The Effects of Fire Academy Training and Probationary Firefighter Status on Select Basic Health and Fitness Measurements

Changes in Dynamic Balance Ability Among Firefighter Recruits: A Longitudinal Cohort Study

ABSTRACT

Cornell, DJ, Gnacinski, SL, and Ebersole, KT. Changes in dynamic balance ability among firefighter recruits: A longitudinal cohort study. J Strength Cond Res 38(4): 734-741, 2024-It has been suggested that enhanced balance ability may mitigate the high musculoskeletal injury (MSKI) rate among firefighters, but the longitudinal changes in dynamic balance ability within this tactical athlete population have yet to be characterized. The purpose of this study was to examine the changes in dynamic balance ability of a cohort population of firefighter recruits completing a training academy and their probationary period as active-duty firefighters. Twenty-seven male firefighter recruits completed the modified Star Excursion Balance Test (mSEBT) at the beginning (W1) and at the end of their training academy (W14) and after completing their probationary period as active-duty firefighters (W38). After controlling for age and changes in body fat (BF) over time, significant changes in mSEBTANT ( p < 0.001), mSEBTPL ( p = 0.015), mSEBTPM ( p < 0.001), and mSEBTCOMP ( p = 0.003) were observed across time. Although mSEBTPL performance significantly increased ( p = 0.033) in from W1 to W14, significant decreases in all mSEBT reach directions were observed from W14 to W38 ( p < 0.05), with mSEBTANT ( p < 0.001) and mSEBTCOMP ( p = 0.002) also significantly decreasing from W1 to W38. However, the frequency of right vs. left asymmetries (>4 cm) did not significantly change over time in any mSEBT reach direction ( p > 0.05). Irrespective of age or changes in BF, minimal changes in the dynamic balance ability of firefighter recruits were observed during their training academy, but significant decreases in balance ability were noted by the end of their probationary period.

Effects of implementing a mandatory and consequential annual fitness assessment in a fire department over the initial 4-year period

BACKGROUND

Despite the physical nature of the occupation many firefighters have low levels of physical fitness which is associated with poor performance of occupational tasks and increased injury rates. For many fire departments an initial step in promoting health and wellness within the department is to conduct annual fitness testing.

OBJECTIVE

To examine the effects of implementing a consequential fitness assessment within a fire department.

METHODS

A retrospective repeated measures design was used to analyze annual fitness assessment data of professional firefighters (n = 1415) from 2019 to 2022 within a large urban fire department located in the mid-Atlantic region of the United States. The fitness tests included assessments of pull-ups, push-ups, sit-ups, aerobic capacity, and body composition. Repeated measure analyses of variances (ANOVAs) assessed the effect of year and a 2-way ANOVA was conducted to investigate the effects of sex and age on fitness measures on 2022 data.

RESULTS

All fitness measures were found to be maintained over the 4-year period. Significant main effects of age and sex across all fitness measures, but no significant interactions were found. Older firefighters (50 + years) exhibited lower performance (p <  0.001, d >  0.80) on muscular fitness assessments than young firefighters (20-29 years). A large effect of sex (males >  females) was found for pull-ups (d = 1.04), push-ups (d = 1.23), and aerobic capacity (d = 1.38).

CONCLUSIONS

The results suggest that implementing a consequential fitness assessment could help maintain firefighters' fitness levels over a multi-year period.

Surviving & Thriving; a healthy lifestyle app for new US firefighters: usability and pilot study protocol

