Secular changes in anaerobic fitness test performance in healthy 6- to 17-year-old Australasians were examined by meta-analysis of 232,564 power- and speed-test performances between 1960 and 2002. Overall, power-test performance improved at a rate of +0.05% [95% confidence interval (CI) = +0.01% to +0.09%] per annum, and speed at +0.04% (CI = +0.02% to +0.06%) per annum. Results indicate that anaerobic-fitness-test performances have remained relatively stable in Australasian children and adolescents in recent decades.
Grant R. Tomkinson, Michael J. Hamlin and Timothy S. Olds
Grant R. Tomkinson, Justin J. Lang, Joel Blanchard, Luc A. Léger and Mark S. Tremblay
Cardiorespiratory fitness (CRF) is a good summative measure of the body’s ability to perform continuous, rhythmic, dynamic, large-muscle group physical activity, and exercise. In children, CRF is meaningfully associated with health, independent of physical activity levels, and it is an important determinant of sports and athletic performance. Although gas-analyzed peak oxygen uptake is the criterion physiological measure of children’s CRF, it is not practical for population-based testing. Field testing offers a simple, cheap, practical alternative to gas analysis. The 20-m shuttle run test (20mSRT)—a progressive aerobic exercise test involving continuous running between 2 lines 20 m apart in time to audio signals—is probably the most widely used field test of CRF. This review aims to clarify the international utility of the 20mSRT by synthesizing the evidence describing measurement variability, validity, reliability, feasibility, and the interpretation of results, as well as to provide future directions for international surveillance. The authors show that the 20mSRT is an acceptable, feasible, and scalable measure of CRF and functional/exercise capacity, and that it has moderate criterion validity and high to very high reliability. The assessment is pragmatic, easily interpreted, and results are transferable to meaningful and understandable situations. The authors recommend that CRF, assessed by the 20mSRT, be considered as an international population health surveillance measure to provide additional insight into pediatric population health.
Leon Straker, Erin Kaye Howie, Dylan Paul Cliff, Melanie T. Davern, Lina Engelen, Sjaan R. Gomersall, Jenny Ziviani, Natasha K. Schranz, Tim Olds and Grant Ryan Tomkinson
Australia has joined a growing number of nations that have evaluated the physical activity and sedentary behavior status of their children. Australia received a “D minus” in the first Active Healthy Kids Australia Physical Activity Report Card.
An expert subgroup of the Australian Report Card Research Working Group iteratively reviewed available evidence to answer 3 questions: (a) What are the main sedentary behaviors of children? (b) What are the potential mechanisms for sedentary behavior to impact child health and development? and (c) What are the effects of different types of sedentary behaviors on child health and development?
Neither sedentary time nor screen time is a homogeneous activity likely to result in homogenous effects. There are several mechanisms by which various sedentary behaviors may positively or negatively affect cardiometabolic, neuromusculoskeletal, and psychosocial health, though the strength of evidence varies. National surveillance systems and mechanistic, longitudinal, and experimental studies are needed for Australia and other nations to improve their grade.
Despite limitations, available evidence is sufficiently convincing that the total exposure and pattern of exposure to sedentary behaviors are critical to the healthy growth, development, and wellbeing of children. Nations therefore need strategies to address these common behaviors.
Mark S. Tremblay, Joel D. Barnes, Silvia A. González, Peter T. Katzmarzyk, Vincent O. Onywera, John J. Reilly, Grant R. Tomkinson and the Global Matrix 2.0 Research Team
The Active Healthy Kids Global Alliance organized the concurrent preparation of Report Cards on the physical activity of children and youth in 38 countries from 6 continents (representing 60% of the world’s population). Nine common indicators were used (Overall Physical Activity, Organized Sport Participation, Active Play, Active Transportation, Sedentary Behavior, Family and Peers, School, Community and the Built Environment, and Government Strategies and Investments), and all Report Cards were generated through a harmonized development process and a standardized grading framework (from A = excellent, to F = failing). The 38 Report Cards were presented at the International Congress on Physical Activity and Public Health in Bangkok, Thailand on November 16, 2016. The consolidated findings are summarized in the form of a Global Matrix demonstrating substantial variation in grades both within and across countries. Countries that lead in certain indicators often lag in others. Average grades for both Overall Physical Activity and Sedentary Behavior around the world are D (low/poor). In contrast, the average grade for indicators related to supports for physical activity was C. Lower-income countries generally had better grades on Overall Physical Activity, Active Transportation, and Sedentary Behaviors compared with higher-income countries, yet worse grades for supports from Family and Peers, Community and the Built Environment, and Government Strategies and Investments. Average grades for all indicators combined were highest (best) in Denmark, Slovenia, and the Netherlands. Many surveillance and research gaps were apparent, especially for the Active Play and Family and Peers indicators. International cooperation and cross-fertilization is encouraged to address existing challenges, understand underlying determinants, conceive innovative solutions, and mitigate the global childhood inactivity crisis. The paradox of higher physical activity and lower sedentary behavior in countries reporting poorer infrastructure, and lower physical activity and higher sedentary behavior in countries reporting better infrastructure, suggests that autonomy to play, travel, or chore requirements and/or fewer attractive sedentary pursuits, rather than infrastructure and structured activities, may facilitate higher levels of physical activity.
Natasha K. Schranz, Timothy Olds, Roslyn Boyd, John Evans, Sjaan R. Gomersall, Louise Hardy, Kylie Hesketh, David R. Lubans, Nicola D. Ridgers, Leon Straker, Stewart Vella, Jenny Ziviani and Grant R. Tomkinson
Two years on from the inaugural Active Healthy Kids Australia (AHKA) Physical Activity Report Card, there has been little to no change with the majority of Australian children still insufficiently active.
The 2016 AHKA Report Card was developed using the best available national- and state-based physical activity data, which were evaluated by the AHKA Research Working Group using predetermined weighting criteria and benchmarks to assign letter grades to the 12 Report Card indicators.
In comparison with 2014, Overall Physical Activity Levels was again assigned a D- with Organized Sport and Physical Activity Participation increasing to a B (was B-) and Active Transport declining to a C- (was C). The settings and sources of influence again performed well (A- to a C+), however Government Strategies and Investments saw a decline (C+ to a D). The traits associated with physical activity were also graded poorly (C- to a D).
Australian youth are insufficiently active and engage in high levels of screen-based sedentary behaviors. While a range of support structures exist, Australia lacks an overarching National Physical Activity Plan that would unify the country and encourage the cultural shift needed to face the inactivity crisis head on.