Are today's children and adolescents physically fitter than their peers from the past? Both scholarly and lay opinion is divided on this question. Using a meta-analytical strategy, this thesis comprehensively quantifies the secular trends in the fitness test performance of Australasian children and adolescents, more specifically, the secular trends in power, speed and cardiovascular endurance test performance. It also provided a global context for the Australasian evolution. / The thesis starts by charting the global evolution of the fitness test performance of children and adolescents. To do this, an extensive literature search was undertaken to identify as many studies as possible, which explicitly commented on secular trends in fitness test performance. Only studies reporting fitness test performances at a minimum of two time points on comparable populations were reviewed. Although numerous studies reporting on the fitness test performances of children and adolescents exist, many only make informal comparisons with past results, with very few quantifying these comparisons. Data were available from 54 studies, on approximately 26 million children and adolescents from 29 countries, tested between 1911 and 2001. Most of these studies were very localised in time and space, and only when put together did they paint a global picture. Globally, power and speed test performances have evolved little over time, while cardiovascular endurance test performances have been declining systematically since 1970. The distributional characteristics of performance on fitness tests have changed over time, with increasing skew in cardiovascular endurance tests, but little change in power and speed tests. / After painting the global picture, the focus shifts to the Australian literature. This thesis used a more fine-grained-meta-analytical strategy, considering every suitable report, even if measured at a single point in time, to build up a picture of secular trends in fitness test performance of children and adolescents from Australia and New Zealand. A total of 56 Australasian studies were used to quantify the patterns of change of performance on fitness tests. Secular trends in mean test performance, and in the variability of test performance, were determined on 393,454 Australasians aged 6-17 years, tested in the period 1960-2002. Australasian children and adolescents follow the global model. The results show that there has been a sharp decline in the cardiovascular endurance test performance of Australasian children and adolescents in recent decades, with little change in tests of power and speed. There have also been increases in the variability of performance on fitness tests over time, with increases most marked in cardiovascular endurance tests. / Possible causes, correlates and mechanisms of change are discussed. It seems likely that changed in fitness test performances reflect physiological decrements, largely resulting from energy imbalance subsequent to changes in behavioural patterns (e.g. increases in levels of screen-based inactivity, reductions in incidental physical activity and increased access to energy-dense food). / Thesis (PhDHumanMovement)--University of South Australia, 2004.
| Identifer | oai:union.ndltd.org:ADTP/267560 |
| Creators | Tomkinson, Grant Rhyan. |
| Source Sets | Australiasian Digital Theses Program |
| Language | English |
| Detected Language | English |
| Rights | copyright under review |
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