Cardiorespiratory fitness predicts cardiovascular risk profiles in career firefighters

The influence of vigorous physical exertion on cardiac demand under conditions of daily living among firefighters with elevated blood pressure

BACKGROUND

Firefighters have a high prevalence of cardiovascular disease. The poor heart health of firefighters is implicated in their increased risk of sudden cardiac death (SCD). Exercise may be protective against SCD partially due to the immediate blood pressure (BP) reductions of 5-8 mmHg following exercise, termed postexercise hypotension (PEH) OBJECTIVES: To examine PEH under ambulatory conditions after a maximal cardiopulmonary exercise test (CPET) among career firefighters METHODS: Firefighters (n = 19) completed a maximal CPET and non-exercise control (CONTROL) in random order on separate non-workdays and left the laboratory instrumented to an ambulatory BP (ABP) monitor. Ambulatory systolic BP (ASBP), diastolic BP (ADBP), and heart rate (AHR) were recorded at hourly intervals over 19hr. The ambulatory rate pressure product (ARPP) was calculated as ASBPxAHRx10-3 at each hourly interval. Repeated measures ANCOVA tested if the ABP, AHR, and ARPP responses differed after CPET vs CONTROL over 19hr RESULTS: Firefighters were middle-aged (39.5 ± 8.9 yr), overweight (29.2 ± 4.0 kg/m2) men with elevated BP (123.1 ± 9.6/79.8 ± 10.4 mmHg), while resting HR (67.7 ± 11.3 bpm) and RPP (8.4 ± 1.7mmHg*bpm*10-3) were in normal ranges. ASBP (16.6 ± 5.7 mmHg) and ADBP (3.1 ± 4.6 mmHg) increased after the CPET vs CONTROL over 19hr (ps<0.01), as did AHR (9.4 ± 7.9 bpm, p = 0.02) and ARPP (2.5 ± 1.1mmHg*bpm*10-3, p < 0.01).

CONCLUSIONS

Unexpectedly, the firefighters exhibited postexercise hypertension rather than PEH. The increases in ABP and AHR we observed indicated a sustained increase in cardiac demand. Further investigation is needed to confirm our findings and determine whether the adverse hemodynamic responses we observed contribute to the high prevalence of SCD that firefighters experience on the job.

Cardiorespiratory Fitness Is Not Associated with Cardiovascular Disease Risk in Firefighters: A Cross-Sectional Study in South African Firefighters

Cardiovascular disease (CVD) risk factors are frequently reported among firefighters, yet no studies have compared these factors between male and female firefighters, specifically from a low- to middle-income country (LMIC). This study aimed to determine the prevalence of CVD risk factors and their relationship with cardiorespiratory fitness (VO2max) in 254 active career firefighters (mean age: 42.6 ± 7.8 years). The assessments included anthropometry, blood pressure, blood glucose, cholesterol, triglycerides, and VO2max. The results indicated that 48.0% and 51.8% of females and males were pre-hypertensive, respectively. Hypertension was identified in 15.8% of the firefighters. According to body mass index (BMI), 37.3% of males and 25% of females were found to be overweight, while an additional 44.9% of males and 45.7% of females were classified as obese. Only 17.3% of males and 18.2% of females were found to be of normal weight. These findings were corroborated by categories of central obesity using waist circumference (WC), which were 47.7% for males and 41.6% for females. Low HDL-C was found in 95.2% of males and 86.4% of females, with 28.3% of males also having elevated triglyceride levels (TG). VO2max was "excellent" in 48.8% of males and 12.6% of females, though it had no significant association with most CVD risk factors. The only notable link was a small correlation between VO2max and triglycerides (r = -0.215; p = 0.001). These findings suggest that while cardiorespiratory fitness may have no impact, additional factors likely contribute to the cardiovascular health of firefighters, necessitating the need for comprehensive health and fitness programmes.

Effect of Cardiorespiratory Fitness Level on Physiological Responses and Task Performance During a High-Rise Firefighting Task

OBJECTIVES

To determine the impact of cardiorespiratory fitness (CRF) on physiological and performance outcomes during a 120-m vertical high-rise ascent in firefighters with CRF levels at or above (higher-fit) and below (lower-fit [LF]) the national recommended minimum physical employment standard (V˙O 2 max 42.3 mL·kg -1 ·min -1 ).

