title: Blood lactate thresholds and walking/running economy are determinants of backpack-running performance in trained soldiers.
abstract: We developed a standardized laboratory treadmill protocol for assessing physiological responses to a simulated backpack load-carriage task in trained soldiers, and assessed the efficacy of blood lactate thresholds (LTs) and economy in predicting future backpack running success over an 8-mile course in field conditions. LTs and corresponding physiological responses were determined in 17 elite British soldiers who completed an incremental treadmill walk/run protocol to exhaustion carrying 20 kg backpack load. Treadmill velocity at the breakpoint (r = -0.85) and Δ 1 mmol l(-1) (r = -0.80) LTs, and relative V˙O2 at 4 mmol l(-1) (r = 0.76) and treadmill walk/run velocities of 6.4 (r = 0.76), 7.4 (r = 0.80), 11.4 (r = 0.66) and 12.4 (r = 0.65) km h(-1) were significantly associated with field test completion time. We report for the first time that LTs and backpack walk/run economy are major determinants of backpack load-carriage performance in trained soldiers.
authors.affiliation: Laboratory of Integrated Physiology, Department of Health and Human Performance, University of Houston, 3875 Holman Street, Houston, TX 77204, USA; Biomedicine and Sports Science Research Group, School of Life, Sport and Social Sciences, Edinburgh Napier University, Edinburgh EH11 4BN, Scotland, UK. Electronic address: rjsimpson@uh.edu.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Simpson
authors.affiliation: Biomedicine and Sports Science Research Group, School of Life, Sport and Social Sciences, Edinburgh Napier University, Edinburgh EH11 4BN, Scotland, UK.
authors.forename: Scott M
authors.initials: SM
authors.lastname: Graham
authors.affiliation: Neuromuscular Research Laboratory, Warrior Human Performance Center, University of Pittsburgh, Pittsburgh, PA 15213, USA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Connaboy
authors.affiliation: Biomedicine and Sports Science Research Group, School of Life, Sport and Social Sciences, Edinburgh Napier University, Edinburgh EH11 4BN, Scotland, UK.
authors.forename: Richard
authors.initials: R
authors.lastname: Clement
authors.affiliation: Department of Engineering Technology, University of Houston, 4734 Calhoun Road, Houston, TX 77004, USA.
authors.forename: Luca
authors.initials: L
authors.lastname: Pollonini
authors.affiliation: Biomedicine and Sports Science Research Group, School of Life, Sport and Social Sciences, Edinburgh Napier University, Edinburgh EH11 4BN, Scotland, UK.
authors.forename: Geraint D
authors.initials: GD
authors.lastname: Florida-James
mesh_terms: D000328:Adult; D015308:Anaerobic Threshold; D005080:Exercise Test; D006801:Humans; D019344:Lactic Acid / Q000097:blood*; D008297:Male; D008889:Military Personnel; D005082:Physical Exertion / Q000502:physiology; D012420:Running / Q000502:physiology*; D006113:United Kingdom; D016138:Walking / Q000502:physiology*; D016474:Weight-Bearing / Q000502:physiology*; D055815:Young Adult
chemical_list: D019344:Lactic Acid
keywords: Field test; Load-carriage; Occupational physiology; Special forces; Treadmill protocol; Ventilatory threshold