Association of firefighting exposures with lung function using a novel job exposure matrix (JEM).

OBJECTIVES: Characterisation of firefighters' exposures to dangerous chemicals in smoke from non-wildfire incidents, directly through personal monitoring and indirectly from work-related records, is scarce. The aim of this study was to evaluate the association between smoke particle exposures (P) and pulmonary function. METHODS: The study period spanned from January 2010 through September 2021. Routine firefighting P were estimated using fire incident characteristics, response data and emission factors from a novel job exposure matrix. Linear mixed effects modelling was employed to estimate changes in pulmonary function as measured by forced expiratory volume in one second (FEV1). Models controlled for age, race/ethnicity, height, smoking and weight. RESULTS: Every 1000 kg P was associated with 13 mL lower FEV1 (ß=-13.34; 95% CI=-13.98 to -12.70) over the entire 12-year follow-up period. When analysing exposures within 3 months before PFT measurements, 1000 kg P was associated with 27 mL lower FEV1 (ß=-26.87; 95% CI=-34.54 to -19.20). When evaluating P estimated within 3 months of a pulmonary function test (PFT), stronger associations were observed among those most highly exposed to the World Trade Center (WTC) disaster (ß=-12.90; 95% CI=-22.70 to -2.89); the association of cumulative exposures was similar for both highly and less highly exposed individuals. DISCUSSION: Smoke particle exposures were observed to have modest short-term and long-term associations with pulmonary function, particularly in those who, previously, had high levels of WTC exposure. Future work examining the association between P and pulmonary function among non-WTC exposed firefighters will be essential for disentangling the effects of ageing, routine firefighting and WTC exposures.

Evaluation of the relationship between occupational-specific task performance and measures of physical fitness, cardiovascular and musculoskeletal health in firefighters.

INTRODUCTION: Firefighters are required to perform physically strenuous tasks such as hose drags, victim rescues, forcible entries and stair climbs to complete their public safety mission. Occupational-specific tasks are often used to evaluate the ability of firefighters to adequately/safely perform their duties. Depending on the regions, occupational-specific tasks include six to eight individual tasks, which emphasize distinct aspects of their physical fitness, while also requiring different levels of cardiovascular (CVH) and musculoskeletal health (MSH). Therefore, the aim of this study was to evaluate the relationship between specific occupational task performance and measures of physical fitness, cardiovascular and musculoskeletal health. METHODS: Using a cross-sectional design, 282 full-time male and female firefighters were recruited. A researcher-generated questionnaire and physical measures were used to collect data on sociodemographic characteristics, CVH, MSH and weekly physical activity habits. Physical measures were used to collect data on physical fitness and occupational-specific task performance. RESULTS: Absolute cardiorespiratory fitness (abV̇O2max), grip strength, leg strength, push-ups, sit-ups and lean body mass (all p < 0.001) had an inverse association with completion times on all occupational-specific tasks. Age was positively related to the performance of all tasks (all p < 0.05). Higher heart rate variability (HRV) was associated with better performance on all tasks (all p < 0.05). Bodyfat percentage (BF%) and diastolic blood pressure were positively associated with the step-up task (p < 0.05). Lower back musculoskeletal injury (LoBMSI), musculoskeletal discomfort (MSD), and lower limb MSD were associated with a decreased odds of passing the step-up. Upper body MSIs (UBMSI), LoBMSIs and Lower back MSD were associated with decreased odds of passing the rescue drag. CONCLUSION: Firefighters that were taller, leaner, stronger and fitter with a more favourable CVH profile, higher HRV and less musculoskeletal discomfort performed best on all occupational-specific tasks.

Admiration and motivation: key factors in managing PTSD among firefighters.

Post-traumatic stress disorder (PTSD) presents a significant challenge for firefighters. While research suggests that admiration may have a positive impact on individual psychological well-being, its specific influence on PTSD among firefighters remains unexplored. This study aims to investigate the association between admiration, motivation (both internal and external), and PTSD in a sample of 2156 firefighters in order to identify effective coping strategies for managing PTSD in this population. The findings indicate a statistically significant inverse relationship between admiration and PTSD, with motivation acting as a mediator. Furthermore, it is noteworthy that internal motivation is negatively correlated with PTSD in the model, while external motivation shows a positive correlation. The results suggest that feelings of admiration are associated with firefighter PTSD via motivation. Specifically, internal motivation stemming from admiration appears to have a mitigating effect on PTSD symptoms, while external motivation is linked to exacerbation of these symptoms. These results have implications for the development of theoretical frameworks and practical interventions aimed at preventing PTSD among firefighters.

