umpires. For this cohort, the faster presentation of video may result in the umpires missing important perceptual cues. Real-time video-based training appears to be more beneficial for amateur officials than 150% above real-time speed.

Transfer of 360° virtual reality and match broadcast video-based tests to on-field decision-making.

This study aimed to assess the level of transfer of two reliable and valid video modes to in-game decision-making performance. Two video-based tests of 25 clips each (360°VR and match broadcast vision) assessed off-field decision-making accuracy in elite Australian football umpires (n=21). Game performance was assessed across four games for each participant, classified into two groups based on this measure; "highly skilled" or 'skilled'. Decision-making was assessed for correct, missed and unwarranted decisions in video-based tests and in-game assessments. Independent t-tests analysed differences between highly skilled and skilled in-game decision-makers for each test. Correlations also compared experience and in-game with video-based test decision-making performance. For both video-based tests, there were no significant differences between highly skilled and skilled in-game decision-makers, nor any significant correlations. Officials who made less unwarranted decisions in-game (highly skilled) made significantly less unwarranted decisions in the match broadcast test. There was a significant correlation between experience and 360°VR correct decision-making. Neither video-based test had the sensitivity to discriminate between elite officials, potentially due to the third-person perspective (match broadcast task) or sub-elite players presented (360°VR). Optimising the representativeness of off-field tasks through including similar constraints to performance environments is an important consideration for researchers and practitioners.

Using 360° virtual reality as a decision-making assessment tool in sport.

OBJECTIVES: To examine the reliability, construct validity and ecological validity of 360° VR and match broadcast footage for off-field decision-making assessment in Australian football umpires. DESIGN: Validation assessments with test re-test reliability. METHODS: Two video-based tests of 60 clips each were developed to assess Australian football umpire decision-making, including 360° video of small-sided Australian football games and match broadcast footage of AFL games. Elite (n = 13) and amateur (n = 15) umpires participated in two testing sessions, in a randomised, counterbalanced design. Test re-test reliability was assessed using Cohen's Kappa for individual clips and Intraclass Correlation Coefficients for test scores. Video tests were assessed for construct validity. Ecological validity of the decision-making processes was assessed for each method. RESULTS: 31 clips met the minimum Kappa criteria for the 360° VR test and 28 clips for match broadcast. Results indicated strong reliability for the 360° VR (ICC = 0.89) and match broadcast (ICC = 0.89) tests. For both video modes, elite umpires performed significantly better in decision-making accuracy than amateur (p < 0.05). For ecological validity of the decision-making processes, 360° VR was rated significantly higher than match broadcast vision (p < 0.05) overall. CONCLUSIONS: This is the first study to examine the reliability and validity of 360° VR footage as an off-field decision-making assessment tool in sport. As match broadcast vision is commonly used to assess decision-making in athletes and officials, results suggest that 360° VR is also an appropriate assessment tool. Although both video modes demonstrate similar reliability and construct validity, 360° VR was considered more specific to in-game decision-making processes, suggesting stronger ecological validity.

Acute physiological and perceptual responses to wearing additional clothing while cycling outdoors in a temperate environment:A practical method to increase the heat load.

This investigation assessed the acute physiological and perceptual responses to wearing additional clothing during outdoor cycling to determine if this strategy could increase the heat load while training in temperate environments. Seven male cyclists (age: 32 ± 13 y, height: 179 ± 10 cm, body mass: 74 ± 10 kg, body fat percentage: 10.3 ± 1.0%) completed 2 randomized outdoor (∼17°C and ∼82% RH), 80 min cycling sessions at moderate-hard intensities (CR10 RPE = 3-5). They wore spandex shorts and a short sleeve top (CON) or additional clothing including full-length spandex pants and a 'winter' cycling jacket and gloves (AC). Core temperature, heart rate, sweat rate, thermal sensation and thermal comfort were measured across the trials. Moderate increases were observed in AC vs. CON for the change in mean core temperature (0.4 ± 0.3°C, effect size, ES = 1.16 ± 0.55), change in maximum core temperature (0.5 ± 0.3°C, ES = 1.07 ± 0.48) and sweat rate (0.24 ± 0.16 L . h-1, ES = 1.04 ± 0.59). A small increase in mean heart rate (3 ± 3 bpm, ES = 0.32 ± 0.28) was observed as well as a 'very likely' (percentage difference = 22.4 ± 7.1) and 'most likely' (percentage difference = 42.9 ± 11.9) increase in thermal sensation and thermal comfort, respectively, in AC vs. CON. Dressing in additional clothing while cycling outdoors in a temperate environment increased physiological strain and sensations of warmth and discomfort. Training in additional clothing during outdoor cycling represents a practical alternative to increasing the heat load of a training session.