This study examined the changes in the physiological profile of children engaged in organized sporting activity compared to a group of normally active children. Eight children (mean age 11.4 yrs) from each of four popular sports in Australia (badminton, basketball, netball, and tennis) and an equal number of nontraining children were monitored over a 12-week season. Very few differences occurred between the sporting groups and the control group. No change was reported between groups in peak oxygen uptake at the start and completion of the season. Changes occurring within each group did not consistently reflect any sport-specific characteristics over the season. Flexibility improved significantly, with an average gain of 3.76 cm in all groups except basketball players, who gained only 0.69 cm for the 12 weeks. Anaerobic power demonstrated significant improvement only within those sporting groups whose training specifically included explosive based activity. It is suggested that the active nature of the control children and use of only 12 weeks of data collection could have contributed to the limited physiological differences observed between active sporting and nonsporting children.
Geraldine Naughton and John Carlson
Geraldine Naughton and John Carlson
The heart rate intensity during 20 minutes of sports participation by circumpubertal children was monitored several times over a season. The competitive games’ mean absolute heart rates for basketball, badminton, netball, and tennis were 170, 159, 168, and 162 bts·min−1 (or 72, 75, 69, and 67% of heart rate maximum), respectively. The mean abolute heart rates for 20 minutes of participation under practice conditions for badminton, basketball, netball, and tennis were 149, 157, 144, and 135 bts·min−1, or 73, 75, 69, and 67% of heart rate maximum. At the 0.05 level of probability there was a significant difference between the heart rate intensities under competitive game and practice situations in the badminton, netball, and tennis groups. The difference between intensities of competitive games and practices was nonsignificant in the basketball players. The study concluded that participation in practice and game conditions was positive in providing the potential for a training stimulus.
Karen Soo and Geraldine Naughton
This study investigated the hydration profile of high-performance female cricket players competing at a national tournament. The profile comprised hydration monitoring (n = 18) and a questionnaire (n = 20). Our objectives were to 1) advance the understanding of fluid losses in cricket sessions across a tournament and 2) assess the hydration knowledge and practices in female cricket players. Body mass before and after each game inning was recorded in order to estimate sweat rate, sweat loss, and percentage body-mass loss. Comparisons were made between groups categorized according to level of activity during each inning. When sweat rates were estimated according to actual activity time, results were in the range of those in other female team sports but less than results from male cricket players. A range of knowledge of hydration issues was also observed. This study supports the need for individualized hydration recommendations and provides direction for further hydration education in women’s cricket.
Timothy B. Hartwig and Geraldine Naughton
Despite widespread encouragement for children to participate in sport, the efficacy of early sporting pathways remains underexplored. We compared a rotational junior-sport model combining skills from rugby, cricket, and netball with a modified games model. Motion analysis was used to quantify movement. Results revealed no differences between sporting models in relative percent time spent stationary (p = .32), walking (p = .89), jogging (p = .45), and fast running (p =.06). The rotational model had a greater number of skill-development opportunities per minute (median = 3.4) compared with the modified games model (median = 1.1, p = .001). Promising results from varied and rotational skill exposure warrant further elucidation.
John S. Carlson and Geraldine A. Naughton
The purpose of this study was to determine the anaerobic capacity of children using the maximal accumulated oxygen deficit technique (AOD). Eighteen healthy children (9 boys, 9 girls) with a mean age of 10.6 years volunteered as subjects. Peak oxygen uptake and submaximal steady-state oxygen uptake tests were conducted against progressive constant work rates on a Cybex cycle ergometer. Supramaximal work rates were predicted from the linear regression of submaximal steady-state work rates and oxygen uptakes to equal 110, 130, and 150% of peak oxygen uptake. Results indicated a significant interaction in the responses of both sexes when the accumulated oxygen deficit data were expressed in both absolute and relative terms. The profile of accumulated oxygen deficits across the three intensities indicated a downward shift in the girls responses between the 110 and 150% supramaximal tests. This trend was not evident in the boys’ responses. Intraclass correlations conducted on test-retest data indicated that compared to the boys, the reliability of the girls in the accumulated oxygen deficits in liters and ml·kg−1 was poorer.
