Loading...
Muscle glycogen utilization during an Australian Rules Football game
Routledge, Harry E. Leckey, Jill J. Lee, Matt J. Garnham, Andrew Graham, Stuart Burgess, Darren Burke, Louise M. Erskine, Robert M. Close, Graeme L. Morton, James P.
Routledge, Harry E.
Leckey, Jill J.
Lee, Matt J.
Garnham, Andrew
Graham, Stuart
Burgess, Darren
Burke, Louise M.
Erskine, Robert M.
Close, Graeme L.
Morton, James P.
Abstract
Purpose: To better understand the carbohydrate (CHO) requirement of Australian Football (AF) match play by quantifying muscle glycogen utilization during an in-season AF match. Methods: After a 24-h CHO-loading protocol of 8 and 2 g/kg in the prematch meal, 2 elite male forward players had biopsies sampled from m. vastus lateralis before and after participation in a South Australian Football League game. Player A (87.2 kg) consumed water only during match play, whereas player B (87.6 kg) consumed 88 g CHO via CHO gels. External load was quantified using global positioning system technology. Results: Player A completed more minutes on the ground (115 vs 98 min) and covered greater total distance (12.2 vs 11.2 km) than player B, although with similar high-speed running (837 vs 1070 m) and sprinting (135 vs 138 m). Muscle glycogen decreased by 66% in player A (pre: 656 mmol/kg dry weight [dw], post: 223 mmol/kg dw) and 24% in player B (pre: 544 mmol/kg dw, post: 416 mmol/kg dw). Conclusion: Prematch CHO loading elevated muscle glycogen concentrations (ie, >500 mmol/kg dw), the magnitude of which appears sufficient to meet the metabolic demands of elite AF match play. The glycogen cost of AF match play may be greater than in soccer and rugby, and CHO feeding may also spare muscle glycogen use. Further studies using larger sample sizes are now required to quantify the interindividual variability of glycogen cost of match play (including muscle and fiber-type-specific responses), as well examining potential metabolic and ergogenic effects of CHO feeding.
Keywords
carbohydrate loading, vastus lateralis, AF, high-speed running
Date
2019
Type
Journal article
Journal
International Journal of Sports Physiology and Performance
Book
Volume
14
Issue
1
Page Range
122-124
Article Number
ACU Department
Centre for Exercise and Nutrition
Faculty of Health Sciences
Faculty of Health Sciences
Collections
Relation URI
Source URL
Event URL
Open Access Status
Published as green open access
License
File Access
Controlled
Open
Open