Live high: train low increases muscle buffer capacity and submaximal cycling efficiency
Gore, Christopher J and Hahn, Allan G and Aughey, Robert J and Martin, David T and Ashenden, M. J and Clark, Sally A and Garnham, Andrew P and Roberts, A. D and Slater, G. J and McKenna, Michael J (2001) Live high: train low increases muscle buffer capacity and submaximal cycling efficiency. Acta Physiological Scandinavica, 173 (3). pp. 275-286. ISSN 00016772Full text for this resource is not available from the Research Repository.
This study investigated whether hypoxic exposure increased muscle buffer capacity (βm) and mechanical efficiency during exercise in male athletes. A control (CON, n=7) and a live high:train low group (LHTL, n=6) trained at near sea level (600 m), with the LHTL group sleeping for 23 nights in simulated moderate altitude (3000 m). Whole body oxygen consumption (V˙O2) was measured under normoxia before, during and after 23 nights of sleeping in hypoxia, during cycle ergometry comprising 4×4-min submaximal stages, 2-min at 5.6 ± 0.4 W kg–1, and 2-min 'all-out' to determine total work and V˙O2peak. A vastus lateralis muscle biopsy was taken at rest and after a standardized 2-min 5.6 ± 0.4 W kg–1 bout, before and after LHTL, and analysed for βm and metabolites. After LHTL, βm was increased (18%, P < 0.05). Although work was maintained, V˙O2peak fell after LHTL (7%, P < 0.05). Submaximal V˙O2 was reduced (4.4%, P < 0.05) and efficiency improved (0.8%, P < 0.05) after LHTL probably because of a shift in fuel utilization. This is the first study to show that hypoxic exposure, per se, increases muscle buffer capacity. Further, reduced V˙O2 during normoxic exercise after LHTL suggests that improved exercise efficiency is a fundamental adaptation to LHTL.
|Uncontrolled Keywords:||altitude training, cycling effeciency, hypoxia, muscle buffering|
|Subjects:||RFCD Classification > 320000 Medical and Health Sciences
RFCD Classification > 220000 Social Sciences, Humanities and Arts-General
Faculty/School/Research Centre/Department > School of Sport and Exercise Science
|Depositing User:||Ms Phung T Tran|
|Date Deposited:||17 Jun 2007 14:13|
|Last Modified:||30 Mar 2015 03:14|
|ePrint Statistics:||View download statistics for this item|
|Citations in Scopus:||112 - View on Scopus|
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