Brianna Larsen

Dr. Brianna Larsen


Research Focus & Metrics

Academic Career Length

15Years (2012-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
1 October 2015 in Journal of Thermal Biology
Verified
Journal Article
Closed access
BLBrianna Larsen
Brianna Larsen
RSRodney Snow
Rodney Snow
Brad AisbettBrad Aisbett
Brad Aisbett

17 September 2015 in PLOS ONE
Verified
Journal Article
Open access
PDF file
BLBrianna Larsen
Brianna Larsen
RSRod Snow
Rod Snow
Grace VincentGrace Vincent
Grace Vincent
JTJacqueline Tran
Jacqueline Tran
AWAlexander Wolkow
Alexander Wolkow
Brad AisbettBrad Aisbett
Brad Aisbett
This study assessed the accumulated effect of ambient heat on the performance of, and physiological and perceptual responses to, intermittent, simulated wildfire fighting tasks over three consecutive days. Firefighters (n = 36) were matched and allocated to either the CON (19°C) or HOT (33°C) condition. They performed three days of intermittent, self-paced simulated firefighting work, interspersed with physiological testing. Task repetitions were counted (and converted to distance or area) to determine work performance. Participants were asked to rate their perceived exertion and thermal sensation after each task. Heart rate, core temperature (Tc), and skin temperature (Tsk) were recorded continuously throughout the simulation. Fluids were consumed ad libitum. Urine volume was measured throughout, and urine specific gravity (USG) analysed, to estimate hydration. All food and fluid consumption was recorded. There was no difference in work output between experimental conditions. However, significant variation in performance responses between individuals was observed. All measures of thermal stress were elevated in the HOT, with core and skin temperature reaching, on average, 0.24 ± 0.08°C and 2.81 ± 0.20°C higher than the CON group. Participants’ doubled their fluid intake in the HOT condition, and this was reflected in the USG scores, where the HOT participants reported significantly lower values. Heart rate was comparable between conditions at nearly all time points, however the peak heart rate reached each circuit was 7 ± 3% higher in the CON trial. Likewise, RPE was slightly elevated in the CON trial for the majority of tasks. Participants’ work output was comparable between the CON and HOT conditions, however the performance change over time varied significantly between individuals. It is likely that the increased fluid replacement in the heat, in concert with frequent rest breaks and task rotation, assisted with the regulation of physiological responses (e.g., heart rate, core temperature).

9 November 2015 in Frontiers in Physiology
Verified
Journal Article
Open access
BLBrianna Larsen
Brianna Larsen
RSRod Snow
Rod Snow
MWMichael Williams-Bell
Michael Williams-Bell
Brad AisbettBrad Aisbett
Brad Aisbett
Purpose: To assess the impact of very hot (45°C) conditions on the performance of, and physiological responses to, a simulated firefighting manual-handling task compared to the same work in a temperate environment (18°C). Methods: 10 male volunteer firefighters performed a 3-hour protocol in both 18°C (CON) and 45°C (VH). Participants intermittently performed 12 × 1-minute bouts of raking, 6 × 8-minute bouts of low-intensity stepping, and 6 × 20-minute rest periods. The area cleared during the raking task determined work performance. Core temperature, skin temperature, and heart rate were measured continuously. Participants also periodically rated their perceived exertion (RPE) and thermal sensation. Firefighters consumed water ad libitum. Urine specific gravity and changes in body mass determined hydration status. Results: Firefighters raked 19% less debris during the VH condition. Core and skin temperature were 0.99 ± 0.20°C and 5.45 ± 0.53°C higher, respectively, during the VH trial, and heart rate was 14-36 beats.min-1 higher in the VH trial. Firefighters consumed 2950 ± 1034 mL of water in the VH condition, compared to 1290 ± 525 in the CON trial. Sweat losses were higher in the VH (1886 ± 474 mL) compared to the CON trial (462 ± 392 mL), though both groups were hydrated upon protocol completion (USG < 1.020). Participants’ average RPE was higher in the VH (15.6 ± 0.9) compared to the CON trial (12.6 ± 0.9). Similarly, the firefighers' thermal sensation scores were significantly higher in the VH (6.4 ± 0.5) compared to the CON trial (4.4 ± 0.4). Conclusions: Despite the decreased work output and aggressive fluid replacement observed in the VH trial, firefighters’ experienced increases in thermal stress and exertion. Fire agencies should prioritise the health and safety of fire personnel in very hot temperatures, and consider the impact of reduced productivity on fire suppression efforts.