Maintaining the working state of firefighters by utilizing self-concept clarity as a resource.

The working state of firefighters is important for their own safety as well as that of the general public. The purpose of this study is to investigate the correlations between self-concept clarity, resilience, work engagement, and job burnout among firefighters, as well as the impacts of self-concept clarity and resilience as resources that can maintain their working state. Based on data from 2,156 firefighters, analysis showed that self-concept clarity was negatively associated with job burnout and positively associated with work engagement. The results also showed that self-concept clarity had a direct effect on job burnout and work engagement, and an indirect effect by improving the firefighters' resilience. Maintaining and improving their self-concept clarity and resilience promises to be an effective strategy for guaranteeing the working state of firefighters.

Relationships between job stress, post-traumatic stress and musculoskeletal symptoms in firefighters and the role of job burnout and depression mediators: a bayesian network model.

INTRODUCTION: Job stress, post-traumatic stress disorder (PTSD), and negative psychological outcomes in firefighters can be caused, or aggravated, by their work. These mental disorders can impart musculoskeletal symptoms. This study aimed to investigate relationships between musculoskeletal and psychological disorders in a population of firefighters using a Bayesian network model. METHODS: This cross-sectional study, conducted in 2022, included 2339 firefighters who completed questionnaires during their rest periods. The questionnaires comprised of demographical information, the Occupational Stress Questionnaire-HSE, the PTSD Checklist, Maslach Burnout Inventory, Center for Epidemiologic Studies - Depression scale (CES-D), and Nordic Musculoskeletal Questionnaire. GeNIe academic software was used to analyze the Bayesian network. RESULTS: High job stress and high PTSD each increased the probability of musculoskeletal symptoms by 34%. When combined, high job stress and high PTSD increased the probability of musculoskeletal symptoms by 37%. Among the mediator's burnout and depression, depression had the highest association with musculoskeletal symptoms. CONCLUSIONS: Job stress and PTSD can increase musculoskeletal symptoms and are influenced by psychological mediators (like burnout and depression). Adopting preventive and therapeutic measures to mitigate job stress and PTSD, mitigate and rehabilitate WMSD, and manage associated mediators are critical for the mental and physical health of firefighters.

Exposure to benzotriazoles and benzothiazoles in Czech male population and its associations with biomarkers of liver function, serum lipids and oxidative stress.

INTRODUCTION: Benzotriazoles and benzothiazoles (BTs) are high-production volume chemicals as well as widely distributed emerging pollutants with potential health risk. However, information about human exposure to BTs and associated health outcomes is limited. OBJECTIVE: We aimed to characterise exposure to BTs among Czech men, including possible occupational exposure among firefighters, its predictors, and its associations with liver function, serum lipids and oxidative stress. METHODS: 165 participants (including 110 firefighters) provided urine and blood samples that were used to quantify the urinary levels of 8 BTs (high-performance liquid chromatography-tandem mass spectrometry), and 4 liver enzymes, cholesterol, low-density lipoprotein, and 8-hydroxy-2'-deoxyguanosine. Linear regression was used to assess associations with population characteristics and biomarkers of liver function, serum lipids and oxidative stress. Regression models were adjusted for potential confounding variables and false discovery rate procedure was applied to account for multiplicity. RESULTS: The BTs ranged from undetected up to 46.8 ng/mL. 2-hydroxy-benzothiazole was the most predominant compound (detection frequency 83%; median 1.95 ng/mL). 1-methyl-benzotriazole (1M-BTR) was measured in human samples for the first time, with a detection frequency 77% and median 1.75 ng/mL. Professional firefighters had lower urinary 1M-BTR compared to non-firefighters. Urinary 1M-BTR was associated with levels of γ-glutamyl transferase (ß = - 17.54%; 95% CI: - 26.127, - 7.962). CONCLUSION: This is the first study to investigate BT exposure in Central Europe, including potentially exposed firefighters. The findings showed a high prevalence of BTs in the study population, the relevance of 1M-BTR as a new biomarker of exposure, and an urgent need for further research into associated adverse health outcomes.