METHODS

Twenty-eight firefighters completed two high-rise firefighting trials (continuous and discontinuous ascent with predetermined 1-minute rest breaks). Task time, heart rate, ratings of perceived exertion, core body temperature, and thermal comfort were recorded at predetermined elevations.

RESULTS

Task time was significantly longer in both trials for the LF group. Ratings of perceived exertion and thermal comfort were also significantly higher in the LF group, with three times more LF firefighters being unable to complete the ascent without sounding their low-air alarm.

CONCLUSIONS

Higher CRF improves performance and efficiency during stair-climbing in simulated high-rise firefighting tasks.

Relationship between Simulated Fire Suppression Activities and Acute Cardiac and Respiratory Events in Firefighters

Cardiac deaths account for the largest share of on-duty firefighter deaths. To help ensure duty fitness and minimize injury risk, many fire departments require the passing of an annual physical ability test, consisting of a battery of simulated fire suppression activities (sFSAs). The purpose of the study was to determine the relationship of sFSA performance to acute cardiac and respiratory events (ACREs) and the effect that estimated VO2max has on sFSA performance. The study was retrospective. As part of an annual physical ability test, five timed sFSAs were performed, summed for a composite time, and categorized into three performance levels (fast, moderate, and slow). Estimated VO2max was determined using the Forestry Step Test. A significant (p = 0.023) linear trend was observed with higher sFSA performance times being associated with a higher proportion of firefighters going on to suffer an ACRE. The estimated VO2max was significantly (p < 0.001) higher in the fast group compared to the slow group. There was not a significant (p = 0.70) difference in estimated VO2max between the moderate and slow groups. Estimated VO2max performance and sFSA performance were significantly correlated, with rs(488) = -0.272 and p < 0.001. Poorer sFSA performance was found to be associated with a higher proportion of ACREs. The results suggest that sFSA performance may be a valid indicator of ACRE injury risk and aerobic capacity.

Firefighter Health: A Narrative Review of Occupational Threats and Countermeasures

Structural firefighters are responsible for protecting properties and saving lives during emergency operations. Despite efforts to prepare firefighters for these hazardous occupational demands, the unfortunate reality is that the incidence of health morbidities is increasing within the fire service. Specifically, cardiovascular disease, cancer, and mental health disorders are among the most documented morbidities in firefighters. Pubmed and Google Scholar search engines were used to identify peer-reviewed English language manuscripts that evaluated firefighters' occupational health threats, allostatic factors associated with their occurrence, and evidence-based strategies to mitigate their impact. This narrative review provides fire departments, practitioners, and researchers with evidence-based practices to enhance firefighters' health.

Climbing the Ranks: A Study of Firefighter Health Disparities

The fire service command structure encompasses recruit, incumbent firefighter, and officer positions. The purpose of this study was to quantify the effect of rank (recruits, incumbent firefighters, and officers) on health and physical ability characteristics within the fire service. Retrospective data from thirty-seven recruits (age = 29 ± 5 yrs, BMI = 26.5 ± 2.3 kg/m2); eighty-two incumbent firefighters (age = 30 ± 7 yrs, BMI = 28.8 ± 4.3 kg/m2); and forty-one officers (age = 41 ± 6 yrs, BMI = 28.6 ± 4.3 kg/m2) from a single department were used. Participants completed body composition tests (i.e., body fat percentage [%BF] and body mass index [BMI]), an air consumption test (ACT), and cardiopulmonary exercise testing. The ACT consisted of 10 standardized tasks. Five separate one-way analyses of co-variance (ANCOVA) were calculated, accounting for age. Partial eta squared statistics were calculated and Bonferroni-corrected post-hoc analyses were employed. The results demonstrated a significant effect of rank on %BF (F = 9.61, p < 0.001, η2 = 0.10); BMI (F = 3.45, p = 0.02, η2 = 0.05); relative VO2MAX (F = 12.52, p < 0.001; η2 = 0.11); and HRMAX (F = 18.89, p < 0.001, η2 = 0.03), but not on ACT time (F = 0.71, p = 0.55, η2 = 0.01). These outcomes suggest there are variations in anthropometric and physiological metrics of health across firefighter ranks. Administrators should be aware how these markers of health may vary across firefighter ranks.