In the United States (US), new firefighters' fitness and health behaviors deteriorate rapidly after fire academy graduation. Over the long-term, this increases their risks for chronic diseases. This study protocol describes the proposed usability testing and pilot study of a newly designed and developed healthy lifestyle smartphone app, "Surviving & Thriving", tailored towards young US firefighters. "Surviving & Thriving" will provide interactive educational content on four lifestyle factors; nutrition, sleep, physical activity, and resilience, and include a personalized journey, habit tracker, and elements of gamification to promote engagement and long-term healthy behavior change. The first phase of the app development entails alpha testing by the research team and pre-beta testing by a fire service expert panel which will help refine the app into a pre-consumer version. Upon completion of the full app prototype, beta 'usability' testing will be conducted among new fire academy graduates from two New England fire academies to collect qualitative and quantitative feedback via focus groups and satisfaction surveys, respectively. A last phase of piloting the app will evaluate the app's efficacy at maintaining/improving healthy lifestyle behaviors, mental health metrics, and physical fitness metrics. We will also evaluate whether firefighters' perceived "health cultures" scores (ratings of each fire station's/fire department's environments as to encouraging/discouraging healthy behaviors) modify the changes in health metrics after utilizing the app for three to six months. This novel user-friendly app seeks to help new firefighters maintain/improve their health and fitness more effectively, reducing their risk of lifestyle-related chronic disease. Firefighters who can establish healthy habits early in their careers are more likely to sustain them throughout their lives.

Physical Training Programs for Tactical Populations: Brief Systematic Review

This review aims (i) to identify and analyze the physical training programs used for tactical personnel (TP) and (ii) to understand the effects of physical training programs on the health and fitness, and occupational performance of tactical personnel. A literature search used the keywords 'Physical Training Program', 'Police', 'Law Enforcement', and 'Firefighter'. A total of 23 studies out of 11.508 analyzed were included. All studies showed acceptable methodological quality in assessing physical fitness (PF), and training programs' effect sizes (Cohen's d) on PF attributes were calculated. The results showed that physical training programs (duration > four weeks) can improve (medium-to-large effects) (i) measures of physical fitness and (ii) performance in simulations of occupationally specific tasks. This review provides summary information (i) to help select (or adjust) physical training programs for TP and (ii) to clarify the effect of different occupational-specific training interventions on fitness measures and health-related parameters for TP.

Lifestyle and environmental factors may induce airway and systemic inflammation in firefighters

Health status depends on multiple genetic and non-genetic factors. Nonheritable factors (such as lifestyle and environmental factors) have stronger impact on immune responses than genetic factors. Firefighters work is associated with exposure to air pollution and heat stress, as well as: extreme physical effort, mental stress, or a changed circadian rhythm, among others. All these factors can contribute to both, short-term and long-term impairment of the physical and mental health of firefighters. Increased levels of some inflammatory markers, such as pro-inflammatory cytokines or C-reactive protein (CRP) have been observed in firefighters, which can lead to local, acute inflammation that promotes a systemic inflammatory response. It is worth emphasizing that inflammation is one of the main hallmarks of cancer and also plays a key role in the development of cardiovascular and respiratory diseases. This article presents possible causes of the development of an inflammatory reaction in firefighters, with particular emphasis on airway inflammation caused by smoke exposure.

Cardiometabolic Biomarkers and Habitual Caffeine Consumption Associate with the Adverse Ambulatory Blood Pressure Response to Strenuous Physical Exertion among Firefighters

Caffeine has beneficial effects on firefighter job performance reducing fatigue and improving psychomotor vigilance. However, excessive caffeine intake may raise blood pressure (BP) following a bout of acute exercise among adults with elevated BP. The influence of caffeine intake on the ambulatory BP (ABP) response to vigorous physical exertion among firefighters has not been studied. In this sub-study we conducted secondary statistical analyses from a larger clinical trial (NCT04514354) that included examining the influence of habitual caffeine intake, and cardiometabolic biomarkers shown to influence BP, on the ABP response following a bout of sudden vigorous exertion over 19 h among firefighters. Previously, we found high amounts of calcium and sodium intake raised BP following a bout of acute exercise among adults with elevated BP. Thus, other secondary aims were to examine the influence of habitual calcium and sodium intake, and cardiometabolic biomarkers have shown to influence BP, on the ABP response following sudden vigorous exertion over 19 h among firefighters. Firefighters (n = 15) completed a Food-Frequency Questionnaire assessing habitual dietary intake over the past year. They randomly completed a maximal graded exercise stress test (GEST) and non-exercise CONTROL on separate non-workdays leaving the laboratory wearing an ABP monitor for 19 h. Prior to and immediately after the GEST, fasting venous blood was collected to measure lipid-lipoproteins, c-reactive protein, and blood glucose. Height and weight were taken to calculate body mass index. Repeated measures ANCOVA tested if the ABP response differed after GEST vs. CONTROL. Linear mixed models examined the relationships among caffeine, calcium, sodium, cardiometabolic biomarkers, and the ABP response following GEST vs. CONTROL. Firefighters were middle-aged (40.2 ± 9.5 year), overweight (29.0 ± 3.9 kg/m2) men with elevated BP (124.1 ± 10.3/79.6 ± 11.5 mmHg) who consumed 542.0 ± 348.9 mg of caffeine/day, about ~50% more than the dietary reference intake. Unexpectedly, systolic ABP was higher by 18.0 ± 6.7 mmHg and diastolic ABP by 9.1 ± 5.4 mmHg (ps < 0.01) over 19 h following GEST vs. CONTROL. We found 24% of the variance in the adverse ABP response to maximal physical exertion was explained by caffeine intake, and when combined with c-reactive protein, non-high-density lipoprotein-cholesterol, body mass index, blood glucose, and resting heart rate, up to 74% of the variability in the ABP response was explained. Additionally, we found calcium (ps < 0.001) and sodium (p < 0.0001) intake each explained up to 24% of the ABP response. Further investigation is needed in a larger, more diverse sample of firefighters to better establish how caffeine contributes to the adverse BP response to strenuous physical exertion.