Recalled protective childhood experiences are associated with positive emotional expression in active-duty firefighters.

There is a wealth of research linking adverse childhood experiences (ACEs) with negative outcomes later in life, but less research has focused on the effects of protective childhood experiences (PCEs). PCEs have been shown broadly to promote resilience, but the precise nature of this association is not clear, particularly in studies of at-risk adults. The current investigation explored the association between recollection of early life experiences and in vivo emotional responses in at-risk adults. In 2018, 56 active-duty firefighters reported childhood experiences via a questionnaire. Using a semistructured interview, firefighters then responded to questions about recent emotionally evocative experiences (positive and negative) as a firefighter. Emotion was measured in vivo via sympathetic arousal and recorded facial expressions of emotion. Individuals who reported more PCEs expressed significantly more facial expressions of positive emotion across contexts, sr2 = .11-.14. Early childhood experiences were not significantly associated with negative facial expressions or changes in sympathetic reactivity, but ACEs were associated with tonic levels of arousal in a negative context, r = -.36. Given the adaptive role of positive emotions in adjustment to adverse events, the current investigation suggests a potential protective association between PCEs and the expression of emotion even within a high-risk context, which could help explain the resilience promoting role of PCEs.

Exploring the association between post-critical incident intervention preferences and self-reported coping self-efficacy among firefighters.

Critical incident stress debriefing (CISD) is a commonly utilized intervention in the fire service that aims to minimize psychological harm and adverse mental health outcomes after a potentially traumatic incident. This study aimed to explore firefighter preferences regarding CISD and alternative post-critical incident interventions in relation to firefighter coping self-efficacy (FFCSE) and trauma coping self-efficacy (CSE-T). Firefighters (N = 241) completed an online survey and provided complete data. Most participants were White (n = 203, 84.2%), non-Hispanic (n = 221, 91.7%) men (94.2%; n = 227). CISD was the most preferred intervention among firefighters (n = 113, 46.9%) as compared to informal peer support (n = 31, 12.9%), formal one-on-one counseling (n = 29, 12.0%), and no intervention (n = 68, 28.2%). Firefighters who preferred CISD had statistically significant lower levels of FFCSE, R2 = .033-.044, ps = .012-.030, and CSE-T, R2 = .035-.061 ps = .017-.024, compared to those who preferred no intervention. Firefighters who preferred formal one-on-one counseling had statistically significantly lower levels of FFCSE, R2 = .033-.044, ps = .003-.011, and CSE-T, R2 = .035-0.061, p < .001-p = .002, compared to those who preferred no intervention. The findings from this study may guide future research to increase knowledge on firefighter intervention preferences and the association between preference and coping self-efficacy.

Prevalence and predictors of colon and prostate cancer screening among volunteer firefighters: The United States Firefighter Cancer Assessment and Prevention Study.

BACKGROUND: Although firefighters have increased risk for colon and prostate cancer, limited information exists on screening practices for these cancers in volunteer firefighters who compose two-thirds of the US fire service. We estimated the prevalence of colon and prostate cancer screening among volunteer firefighters using eligibility criteria from 4 evidence-based screening recommendations and evaluated factors influencing screening. METHODS: We evaluated colon (n = 569) and prostate (n = 498) cancer screening prevalence in a sample of US volunteer firefighters using eligibility criteria from the US Preventive Services Taskforce (USPSTF), National Fire Protection Association, American Cancer Society, and National Comprehensive Cancer Network. We assessed associations with fire service experience, demographics, and cancer risk perception based on USPSTF guidelines. RESULTS: For those eligible based on USPSTF guidelines, colon and prostate cancer screening prevalence was 51.7% (95% CI: 45.7, 57.8) and 48.8% (95% CI: 40.0, 57.6), respectively. Higher odds of colon and prostate cancer screening were observed with older age and with some college education compared to those with less education. Fire service experience and cancer risk perception were not associated with screening practices. CONCLUSION: This is the first large study to assess colon and prostate cancer screening among US volunteer firefighters based on different screening guidelines. Our findings suggest gaps in cancer prevention efforts in the US volunteer fire service. Promoting cancer screening education and opportunities for volunteer firefighters by their fire departments, healthcare professionals, and public health practitioners, may help to address the gaps.

