The Reliability of the Extra Load Index as a Measure of Relative Load Carriage Economy

Sean Hudson, Carlton Cooke, Ray Lloyd

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The aim of this study was to measure the reliability of the extra load index (ELI) as a method for assessing relative load carriage economy. Seventeen volunteers (12 males, 5 females) performed walking trials at 3 km·h−1, 6 km·h−1 and a self-selected speed. Trial conditions were repeated 7 days later to assess test–retest reliability. Trials involved four 4-minute periods of walking, each separated by 5 min of rest. The initial stage was performed unloaded followed in a randomised order by a second unloaded period and walking with backpacks of 7 and 20 kg. Results show ELI values did not differ significantly between trials for any of the speeds (p = 0.46) with either of the additional loads (p = 0.297). The systematic bias, limits of agreement and coefficients of variation were small in all trial conditions. We conclude the ELI appears to be a reliable measure of relative load carriage economy. Practitioner Summary: This paper demonstrates that the ELI is a reliable measure of load carriage economy at a range of walking speeds with both a light and heavy load. The ELI, therefore, represents a useful tool for comparing the relative economy associated with different load carriage systems.

LanguageEnglish
Pages1250-1254
Number of pages5
JournalErgonomics
Volume60
Issue number9
Early online date1 Feb 2017
DOIs
Publication statusPublished - 2 Sep 2017

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Walking
economy
Reproducibility of Results
Volunteers
Light
trend
Values
Walking Speed

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Hudson, Sean ; Cooke, Carlton ; Lloyd, Ray. / The Reliability of the Extra Load Index as a Measure of Relative Load Carriage Economy. In: Ergonomics. 2017 ; Vol. 60, No. 9. pp. 1250-1254.
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The Reliability of the Extra Load Index as a Measure of Relative Load Carriage Economy. / Hudson, Sean; Cooke, Carlton; Lloyd, Ray.

In: Ergonomics, Vol. 60, No. 9, 02.09.2017, p. 1250-1254.

Research output: Contribution to journalArticle

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