Blood Pressure Responses in Firefighters: A Review

Blood pressure (BP) responses are controlled by various factors and understanding how BP changes is important to occupational health. This paper presents a review of the literature that reports BP responses in the firefighter population. Hypertension is one of the main risk factors underlying the pathophysiology of cardiovascular disease (CVD), and cardiac incidents remain the leading cause of line-of-duty deaths in firefighters. Risk factors for line-of-duty deaths include obesity, previous or underlying heart disease, and hypertension. The occupation of firefighting is one of the most hazardous and dangerous jobs, yet over 50 % of firefighters are volunteers. Tactical operations and the hazardous nature of firefighting are exposures that influence stress responses and, therefore, affect BP. In fact, hypertension in firefighters often remains undocumented or undiagnosed. CVD risk and elevated BP in tactical populations, like firefighters, maybe a combination of physical and emotional stress due to the nature of the job. Cross-sectional studies have reported that firefighters have higher levels of BP and higher rates of hypertension compared to civilians. Interestingly, there is a limited amount of research that reports BP values before and after firefighting- related activities, and very few studies on interventional changes in BP. Here, we synthesize the literature on firefighting and provide a summary of the studies that report pre- and post- BP levels that relate to CVD risk factors, occupational factors, firefighting activities, and the data on exercise training and BP. More studies are needed that examine BP in firefighters and report on the changes in BP with occupational activities.

The Validity of Virtual Courage for Trainees in High-Risk Occupations

Background

Employees in high-risk occupations are exposed to tremendous work stress that hinders organizational effectiveness and personal mental health. Based on positive psychology, courage can be considered a protective factor that buffers the adverse effect of high-risk surroundings on employees. However, little is known about the way courage is simulated or evaluated in response to safety concerns. Virtual reality (VR) is an accessible tool for courage simulation due to its immersive qualities, presence and interactive features and may provide a promising pathway to achieve a scientific, accurate and ecologically valid evaluation of high-risk employees.

Methods

The sample consisted of 51 high-risk employees who were recruited voluntarily. Before and after experiencing the VR courage scenarios, the participants completed the VR features questionnaire, the Physical Courage at Work Scale (PCWS), the Courage Measure (CM), and the Positive and Negative Affect Scale (PANAS). During the process of watching the VR courage scenarios, the participants’ heart rate and skin conductance at resting-state baseline and during virtual courage scenarios were recorded through HTC VIVE Pro Eye and BioGraph Infiniti 8.

Results

The results support the hypothesis and reveal that the interaction, immersion and presence scores of the scenarios were all significantly higher than the median 4 points. The score for the CM in the posttest was significantly higher than that in the pretest. The scared and afraid scores for the posttest were significantly higher than those for the pretest. The heart rate and skin conductance of each scenario showed an increase compared with the baseline. The Pearson’s correlation between physiological indicators and the score of the PCWS was 0.28~0.54.