Characterization of fire investigators' polyaromatic hydrocarbon exposures using silicone wristbands.

BACKGROUND: Exposures to polyaromatic hydrocarbons (PAHs) contribute to cancer in the fire service. Fire investigators are involved in evaluations of post-fire scenes. In the US, it is estimated that there are up to 9000 fire investigators, compared to approximately 1.1 million total firefighting personnel. This exploratory study contributes initial evidence of PAH exposures sustained by this understudied group using worn silicone passive samplers. OBJECTIVES: Evaluate PAH exposures sustained by fire investigators at post-fire scenes using worn silicone passive samplers. Assess explanatory factors and health risks of PAH exposure at post-fire scenes. METHODS: As part of a cross-sectional study design, silicone wristbands were distributed to 16 North Carolina fire investigators, including eight public, seven private, and one public and private. Wristbands were worn during 46 post-fire scene investigations. Fire investigators completed pre- and post-surveys providing sociodemographic, occupational, and post-fire scene characteristics. Solvent extracts from wristbands were analyzed via gas chromatography-mass spectrometry (GC-MS). Results were used to estimate vapor-phase PAH concentration in the air at post-fire scenes. RESULTS: Fire investigations lasted an average of 148 minutes, standard deviation ± 93 minutes. A significant positive correlation (r=0.455, p<.001) was found between investigation duration and PAH concentrations on wristbands. Significantly greater time-normalized PAH exposures (p=0.039) were observed for investigations of newer post-fire scenes compared to older post-fire scenes. Regulatory airborne PAH exposure limits were exceeded in six investigations, based on exposure to estimated vapor-phase PAH concentrations in the air at post-fire scenes. DISCUSSION: Higher levels of off-gassing and suspended particulates at younger post-fire scenes may explain greater PAH exposure. Weaker correlations are found between wristband PAH concentration and investigation duration at older post-fire scenes, suggesting reduction of off-gassing PAHs over time. Exceedances of regulatory PAH limits indicate a need for protection against vapor-phase contaminants, especially at more recent post-fire scenes.

Exposure to aggression in three contexts of emergency response: A longitudinal examination of the relationship with psychological characteristics of the emergency responder.

Some emergency responders are more often exposed to workplace aggression than others. Victimological theories and previous studies suggest that characteristics of the target may predict exposure to workplace aggression. This paper examines the relationship between negative affect, hostile attribution, dominance, empathy, self-evaluations, and exposure to workplace aggression among emergency responders. Emergency medical workers, firefighters and police officers in the Netherlands filled in a survey during three measurement occasions (6 months apart). Results from the three occupational groups were presented separately. Results suggest that some psychological characteristics are related to exposure to workplace aggression, but that the contribution of these characteristics in the explanation of exposure to workplace aggression is limited. In addition, although differences between occupational groups could not be statistically tested due to differences in the factor structure of exposure to workplace aggression between the three groups of emergency response, differences seem to occur in models between emergency response contexts. Implications and suggestions for future research are discussed.

Validity of submaximal aerobic capacity and strength tests in firefighters.

