title: The Unsuitability of Energy Expenditure Derived From Microtechnology for Assessing Internal Load in Collision-Based Activities.
abstract: This aim of this study was to examine the validity of energy expenditure derived from microtechnology when measured during a repeated-effort rugby protocol. Sixteen male rugby players completed a repeated-effort protocol comprising 3 sets of 6 collisions during which movement activity and energy expenditure (EEGPS) were measured using microtechnology. In addition, energy expenditure was estimated from open-circuit spirometry (EEVO2). While related (r = .63, 90%CI .08-.89), there was a systematic underestimation of energy expenditure during the protocol (-5.94 ± 0.67 kcal/min) for EEGPS(7.2 ± 1.0 kcal/min) compared with EEVO2(13.2 ± 2.3 kcal/min). High-speed-running distance (r = .50, 95%CI -.66 to .84) was related to EEVO2, while PlayerLoad was not (r = .37, 95%CI -.81 to .68). While metabolic power might provide a different measure of external load than other typically used microtechnology metrics (eg, high-speed running, PlayerLoad), it underestimates energy expenditure during intermittent team sports that involve collisions.
authors.forename: Jamie
authors.initials: J
authors.lastname: Highton
authors.forename: Thomas
authors.initials: T
authors.lastname: Mullen
authors.forename: Jonathan
authors.initials: J
authors.lastname: Norris
authors.forename: Chelsea
authors.initials: C
authors.lastname: Oxendale
authors.forename: Craig
authors.initials: C
authors.lastname: Twist
mesh_terms: D061725:Accelerometry; D004734:Energy Metabolism; D005538:Football / Q000502:physiology*; D040362:Geographic Information Systems; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D008297:Male; D010465:Perception; D064797:Physical Conditioning, Human; D005082:Physical Exertion / Q000502:physiology; D012420:Running / Q000502:physiology; D055815:Young Adult
chemical_list: D019344:Lactic Acid
keywords: GPS; accelerometry; rugby; tackle; training load