Conclusion

This study developed virtual courage for high-risk occupations based on well-established theory and VR technology. Experimental data revealed that the paradigm conformed to the requirements of VR features and was able to activate fear and evoke the quality of courage. Thus, the virtual courage paradigms have good validity in simulating scenarios for high-risk employees, which might accelerate organizational effectiveness while buffering working stress.

Effects of a healthy lifestyle intervention and COVID-19-adjusted training curriculum on firefighter recruits

There are knowledge gaps regarding healthy lifestyle (HLS) interventions in fire academy settings and also concerning the impacts of the pandemic on training. We enrolled fire recruits from two fire academies (A and B) in New England in early 2019 as the historical control group, and recruits from academies in New England (B) and Florida (C), respectively, during the pandemic as the intervention group. The three academies have similar training environments and curricula. The exposures of interest were a combination of (1) an HLS intervention and (2) impacts of the pandemic on training curricula and environs (i.e. social distancing, masking, reduced class size, etc.). We examined the health/fitness changes throughout training. The follow-up rate was 78%, leaving 92 recruits in the historical control group and 55 in the intervention group. The results show an HLS intervention improved the effects of fire academy training on recruits healthy behaviors (MEDI-lifestyle score, 0.5 ± 1.4 vs. − 0.3 ± 1.7), systolic blood pressure (− 7.2 ± 10.0 vs. 2.9 ± 12.9 mmHg), and mental health (Beck Depression score, − 0.45 ± 1.14 vs. − 0.01 ± 1.05) (all P < 0.05). The associations remained significant after multivariable adjustments. Moreover, a 1-point MEDI-lifestyle increment during academy training is associated with about 2% decrement in blood pressures over time, after multivariable adjustments (P < 0.05). Nonetheless, the impacts of pandemic restrictions on academy procedures compromised physical fitness training, namely in percent body fat, push-ups, and pull-ups.

Retrospective Longitudinal Evaluation of Male Firefighter's Body Composition and Cardiovascular Health

OBJECTIVE

Describe firefighter body composition and cardiovascular health as a function of age.

METHODS

217 male firefighters with 1922 distinct evaluations over 23-years were included in this retrospective analysis. The firefighters had their height, mass, six-site skin-fold, blood pressure, and resting heart rate measured annually. Linear mixed models were used to analyze the effect of age. Significance was set to P < 0.05.

RESULTS

With each 1-year increase in age, mass (0.42 kg, P < 0.001), body mass index (0.13 kg m-2, P < 0.001), body fat percentage (0.18%, P < 0.001), fat mass (0.25 kg, P < 0.001), and fat free mass (0.15 kg, P < 0.001) increased. Systolic blood pressure (-0.09 mm Hg, P = 0.263), diastolic blood pressure (0.05 mm Hg, P = 0.308), and resting heart rate (0.07 beats min-1, P = 0.291) did not change.

CONCLUSIONS

Interventions to maintain healthy body composition are critical to reduce sudden cardiovascular related death risk.

Functional Movement Quality of Firefighter Recruits: Longitudinal Changes from the Academy to Active-Duty Status

Approximately half of the injuries experienced by firefighters consist of musculoskeletal injuries (MSKIs). Functional movement quality may be associated with MSKI risk within this tactical athlete population. Previous research indicates that measures of body composition change among firefighter recruits progressing from academy training through active-duty service, but similar changes in functional movement quality have yet to be examined. The purpose of this study was to describe longitudinal changes in functional movement quality of firefighter recruits. Body mass index (BMI), body fat (BF), and Functional Movement Screen (FMS) data were collected from 26 male firefighter recruits at the onset (W1) and completion (W14) of their training academy, and at the completion of their probationary period of active-duty service (W38). After adjusting for changes in BMI and BF across time, significant changes (ps < 0.05) in Composite FMS scores were identified, with significant increases in from W1 to W14 and from W14 to W38, as well as an overall increase from W1 to W38. These results suggest that the development of firefighter-specific skills can decrease the MSKI risk of firefighter recruits by facilitating enhanced functional movement competencies, particularly during tasks that require single-leg movement and core strength and stability.