BACKGROUND: Typically, the fitness of UK firefighters is assessed via submaximal estimate methods due to the low demands on time, money, expertise and equipment. However, the firefighter-specific validity of such testing in relation to maximum aerobic capacity (V˙O2max) and particularly muscular strength is not well established. AIMS: To examine the validity of submaximal methods to estimate V˙O2max and maximal strength in operational firefighters. METHODS: Twenty-two full-time operational firefighters (3 female) completed same-day submaximal (Chester Step Test; CST) and maximal (treadmill) assessments of V˙O2max, with a sub-sample of 10 firefighters (1 female) also completing submaximal and maximal back-squat (i.e. one repetition maximum; 1RM) assessments. All participants then completed the Firefighter Simulation Test (FFST) within 2-4 days. RESULTS: CST underestimated actual V˙O2max by 1.4 ml·kg-1·min-1 (~3%), although V˙O2max values were positively correlated (r = 0.61, P < 0.01) and not significantly different. Estimated V˙O2max values negatively correlated with FFST performance (r = -0.42). Predicted 1RM underestimated actual 1RM by ~2%, although these values were significantly correlated (r = 0.99, P < 0.001) and did not significantly differ. The strongest predictive model of FFST performance included age, body mass index, and direct maximal measures of 1RM and V˙O2max. CONCLUSIONS: Submaximal back-squat testing offers good validity in estimating maximum firefighter strength without exposure to the fatigue associated with maximal methods. The CST provides a reasonably valid and cost-effective V˙O2max estimate which translates to firefighting task performance, although the error observed means it should be used cautiously when making operational decisions related to V˙O2max benchmarks.

A comparison between the effects of simulation of basic CPR training and workshops on firefighters' knowledge and skills: experimental study.

BACKGROUND: One of the most common causes of death worldwide is cardiopulmonary arrest. Firefighters are among the first responders at the scenes of accidents and can, therefore, play a key part in performing basic cardiopulmonary resuscitation (CPR) for victims who need it. The present study was conducted to compare the effects of simulation training against workshops on the CPR knowledge and skills of firefighters in the south of Iran. METHODS: This experimental (Interventional) study was conducted on 60 firefighters of south of Fars province, Iran. The study was undertaken from March to July 2023. Through random allocation, the participants were divided into two groups: simulation-based training (30 members) and traditional workshop training (30 members). The participants' CPR knowledge and practical skills were measured before, immediately after, and three months after intervention. RESULTS: The findings of the study revealed a statistically significant difference between the pretest and posttest CPR knowledge and skill mean scores of the simulation groups as compared to the workshop group (p < 0.001). As measured three months after the intervention, the firefighters' knowledge and skill mean scores were still significantly different from their pretest mean scores (p < 0.001); however, they had declined, which can be attributed to the fact that the study population did not frequently exercise CPR. CONCLUSION: Based on the findings of the study, even though both methods of education were effective on enhancing the firefighters' CPR knowledge and skill, simulation training had a far greater impact than training in workshops. In view of the decline in the participants' knowledge and skill scores over time, it is recommended that short simulation training courses on CPR should be repeated on a regular basis.

Clinical and psychological implications of post-traumatic stress in firefighters: a moderated network study.

Firefighters are frequently exposed to trauma and may experience a unique symptom presentation of post-traumatic stress. Prior research has identified stronger associations between certain post-traumatic stress symptoms (e.g. detachment, intrusions, physiological reactivity) using network analysis. However, little is known about the effects of symptom severity and emergency work-related trauma on symptom networks. The present study probed the network structure of post-traumatic stress symptoms in trauma-exposed firefighters (N = 871) to model the dynamic interactions of psychological symptoms. We developed a network of post-traumatic stress symptoms and a network of post-traumatic stress with clinical covariates and used moderated network modelling to assess the effects of having PTSD and experiencing work-related trauma on the networks. We identified high edge correlations between several nodes (e.g. startle/hypervigilance, internal/external cue avoidance, detachment/lack of interest) and high centrality of detachment, external cue avoidance, and flashbacks. Additionally, having PTSD moderated positive network associations between risk-taking and suicidality and between distorted blame and post-traumatic cognitions. Work-related trauma moderated negative associations between appetite gain and loss and appetite loss and suicidality. Findings suggest that targeting specific symptoms of detachment, external cue avoidance, and flashbacks could allow for the development of effective trauma-informed interventions for these populations.

Integrated Portable and Stationary Health Impact-Monitoring System for Firefighters.

