A conceptual model of physical performance in Australian Football
- Authors: Mooney, Mitchell
- Date: 2013
- Type: Text , Thesis , PhD
- Full Text:
- Description: Objective: The objective of this project was to identify the relative influence of valid physical parameters to elite Australian Football performance. Methods: Data was collected on match performance variables (i.e. coaches’ votes, number of ball disposals, champion data rank), match exercise intensity measures (m∙min-1, m∙min-1 above and below 15 km∙h-1 and Load™∙min-1) and physical capacities (yo-yo intermittent recovery test level 2, maximum oxygen uptake, running economy, relative aerobic intensity, maximal aerobic speed and maximal accumulated oxygen deficit) on elite and recreational Australian footballers. These variables were modelled to determine the logical sequence and relative importance towards match performance. Results: The results indicate a sequential physical path to Australian Football performance. The yo-yo intermittent recovery test (level 2) performance influenced match exercise intensity (m∙min-1 >15 km∙h-1& Load™∙min-1) which in turn, affected Australian Football performance (number of ball disposals and coaches’ votes). This sequence was altered by experience, playing position and neuromuscular fatigue. The number of interchange rotations also influenced match exercise intensity throughout the match. Furthermore, the yo-yo intermittent recovery test (level 2) was found to be determined by a complex interaction of physical capacities. However, yo-yo intermittent recovery (level 2) performance was most influenced by maximum oxygen uptake, relative aerobic intensity and maximum aerobic speed. Conclusion: This dissertation showed Australian Football performance is a complex and dynamic system influenced by many variables interacting with each other in a sequential path. Sports scientists and coaches may utilise this information as a framework to evaluate Australian Football performance matches.
- Description: Doctor of Philosophy
- Authors: Mooney, Mitchell
- Date: 2013
- Type: Text , Thesis , PhD
- Full Text:
- Description: Objective: The objective of this project was to identify the relative influence of valid physical parameters to elite Australian Football performance. Methods: Data was collected on match performance variables (i.e. coaches’ votes, number of ball disposals, champion data rank), match exercise intensity measures (m∙min-1, m∙min-1 above and below 15 km∙h-1 and Load™∙min-1) and physical capacities (yo-yo intermittent recovery test level 2, maximum oxygen uptake, running economy, relative aerobic intensity, maximal aerobic speed and maximal accumulated oxygen deficit) on elite and recreational Australian footballers. These variables were modelled to determine the logical sequence and relative importance towards match performance. Results: The results indicate a sequential physical path to Australian Football performance. The yo-yo intermittent recovery test (level 2) performance influenced match exercise intensity (m∙min-1 >15 km∙h-1& Load™∙min-1) which in turn, affected Australian Football performance (number of ball disposals and coaches’ votes). This sequence was altered by experience, playing position and neuromuscular fatigue. The number of interchange rotations also influenced match exercise intensity throughout the match. Furthermore, the yo-yo intermittent recovery test (level 2) was found to be determined by a complex interaction of physical capacities. However, yo-yo intermittent recovery (level 2) performance was most influenced by maximum oxygen uptake, relative aerobic intensity and maximum aerobic speed. Conclusion: This dissertation showed Australian Football performance is a complex and dynamic system influenced by many variables interacting with each other in a sequential path. Sports scientists and coaches may utilise this information as a framework to evaluate Australian Football performance matches.
- Description: Doctor of Philosophy
Arsenic mobilization in a seawater inundated acid sulfate soil
- Johnston, Scott, Keene, Annabelle, Burton, Edward, Bush, Richard, Sullivan, Leigh, McElnea, Angus, Ahern, Col, Smith, C. Douglas, Powell, Bernard, Hocking, Rosalie
- Authors: Johnston, Scott , Keene, Annabelle , Burton, Edward , Bush, Richard , Sullivan, Leigh , McElnea, Angus , Ahern, Col , Smith, C. Douglas , Powell, Bernard , Hocking, Rosalie
- Date: 2010
- Type: Text , Journal article
- Relation: Environmental Science and Technology Vol. 44, no. 6 (2010), p. 1968-1973
- Full Text:
- Reviewed:
- Description: Tidal seawater inundation of coastal acid sulfate soils can generate Fe- and SO4-reducing conditions in previously oxicacidic sediments, This creates potential for mobilization of As during the redox transition. We explore the consequences for As by investigating the hydrology, porewater geochemistry, solid-phase speciation, and mineralogical partitioning of As across two tidal fringe toposequences. Seawater inundation induced a tidally controlled redox gradient. Maximum porewater As (∼400μg/L) occurred in the shallow (<1 m), intertidal, redox transition zone between Fe-oxidizing and SO 4-reducing conditions. Primary mechanisms of As mobilization include the reduction of solid-phase As(V) to As(III), reductive dissolution of As(V)-bearing secondary Fe(III) minerals and competitive anion desorption. Porewater As concentrations decreased in the zone of contemporary pyrite reformation, Oscillating hydraulic gradients caused by tidal pumping promote upward advection of As and Fe2+-enriched porewater in the intertidal zone, leading to accumulation of As(V)-enriched Fe(III) (hydr)oxides at the oxic sediment-water interface. While this provides a natural reactive-Fe barrier, it does not completely retard the flux of porewater As to overtopping surface waters. Furthermore, the accumulated Fe minerals may be prone to future reductive dissolution, A conceptual model describing As hydro-geochemical coupling across an intertidal fringe is presented. © 2010 American Chemical Society.
- Authors: Johnston, Scott , Keene, Annabelle , Burton, Edward , Bush, Richard , Sullivan, Leigh , McElnea, Angus , Ahern, Col , Smith, C. Douglas , Powell, Bernard , Hocking, Rosalie
- Date: 2010
- Type: Text , Journal article
- Relation: Environmental Science and Technology Vol. 44, no. 6 (2010), p. 1968-1973
- Full Text:
- Reviewed:
- Description: Tidal seawater inundation of coastal acid sulfate soils can generate Fe- and SO4-reducing conditions in previously oxicacidic sediments, This creates potential for mobilization of As during the redox transition. We explore the consequences for As by investigating the hydrology, porewater geochemistry, solid-phase speciation, and mineralogical partitioning of As across two tidal fringe toposequences. Seawater inundation induced a tidally controlled redox gradient. Maximum porewater As (∼400μg/L) occurred in the shallow (<1 m), intertidal, redox transition zone between Fe-oxidizing and SO 4-reducing conditions. Primary mechanisms of As mobilization include the reduction of solid-phase As(V) to As(III), reductive dissolution of As(V)-bearing secondary Fe(III) minerals and competitive anion desorption. Porewater As concentrations decreased in the zone of contemporary pyrite reformation, Oscillating hydraulic gradients caused by tidal pumping promote upward advection of As and Fe2+-enriched porewater in the intertidal zone, leading to accumulation of As(V)-enriched Fe(III) (hydr)oxides at the oxic sediment-water interface. While this provides a natural reactive-Fe barrier, it does not completely retard the flux of porewater As to overtopping surface waters. Furthermore, the accumulated Fe minerals may be prone to future reductive dissolution, A conceptual model describing As hydro-geochemical coupling across an intertidal fringe is presented. © 2010 American Chemical Society.
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