Professional rugby league (RL) football is a contact sport involving repeated collisions and high-intensity efforts; both training and competition involve high energy expenditure. The present review summarizes and critiques the available literature relating the physiological demands of RL to nutritional requirements and considers potential ergogenic supplements that could improve players’ physical capacity, health, and recovery during the preparatory and competition phases of a season. Although there may not be enough data to provide RL-specific recommendations, the available data suggest that players may require approximately 6–8 g·kg−1·day−1 carbohydrate, 1.6–2.6 g·kg−1·day−1 protein, and 0.7–2.2 g·kg−1·day−1 fat, provided that the latter also falls within 20–35% of total energy intake. Competition nutrition should maximize glycogen availability by consuming 1–4 g/kg carbohydrate (∼80–320 g) plus 0.25 g/kg (∼20–30 g) protein, 1–4 hr preexercise for 80–120 kg players. Carbohydrate intakes of approximately 80–180 g (1.0–1.5 g/kg) plus 20–67 g protein (0.25–0.55 g/kg) 0–2 hr postexercise will optimize glycogen resynthesis and muscle protein synthesis. Supplements that potentially improve performance, recovery, and adaptation include low to moderate dosages of caffeine (3–6 mg/kg) and ∼300 mg polyphenols consumed ∼1 hr preexercise, creatine monohydrate “loading” (0.3 g·kg−1·day−1) and/or maintenance (3–5 g/day), and beta-alanine (65–80 mg·kg−1·day−1). Future research should quantify energy expenditures in young, professional male RL players before constructing recommendations.
Vincent G. Kelly, Liam S. Oliver, Joanna Bowtell, and David G. Jenkins
Stamatis Agiovlasitis, Jooyeon Jin, and Joonkoo Yun
The authors examined if body mass index (BMI), weight, and height across age groups differ between adults with Down syndrome (DS) and adults with intellectual disability but without DS. They conducted secondary analyses of cross-sectional data from 45,803 individuals from the United States from 2009 to 2014 of the National Core Indicators Adult Consumer Survey across five age groups: 18–29, 30–39, 40–49, 50–59, and 60+ years. For both men and women with DS, BMI and weight increased between the 18- to 29- and the 30- to 39-year age groups and decreased thereafter. For both men and women with intellectual disability, BMI and weight increased between the 18- to 29- and the 30- to 39-year age groups, stayed about the same until the 50- to 59-year age group, and decreased thereafter. Height demonstrated a small but significant decrease with older age in all groups. These cross-sectional comparisons indicate that BMI and weight may start decreasing at a younger age in adults with DS than in adults with intellectual disability.
David Suárez-Iglesias, Rubén Dehesa, Aaron T. Scanlan, José A. Rodríguez-Marroyo, and Alejandro Vaquera
Purpose: Games-based drills (GBD) are the predominant form of training stimulus prescribed to male and female basketball players. Despite being readily manipulated during GBD, the impact of defensive strategy on the sex-specific demands of GBD remains unknown. Therefore, the aim of this study was to quantify and compare the heart-rate (HR) responses experienced during 5v5 GBD using different defensive strategies (man-to-man defense vs zone defense [ZD] formations) according to player sex. Method: HR was recorded in 11 professional male and 10 professional female basketball players while performing 5v5 GBD with different defensive strategies (man-to-man defense or ZD). HR-based training load was also calculated using the summated heart-rate zones model. Results: During man-to-man defense, mean HR (
Teri A. Todd, Keely Ahrold, Danielle N. Jarvis, and Melissa A. Mache
Children with autism spectrum disorder (ASD) typically demonstrate deficits in gross motor skills such as the overhand throw. It has not been determined whether such deficits persist into adulthood. Therefore, the purpose of this study was to examine the kinematics and developmental level of overhand throws among young adults with and without ASD. Three-dimensional motion-capture data were collected during overhand throwing trials performed by 20 college students (10 students with ASD). Individuals with ASD demonstrated similar throw duration, stride length, and step width but a longer acceleration phase and slower ball velocity than individuals without ASD. Young adults with ASD also performed the overhand throw with less developmental proficiency than those without ASD. Specifically, individuals with ASD exhibited developmental deficits in the backswing and composite throwing score. Motor skill interventions for individuals with ASD should address throwing skills, with a particular focus on the preparatory phase of the overhand throw.
Kerri L. Staples, E. Andrew Pitchford, and Dale A. Ulrich
The Test of Gross Motor Development is among the most commonly used measures of gross motor competency in children. An important attribute of any developmental assessment is its sensitivity to detect change. The purpose of this study was to examine the instructional sensitivity of the Test of Gross Motor Development—third edition (TGMD-3) performance criteria to changes in performance for 48 children (age 4–7 years) with and without Down syndrome following 10 weeks of physical education. Paired t tests identified significant improvements for all children on locomotor (p < .01) and ball skills (p < .01). These significant differences were associated with moderate to large effect sizes. SEM was low relative to the maximum raw score for each subtest, indicating high confidence in the scores. These findings provide evidence that the TGMD-3 is sensitive to change in performance for children with and without Down syndrome.