The multi-layered negative effects caused by pollutants released into the atmosphere as a result of fires served as the stimulus for the development of a system that protects the health of firefighters operating in the affected area. A collaborative network comprising mobile and stationary Internet of Things (IoT) devices that are furnished with gas sensors, along with a remote server, constructs a resilient framework that monitors the concentrations of harmful emissions, characterizes the ambient air quality of the vicinity where the fire transpires, adopting European Air Quality levels, and communicates the outcomes via suitable applications (RESTful APIs and visualizations) to the stakeholders responsible for fire management decision making. Different experimental evaluations adopting separate contexts illustrate the operation of the infrastructure.

A single rapid heat stress episode does not result in prolonged elevations in salivary cortisol and C-reactive protein production in firefighters.

In the present experiment, we evaluated the impact of rapid heat stress (RHS) on salivary cortisol and C-reactive protein production pre-RHS, post-RHS, and 24 and 48 h post-RHS exposure among firefighters. Previous research has demonstrated that RHS increases salivary cortisol during RHS and immediately post-RHS exposure. However, no research has evaluated the duration necessary to return to baseline cortisol levels following RHS. Additionally, no studies have analyzed the impact of RHS on inflammatory biomarkers, such as C-reactive protein. This study hypothesized that salivary cortisol and C-reactive protein levels would increase following RHS and then return to pre-RHS levels within 24 h post-exposure. Twenty-four participants performed a steady-state treadmill protocol in an environmental chamber (35 °C; 45% humidity) in full firefighter personal protective equipment until reaching either a core temperature (Tc) of 39 °C or a volitional maximum. The subjects had their saliva collected via the passive drool protocol pre-RHS, post-RHS, and 24 and 48 h post-RHS. Pre-RHS of 0.23 ± 0.03 µg/dL increased post-RHS to 0.51 ± 0.06 µg/dL (p < 0.001). This finding supports previous literature demonstrating the immediate impact of RHS. There were no changes in C-reactive protein. The novel finding of this study is that salivary cortisol levels return to baseline in the 24 h post-RHS exposure. This indicates that 24 h is recommended to recover from RHS and should be applied to prevent the chronic stress response.

Exploring the Impact of Firefighter Trainee Fitness on Academy Graduation or Release.

ABSTRACT: Lockie, RG, Orr, RM, Montes, F, and Dawes, JJ. A research note exploring the impact of firefighter trainee fitness on academy graduation or release. J Strength Cond Res 38(5): 999-1003, 2024-This study investigated the impact of fitness test performance on firefighter trainee ability to graduate an academy using ordinal logistic generalized linear models. Retrospective analysis was conducted on trainee data ( N = 686) from one fire department who completed an occupational physical ability test (OPAT) that included the following: Illinois agility test (IAT); push-ups; pull-ups; leg tucks; maximal aerobic capacity (V̇ o2 max); backward overhead 4.54-kg medicine ball throw (BOMBT); 10-repetition maximum deadlift; and 91.44-m farmer's carry. Data were recorded in raw and scaled scores based on internal scoring (tests scored from 0 to 100; maximum total OPAT score of 800). Trainees were split into graduated ( n = 576) or released ( n = 110) groups. Data were analyzed through ordinal logistic generalized linear models ( p < 0.05). Raw and scaled scores were investigated separately, with odds ratios (OR) and confidence intervals (CI) produced. Regarding raw scores, there was a difference in the odds of graduating relative to the IAT (OR = 1.357; CI = 1.047-1.760; p = 0.021), BOMBT (OR = 0.744; CI = 0.628-0.882; p < 0.001), and V̇ o2 max (OR = 0.907; CI = 0.862-0.954; p < 0.001). For scaled scores, there was a difference in the odds of graduating relative to the points attained for the BOMBT (OR = 0.985; CI = 0.972-0.999; p = 0.032), deadlift (OR = 0.982; CI = 0.968-0.995; p = 0.008), and total OPAT (OR = 0.994; CI = 0.988-1.000; p = 0.047). Change-of-direction speed (IAT), total-body power (BOMBT), aerobic fitness (V̇ o2 max), lower-body strength (deadlift), and overall fitness (total OPAT points) impacted the odds of trainee fire academy graduation. The IAT presented as the largest impacting variable where, for every unit increase in time (i.e., a slower IAT), there was 1.36 greater chance of a trainee being released from the academy.

