Skip Navigation


Occupational Medicine Advance Access originally published online on April 28, 2005
Occupational Medicine 2005 55(5):380-384; doi:10.1093/occmed/kqi087
This Article
Right arrow FREE Full Text (PDF) Freely available
Right arrow All Versions of this Article:
55/5/380    most recent
kqi087v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Search for citing articles in:
ISI Web of Science (2)
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by Lyons, J.
Right arrow Articles by Bilzon, J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Lyons, J.
Right arrow Articles by Bilzon, J.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

J. Lyons, Institute of Naval Medicine. © Crown Copyright 2005. Reproduced with the permission of the Controller of Her Majesty’s Stationery Office.

Influences of body composition upon the relative metabolic and cardiovascular demands of load-carriage

Jason Lyons, Adrian Allsopp and James Bilzon

Institute of Naval Medicine, Environmental Medicine Unit, Alverstoke Gosport, Hampshire PO12 2DL, UK

Aim To test the hypothesis that measures of aerobic fitness, body mass and indices of body composition will influence the metabolic and cardiovascular demands of simulated load-carriage tasks.

Method Twenty-eight healthy male volunteers, following assessment of maximal oxygen uptake and body composition, walked on a treadmill at 4 kph (1.11 m/s) for 60 min on gradients of 0, 3, 6 and 9% whilst carrying backpack loads of 0, 20 and 40 kg. During the final 3 min of each 5-min exercise bout, indirect respiratory calorimetry and heart rate data were collected and the ‘steady-state’ metabolic and cardiovascular (heart rate) demands quantified.

Results Absolute (ml/min) produced the strongest correlation (r=–0.64, P<0.01) with the metabolic demand of heavy load-carriage (40 kg). The body composition index lean body mass/(fat mass + external load) produced a moderate correlation (r=–0.52, P<0.01) with the metabolic demand of heavy load-carriage. The increases in metabolic and cardiovascular demands were greater when the load carried increased from 20 to 40 kg compared with 0 to 20 kg at all four gradients. A model incorporating anthropometric and physiological characteristics with gradient and load explains 89% of the variability in the metabolic demands of load-carriage compared with 82% using gradient and load alone.

Conclusion The results show that indices of body composition as well as absolute aerobic power influence the relative metabolic demands of load-carriage. Application of these measurements would ensure selection criteria for load-carriage occupations are based on lean muscle mass rather than running speed.

Keywords      Absolute ; body composition; cardiovascular demand; fitness tests; lean body mass/dead mass ratio; load-carriage; metabolic demand; occupational relevance

Correspondence to: Jason Lyons, Institute of Naval Medicine, Environmental Medicine Unit, Alverstoke, Gosport, Hampshire PO12 2DL, UK. Tel: +44 023 9276 8054; fax: +44-023-9250-4823; e-mail: lyonsj{at}inm.mod.uk


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer:
Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.