Revisiting Ventilatory and Cardiovascular Predictions of Whole-Body Metabolic Rate

Notley, Sean R.; Fullagar, Hugh; Lee, Daniel S.; Matsuda-Nakamura, Mayumi; Peoples, Gregory E; Taylor, Nigel A.S.

doi:10.1097/jom.0000000000000086

Cited by 14 publications

(5 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Following that reasoning, the energy cost of locomotion will be higher when loaded, and the markers of physiological strain will be higher, although the utility of cardiorespiratory variables as predictive metabolic surrogates is limited within occupational settings (Notley et al 2014a. Conversely, an unloaded individual can accomplish substantially more external work.…”

Section: Metabolic Costmentioning

confidence: 99%

Load carriage, human performance, and employment standards

Taylor

Peoples

Petersen

2016

Appl. Physiol. Nutr. Metab.

Self Cite

View full text Add to dashboard Cite

Abstract:The focus of this review is on the physiological considerations necessary for developing employment standards within occupations that have a heavy reliance on load carriage. Employees within military, fire fighting, law enforcement, and search and rescue occupations regularly work with heavy loads. For example, soldiers often carry loads >50 kg, whilst structural firefighters wear 20-25 kg of protective clothing and equipment, in addition to carrying external loads. It has long been known that heavy loads modify gait, mobility, metabolic rate, and efficiency, while concurrently elevating the risk of muscle fatigue and injury. In addition, load carriage often occurs within environmentally stressful conditions, with protective ensembles adding to the thermal burden of the workplace. Indeed, physiological strain relates not just to the mass and dimensions of carried objects, but to how those loads are positioned on and around the body. Yet heavy loads must be borne by men and women of varying body size, and with the expectation that operational capability will not be impinged. This presents a recruitment conundrum. How do employers identify capable and injury-resistant individuals while simultaneously avoiding discriminatory selection practices? In this communication, the relevant metabolic, cardiopulmonary, and thermoregulatory consequences of loaded work are reviewed, along with concomitant impediments to physical endurance and mobility. Also emphasised is the importance of including occupation-specific clothing, protective equipment, and loads during work-performance testing. Finally, recommendations are presented for how to address these issues when evaluating readiness for duty.Key words: backpacks, firefighter, load carriage, oxygen cost, military, employment standards, ventilation, work of breathing.Résumé : Cette analyse documentaire traite principalement des aspects physiologiques essentiels à l'élaboration de normes d'emploi pour des postes dont la fonction majeure est le transport de charges. Les employés dans l'armée, les pompiers, la police, les membres de recherche et sauvetage travaillent régulièrement avec de lourdes charges. Par exemple, les soldats transportent souvent des charges de >50 kg et les pompiers de bâtiments portent un vêtement de protection pesant de 20 à 25 kg et déplacent aussi des charges externes. On sait depuis longtemps que le port de charges lourdes modifie la démarche, la mobilité, le taux métabolique et le rendement tout en augmentant le risque de fatigue musculaire et de blessure. De plus, le déplacement des charges est effectué fréquemment dans des conditions environnementales stressantes et les vêtements de protection accroissent la charge thermique dans cet endroit. En outre, la contrainte physiologique ne dépend pas seulement de la masse et des dimensions des objets à déplacer, mais aussi de leur positionnement sur et autour du corps. Pourtant, il faut que ces charges soient déplacées par des hommes et des femmes de gabarit divers dont les capacités opérationnell...

show abstract

Section: Metabolic Costmentioning

confidence: 99%

Load carriage, human performance, and employment standards

Taylor

Peoples

Petersen

2016

Appl. Physiol. Nutr. Metab.

Self Cite

View full text Add to dashboard Cite

show abstract

“…21,22 These errors are associated with heat-and work-related increments in these surrogates that exceed changes in oxygen consumption. Therefore, oxygen consumption was measured directly using a portable, open-circuit, expired gas analysis and ventilation system (Metamax 3B, mass ¼ 1.82 kg; Cortex Biophysik, Leipzig, Germany).…”

Section: Physiological and Psychophysical Measurementsmentioning

confidence: 99%

Employment Standards for Australian Urban Firefighters

Taylor

Fullagar²,

Sampson³

et al. 2015

Journal of Occupational &Amp; Environmental Medicine

Self Cite

View full text Add to dashboard Cite

show abstract

“…It is well established that there is a proportional relationship between ventilation (

{\overset{V}{true}}_{normalE}

) and oxygen consumption (

\overset{\cdot}{normalV} {normalO}_{2}

) 8 – 24 . More precisely, the relationship is semilinear; it is linear during light to moderate exercise, but the gradient increases (

{\overset{V}{true}}_{normalE}

increases more than

\overset{\cdot}{normalV} {normalO}_{2}

) when the intensity of exercise is high 25 .…”

Section: Historical Overview: Estimation Of Energy Expenditure From Pmentioning

confidence: 99%

“…It is well established that there is a proportional relationship between ventilation ( )  V E and oxygen consumption ( ).  VO 2 [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24] More precisely, the relationship is semilinear; it is linear during light to moderate exercise, but the gradient increases (  V E increases more than  VO 2 ) when the intensity of exercise is high. 25 This relationship can be expressed by the equation…”

Section: The Relationship Between Ventilation and Oxygen Consumptionmentioning

confidence: 99%

A Review of the Evidence for the Use of Ventilation as a Surrogate Measure of Energy Expenditure

Gastinger

Donnelly

Dumond³

et al. 2014

J Parenter Enteral Nutr

View full text Add to dashboard Cite

Precise measurement of sedentary behavior and physical activity is necessary to characterize the dose-response relationship between these variables and health outcomes. The most frequently used methods employ portable devices to measure mechanical or physiological parameters (eg, pedometers, heart rate monitors, accelerometers). There is considerable variability in the accuracy of total energy expenditure (TEE) estimates from these devices. This review examines the potential of measurement of ventilation (VE) to provide an estimate of free-living TEE. The existence of a linear relationship between VE and energy expenditure (EE) was demonstrated in the mid-20th century. However, few studies have investigated this parameter as an estimate of EE due to the cumbersome equipment required to measure VE. Portable systems that measure VE without the use of a mouthpiece have existed for about 20 years (respiratory inductive plethysmography). However, these devices are adapted for clinical monitoring and are too cumbersome to be used in conditions of daily life. Technological innovations of recent years (small electromagnetic coils glued on the chest/back) suggest that VE could be estimated from variations in rib cage and abdominal distances. This method of TEE estimation is based on the development of individual/group calibration curves to predict the relationship between ventilation and oxygen consumption. The new method provides a reasonably accurate estimate of TEE in different free-living conditions such as sitting, standing, and walking. Further work is required to integrate these electromagnetic coils into a jacket or T-shirt to create a wearable device suitable for long-term use in free-living conditions.

show abstract

Revisiting Ventilatory and Cardiovascular Predictions of Whole-Body Metabolic Rate

Abstract: Ventilatory predictions were more precise, but errors from heart-rate predictions could be minimized by using thermal-state and exercise mode-specific predictions.

Cited by 14 publications

References 35 publications

Load carriage, human performance, and employment standards

Load carriage, human performance, and employment standards

Employment Standards for Australian Urban Firefighters

A Review of the Evidence for the Use of Ventilation as a Surrogate Measure of Energy Expenditure

Contact Info

Product

Resources

About