Expanding Research on Firefighter Trainee Fitness, Reasons for Academy Release, and the Predictive Capabilities of Fitness Tests.

ABSTRACT: Lockie, RG, Orr, RM, Montes, F, and Dawes, JJ. Expanding research on firefighter trainee fitness, reasons for academy release, and the predictive capabilities of fitness tests. J Strength Cond Res 38(4): 724-733, 2024-Firefighter trainees need a level of fitness to be admitted to and complete a training academy. Fitness could indicate a trainee's likelihood of graduation, in addition to their reasons for release. This study determined fitness differences between firefighter trainees who graduated (GRAD) from academy or were released because of injury (RELI), performance test failures (RELP), or resignation (RELR), and whether fitness predicted graduation. Occupational physical ability test (OPAT) data for 686 trainees were analyzed, including: Illinois agility test; push-ups; pull-ups; leg tucks; maximal aerobic capacity (V̇O2max); backward overhead medicine ball throw; 10-repetition maximum deadlift; and farmer's carry. Raw and scaled (based on internal scoring) scores were recorded. Trainees were split into GRAD (n = 576), RELI (n = 33), RELP (n = 66), and RELR (n = 11) groups. A 1-way ANOVA with Bonferroni post hoc calculated between-group differences. Stepwise linear regression determined whether fitness predicted group inclusion. Receiver operating curves and area under the curve (AUC) derived test accuracy for predicting academy release. The GRAD group was superior (p ≤ 0.04) to the RELI group in all tests except push-ups, pull-ups, and farmer's carry; RELP group in all tests except the farmer's carry; and RELR group in V̇O2max, deadlift, and total OPAT score. Select fitness tests could predict inclusion in each group, although the explained variances were low (∼1-11%). Raw V̇O2max (AUC = 0.71) and total OPAT score (AUC = 0.74) had acceptable prediction accuracy. Fitness influenced academy graduation and reasons for release. Scaled scores could predict group inclusion in this department; V̇O2max and total OPAT score provided the most accurate predictors for release.

Biochemical and Hormone Markers in Firefighters: Effects of "Search, Rescue, and Survival Training" and Its Recovery.

ABSTRACT: Ponce, T, Mainenti, MRM, de Barros, T, Cahuê, FLC, Fernanda, C, Piazera, BKL, Salerno, VP, and Vaisman, M. Biochemical and hormone markers in firefighters: effects of "search, rescue, and survival training" and its recovery. J Strength Cond Res 38(4): e189-e201, 2024-This study aimed to evaluate the hormonal and biochemical responses in military firefighter cadets to a search, rescue, and survival training (SRST) course. Forty-three male volunteers participated in the SRST over 15 days consisting of intense physical effort, sleep deprivation, and a survival period with food deprivation. At 3 timepoints (baseline, SRST, and 1 week rec), subjects submitted to blood collections, body composition examinations, physical performance evaluations, and cognitive function tests. After the SRST, lower values were registered for testosterone (764.0; 565.1-895.0 to 180.6; 133.6-253.5 ng·dl -1 ) and insulin-like growth factor-1 (IGF-1) (217; 180-238 to 116; 102-143 ng·ml -1 ). Increases were observed for cortisol (9.7; 8.2-11.7 to 18.3; 16.5-21,2 µg·dl -1 ), growth hormone (GH) (0.11; 0.06-0.20 to 2.17; 1.4-3.4 ng·ml -1 ), CP, GSSG, lactate dehydrogenase, alanine aminotransferase, and aspartate aminotransferase as well as the antioxidant response of superoxide dismutase and glutathione peroxidase. The values of gamma-glutamyl transferase were reduced. After 1 week of recovery, levels of GH, creatine kinase, GSH, and GSSG returned to baseline values ( p < 0.05). Vertical jump performance presented a regular positive correlation with testosterone (rho = 0.56 and p < 0.0001) and a strong negative correlation with cortisol (rho = -0.61 and p < 0.0001). Body fat showed a regular and positive correlation with both testosterone and IGF-1. We conclude that participation in the SRST caused significant hormonal and biochemical changes in individuals that correlated with a loss in physical performance. Importantly, the results suggest the need for longer recovery times before a return to normal military duties.