Marte Bentzen, Danielle Alexander, Gordon A. Bloom, and Göran Kenttä
The purpose of this scoping review was to provide a broad overview of the literature pertaining to parasport coaches, including information regarding the size and scope of research, the populations and perspectives obtained, and the type of methods used to conduct the research. Data were collected and analyzed using a six-stage framework for conducting scoping reviews. The results revealed that the majority of articles were based on interviews, and an overwhelming majority of the participants were men coaching at the high-performance level in North America. Three of the most frequent topics were becoming a parasport coach, being a parasport coach, and having general parasport coaching knowledge. Articles ranged in date from 1991 to 2018, with 70% of empirical articles published from 2014 onward, indicating an emerging interest in this field of research. This review has the potential to advance the science and practice of parasport coaching at all levels.
Gennaro Boccia, Marco Cardinale, and Paolo Riccardo Brustio
Purpose: To quantify how many of the top 50 under-18 (U18) sprinters in the world managed to become top 50 ranked as adult competitors. The authors also described the career trajectory of athletes ranked in the top 50 during either U18 or senior category. Methods: A total of 4924 male and female athletes competing in sprint races and ranked in the International Association of Athletics Federations (now World Athletics) lists in any of the seasons between the 2000 and 2018 were included in the study. The athletes ranked in the top 50 positions of all-time lists during U18, senior, or both categories were analyzed. Results: Only 17% of the male and 21% of the female top 50 ranked U18 managed to become top 50 ranked senior athletes. The top 50 ranked senior athletes consistently produced yearly larger improvements during late adolescence and early adulthood compared with those who ranked in the top 50 at U18. Furthermore, top 50 ranked senior athletes reached their peak performance later compared with the top 50 ranked only in U18. Conclusions: This study confirms that early success in track and field is not a good predictor of success at senior level in sprinting events. The yearly performance improvements and their tracking provide the most suitable approach to identify athletes more likely to succeed as elite performers in adulthood. The authors hope that the results of this study can provide useful comparative data and reference criteria for talent-identification and -development programs.
Katie E. McGibbon, David B. Pyne, Laine E. Heidenreich, and Robin Pla
Purpose: Pacing, or the distribution of energy expenditure, is particularly important in swimming; however, there is limited research examining pacing profiles in long-distance freestyle events. This study aimed to characterize the pacing profiles of elite male 1500-m freestyle swimmers using a novel method to provide a detailed analysis of different race segments. Methods: The race data for 327 male 1500-m freestyle long-course races between 2010 and 2019 were analyzed retrospectively. The raw 50-m split times for each lap were converted to a percentage of overall race time. The races were classified as a fast-, average-, or slow-start strategy (laps 1–2); as an even, negative, or positive pacing strategy (laps 3–28); and as a fast-, average-, or slow-finish strategy (laps 29–30) to give an overall pacing profile. Results: Slow- and average-start strategies were associated with faster overall 1500-m times than a fast-start strategy (mean = −21.2 s; 90% confidence interval, −11.4 to −32.3 s, P = .00). An even pacing strategy in laps 3 to 28 yielded faster overall 1500-m times than a positive pacing strategy (−8.4 s, −3.9 to −13.0 s, P = .00). The overall 1500-m times did not differ substantially across the finish strategies (P = .99). The start strategy differed across age groups and nationalities, where younger swimmers and swimmers from Australia and Great Britain typically spent a lower percentage of race time in laps 1 to 2 (faster start strategy; −0.10%, −0.01% to −0.23%, P ≤ .02). Conclusion: Adopting a relatively slower start strategy helps conserve energy for the latter stages of a 1500-m freestyle race.
Dionne A. Noordhof, Sjur J. Øfsteng, Linnea Nirenberg, Daniel Hammarström, Joar Hansen, Bent R. Rønnestad, and Øyvind Sandbakk
Performance-determining variables are usually measured from a rested state and not after prolonged exercise, specific to when athletes compete for the win in long-distance events. Purpose: (1) To compare cross-country skiing double-poling (DP) performance and the associated physiological and biomechanical performance-determining variables between a rested state and after prolonged exercise and (2) to investigate whether the relationship between the main performance-determining variables and DP performance is different after prolonged submaximal DP than when tested from a rested state. Methods: Male cross-country skiers (N = 26) performed a blood lactate profile test and an incremental test to exhaustion from a rested state on day 1 (D1; all using DP) and after 90-minute submaximal DP on day 2 (D2). Results: The DP performance decreased following prolonged submaximal DP (D1: peak speed = 15.33–20.75 km·h−1, median = 18.1 km·h−1; D2: peak speed = 13.68–19.77 km·h−1, median = 17.8 km·h−1; z = −3.96, P < .001, effect size r = −.77), which coincided with a reduced submaximal gross efficiency and submaximal and peak cycle length, with no significant change in peak oxygen uptake (P = .26, r = .23). The correlation coefficient between D1 cycle length at 12 km·h−1 and D2 performance is significantly smaller than the correlation coefficient between D2 cycle length at 12 km·h−1 and D2 performance (P = .033), with the same result being found for peak cycle length (P < .001). Conclusions: The reduced DP performance after prolonged submaximal DP coincided with a reduced submaximal gross efficiency and shorter peak cycle length. The results indicate that performance-determining variables could be determined after prolonged exercise to gain more valid insight into long-distance DP performance.