BLBrianna Larsen
Brianna Larsen
Brad AisbettBrad Aisbett
Brad Aisbett
ASAaron Silk
Aaron Silk
This study investigated the injuries sustained by an Australian specialist police division. Injury records spanning four-years were analyzed. The role being performed when the injury occurred, injury cause, body part injured, and injury-related costs were quantified. The percentage of personnel injured multiple times was documented. One hundred and thirty eight personnel reported injuries, 58 of these on multiple occasions. This resulted in 229 injuries and 76 claims being raised. Half of the injuries occurred during operational policing tasks, however training activities accounted for >30% of injuries. The most common injury was strain/sprain, and upper body injuries were 2.5-times more common than lower-body or torso injuries. 1107 shifts were lost, and injuries cost the organization $487,159 (Australian Dollars) over the four-year period. The injury costs (both financial and in manpower) may prompt policy makers to review the current training and post-injury rehabilitation protocols.

17 July 2012 in Ergonomics
Verified
Journal Article
Closed access
BLBrianna Larsen
Brianna Larsen
Brad AisbettBrad Aisbett
Brad Aisbett
Workers in physically demanding occupations (PDOs) are frequently subjected to physical selection tests. To avoid legal ramifications, workplaces must be able to show that any personnel selection procedures reflect the inherent requirements of the job. A job task analysis (JTA) is fundamental in determining the work tasks required for employees. To date, there are no published instructions guiding PDO researchers on how to conduct job task analyses. Job task analysis research for non-PDOs offers some insight into the expected reliability and validity of data obtained on the most prevalent task domains in job analysis (importance, frequency, time spent and difficulty). This review critiques such research, and the existing published material on JTA of PDOs, and provides recommendations for future research and practice. Practitioner Summary: There are no published guidelines for physically demanding occupation (PDO) researchers conducting job task analysis (JTA). Given the legal consequences of improperly conducted JTA, scientifically valid instructions for JTA practitioners are required. This review critiques existing research which analyses reliabilities of JTA data, and provides guidelines for PDO researchers conducting JTA.

1 April 2014
Verified
Journal Article
Closed access
BLBrianna Larsen
Brianna Larsen
KNKevin Netto
Kevin Netto
Brad AisbettBrad Aisbett
Brad Aisbett
Eleven recreationally active males performed 11 circuits of military work, wearing torso armor on one occasion, and full armor on another. Performance was measured by the time taken to complete individual tasks, and the overall time to completion (TTC) for each circuit. Heart rate, intestinal temperature, ratings of perceived exertion (RPE), and thermal sensation were recorded after each circuit. Participants\u27 circuit TTC was no different between conditions; however, specific tasks were differentially impeded by the two armor configurations. Vaulting and crawling were significantly slower (0.28 ± 0.06 and 0.55 ± 0.26 seconds) in full armor; however, box lifting and shooting were significantly slower (0.36 ± 0.18 and 0.86 ± 0.23 seconds) when wearing torso armor. Heart rate and core temperature were significantly higher during the full armor trial (5 ± 1 beats · min(-1) and 0.22 ± 0.03 °C). Similarly, RPE and thermal sensation were significantly higher (1 ± 0 and 0.5 ± 0.0) during the full armor condition. Military tasks were differentially impaired by the armor configurations used, which suggests a need to explore role-specific armor for military personnel. Physiological and perceptual responses were elevated in full armor, which could be exacerbated during longer periods of work or in hot conditions