This study sought to explore the type of fundamental movement skills (FMS) performed during Active Video Game (AVG) play, as well as the frequency with which these FMS are performed. In addition, this study aimed to determine the relationship between FMS performance and energy expenditure during 15 min of AVG play across two Microsoft Xbox Kinect AVGs. Fundamental movement skills were observed via video by two raters and energy expenditure derived using Actiheart monitors in children aged 10–15 years. Six different FMS were observed during AVG play with differences in the number of FMS performed between the two AVGs. The overall energy expended (Joules/kg/minute), however, was similar between the AVGs, suggesting the frequency of FMS did not influence overall energy expended during play. The movements observed during AVG play that possibly accounted for the energy expenditure, were not of a quality that could be classified as FMS. This research demonstrates that children playing these two games have the opportunity to repeatedly perform mostly two FMS, namely jumping and dodging. The goal of the AVGs, however, could be achieved with generalized movements that did not always meet the criteria to be classified as a FMS.
Ashleigh Thornton, Brendan Lay, Michael Rosenberg, Joanna Granich and Rebecca Braham
Greg Henry, Brian Dawson, Brendan Lay and Warren Young
To study the validity of a video-based reactive agility test in Australian footballers.
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).
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).
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.
David Whiteside, Bruce Elliott, Brendan Lay and Machar Reid
The importance of the flat serve in tennis is well documented, with an abundance of research evaluating the service technique of adult male players. Comparatively, the female and junior serves have received far less attention. Therefore, the aims of this study were to quantify the flat serve kinematics in elite prepubescent, pubescent, and postpubescent female tennis players. Full body, racket, and ball kinematics were derived using a 22-camera Vicon motion capture system. Racket velocity was significantly lower in the prepubescent group than in the two older groups. In generating racket velocity, the role of the serving arm appears to become more pronounced after the onset of puberty, whereas leg drive and “shoulder-over-shoulder” rotation mature even later in development. These factors are proposed to relate to strength deficits and junior players’ intentions to reduce the complexity of the skill. Temporally, coupling perception (cues from the ball) and action (body movements) are less refined in the prepubescent serve, presumably reducing the “rhythm” (and dynamism) of the service action. Practically, there appears scope for equipment scaling to preserve kinematic relevance between the junior and senior serve and promote skill acquisition.
Jacinta M. Saldaris, Grant J. Landers and Brendan S. Lay
Purpose: To examine the effects of precooling via crushed ice ingestion on cognitive function during exercise in the heat. Methods: Eleven active men ingested either 7 g·kg−1 of crushed ice (ICE) or thermoneutral water (CON) 30 minutes before running 90 minutes on a treadmill at a velocity equivalent to 65% VO2peak in hot and humid conditions (35.0°C [0.5°C], 53.1% [3.9%] relative humidity). Participants completed 3 cognitive tasks to investigate decision making (8-choice reaction time [CRT]), working memory (serial seven [S7]), and executive control (color multisource interference task [cMSIT]) on arrival, after precooling, and after running. Results: Precooling significantly decreased preexercise core (T core) and forehead skin temperature in ICE compared with CON, respectively (T core 0.8°C [0.4°C], –0.2°C [0.1°C]; T head –0.5°C [0.4°C], 0.2°C [0.8°C]; P ≤ .05). Postrun, ICE significantly reduced errors compared with CON for CRT (P ≤ .05; d = 0.90; 90% confidence interval, 0.13–1.60) and S7 (P ≤ .05; d = 1.05; 90% confidence interval, 0.26–1.75). Thermal sensation was lower after precooling with ICE (P ≤ .05), but no significant differences were recorded between conditions for cMSIT errors, skin temperature, heart rate, or ratings of perceived exertion or perceived thirst (P > .05). Conclusions: Precooling via ICE maintained cognitive accuracy in decision making and working memory during exercise in the heat. Thus, ICE may have the potential to improve sporting performance by resisting deleterious effects of exercise in a hot and humid environment on cognitive function.