Binh Ba Chu, David Lawson and Geraldine Naughton
This study considered the validation of the Computer Science Applications (CSA) activity monitor (model 7164) for predicting activity energy expenditure (EE). A group of 34 Vietnamese adolescents (aged 11 to 15) performed three 5-minute treadmill trials at 4.5, 6.6, and 8.8 km · h−1. Mean activity counts and heart rate (HR) were significantly changed with the three-speed trials (p > 0.05). An equation to predict EE (kcal · min−1) was developed from activity counts and body mass (BM) from the 24 random subjects in Vietnam and was validated on the remaining 10 subjects. This equation explained 72% of the variability in kcal · min−1 (adjusted R2 = 0.72, SEE = 0.91 kcal · min−1). Consistent with previous studies, the relatively high SEE indicates that the equation is more suited for groups of Vietnamese adolescents rather than individuals.
Geraldine A. Naughton and John S. Carlson
A definitive measure for assessing the energy contribution of anaerobic pathways during exhaustive exercise remains inconclusive. The accumulated oxygen deficit (AOD) has been used in several studies to estimate energy contribution. The underlying assumptions of the AOD measure have been criticized for underestimating the true contribution of anaerobic metabolism in high intensity exercise. Indeed, the AOD measure has been the subject of much controversy. Several of the physiological exercise responses of children may lead to an even greater underestimation of the anaerobic energy contribution to high intensity exercise in children than adults when AOD measures are calculated.
Darren Burgess, Geraldine Naughton and Kevin Norton
The understanding of the gap between Under 18 y (U18) and senior-level competition and the evolution of this gap in Australian Football lack a strong evidence base. Despite the multimillion dollars invested in recruitment, scientific research on successful transition is limited. No studies have compared individual players’ movement rate, game statistics and ball speed in U18 and senior competition of the Australian Football League across time. This project compared differences in player movement and ball speed between matches from senior AFL competitive matches and U18 players in the 2003 and 2009 seasons.
TrakPerformance Software and Global Positioning System (GPS) technology were used to analyze the movement of players, ball speed and game statistics. ANOVA compared the two levels of competition over time.
Observed interactions for distance traveled per minute of play (P = .009), number of sprints per minute of play (P < .001), time spent at sprint speed in the game (P < .001), time on field (P < .001), and ball speed (P < .001) were found. Subsequent analysis identified increases in movement patterns in senior AFL competition in 2009 compared with the same level of competition in 2003 and U18 players in 2003 and 2009.
Senior AFL players in 2009 were moving further, sprinting relatively more frequently, playing less time and playing at game speeds significantly greater than the same senior competition in 2003 as well as compared with both cohorts of U18 players.
Timothy B. Hartwig, Geraldine Naughton and John Searl
Investigating adolescent training loads might help us understand optimal training adaptations. GPS tracking devices and training diaries were used to quantify weekly sport and other physical activity demands placed on adolescent rugby union players and profile typical rugby training sessions.
Participants were 75 males age 14 to 18 y who were recruited from rugby teams representing 3 levels of participation: schoolboy, national representative, and a selective sports school talent squad.
Schoolboy players covered a distance of (mean ± SD) 3511 ± 836 m, representative-squad players 3576 ± 956 m, and talent-squad players 2208 ± 637 m per rugby training session. The representative squad recorded the highest weekly duration of sport and physical activity (515 ± 222 min/wk), followed by the talent squad (421 ± 211 min/week) and schoolboy group (370 ± 135 min/wk). Profiles of individual players identified as group outliers showed participation in up to 3 games and up to 11 training sessions per week, with twice the weekly load of the team averages.
Optimal participation and performance of adolescent rugby union players might be compromised by many high-load, high-impact training sessions and games and commitments to other sports and physical activities. An improved understanding of monitoring and quantifying load in adolescent athletes is needed to facilitate best-practice advice for player management and training prescription.
Darren J. Burgess and Geraldine A. Naughton
Traditional talent development pathways for adolescents in team sports follow talent identification procedures based on subjective games ratings and isolated athletic assessment. Most talent development models are exclusive rather than inclusive in nature. Subsequently, talent identification may result in discontentment, premature stratification, or dropout from team sports. Understanding the multidimensional differences among the requirements of adolescent and elite adult athletes could provide more realistic goals for potential talented players. Coach education should include adolescent development, and rewards for team success at the adolescent level should reflect the needs of long-term player development. Effective talent development needs to incorporate physical and psychological maturity, the relative age effect, objective measures of game sense, and athletic prowess. The influences of media and culture on the individual, and the competing time demands between various competitions for player training time should be monitored and mediated where appropriate. Despite the complexity, talent development is a worthy investment in professional team sport.