Exploring wearable technology use and importance of health monitoring in the hazardous occupations of first responders and professional drivers

OBJECTIVES

Hazardous materials (HAZMAT) pose risks to the health and safety of professionals involved with transportation and emergency responses. Two distinct occupational groups that encounter HAZMAT events are first responders and professional drivers. Wearable technology is a tool that can assist with monitoring the health of professionals involved in HAZMAT events. The aim of this study was to compare and evaluate the perceptions of first responders and professional drivers on wearable technology and attitudes toward health monitoring.

METHODS

A survey was administered to first responders (n = 112) and professional drivers (n = 218). Statistical approaches included bivariate analysis, latent class analysis, logistic regression analysis, and path analysis for the variables of interest.

RESULTS

There were significant differences between the groups in perceptions of the benefits of monitoring certain health indicators. Professional drivers were more likely to have a history of wearable technology use compared with first responders (odds ratio [OR] = 10.1; 95% CI, 4.42-22.9), reported greater exposure to HAZMAT (OR = 4.32; 95% CI, 2.24-8.32), and were more willing to have their health data monitored by someone other than themselves (OR = 9.27; 95% CI, 3.67-23.4). A multinomial regression model revealed that occupation was not a significant predictor of class preference for acceptance of monitoring specific health indicators.

CONCLUSIONS

Occupation appeared to be important but further analysis uncovered that characteristics of individuals within the occupations were more salient to the use of wearable technology. HAZMAT exposure, someone else monitoring health data, and experience with wearable technology use were found to be important factors for perceptions about benefits of health monitoring with wearable technology.

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.

Identifying the most important, frequent, and physically demanding tasks of Brazilian firefighters

This study aimed to identify the most important, frequently performed, and physically demanding tasks performed by Brazilian firefighters and to identify tasks that could be used to assess physical fitness. A subjective task analysis was conducted. Five hundred twenty-four firefighters (84% male; 16% females) responded to an online survey and rated 37 tasks across three domains (most important, most frequent, and most physically demanding). A dichotomous decision analysis was used to inform the proposed physical fitness tests. Wildland firefighting tasks presented the highest overall mean rate. Traffic control was considered the most important and frequently performed task. Lifeguard rescue was considered the most physically demanding task. The dichotomous analysis identified 14 essential tasks (seven structural firefighting and seven automobile accidents). The tasks identified may be helpful in developing criterion physical fitness tests and training programs related to firefighters' demands.Practitioner summary: The unpredictability, variability, and dangerousness of firefighting make it challenging to observe the physical demands imposed on firefighters. A subjective task analysis was conducted to identify essential tasks performed by Brazilian firefighters. Wildland firefighting, lifeguard rescue, automobile accidents, and structural firefighting tasks were the most important, frequent, and physically demanding.

The effect of mild to moderate COVID-19 infection on the cardiorespiratory fitness of firefighters

Introduction

An adequate level of cardiorespiratory fitness (CRF) is critical for firefighters to perform the strenuous and physiologically demanding work of firefighting safely and effectively. The coronavirus disease 2019 (COVID-19) has been shown to negatively impact CRF in both the acute phase and longer-term following infection. This study aimed to determine changes to the CRF of firefighters pre- to post-mild to moderate COVID-19 infection and to investigate the impact of days past COVID-19 infection on change in CRF.

Methods

CRF measures from cardiopulmonary exercise testing (CPET) at annual occupational health exams that occurred pre-COVID-19 infection in 2019 were obtained for firefighters from seven Arizona fire departments. Measures were compared to CPET evaluations from annual health exams the following year in a cohort of firefighters who self-reported mild to moderate illness following COVID-19 infection between exams.

Results

Among a cohort of 103 firefighters, mean age 40 ± 9 years, CRF [as measured by peak oxygen consumption (VO2)] declined by an average of 2.55 ml·kg-1·min-1 or 7.3% (d = -0.38, p < 0.001) following COVID-19 infection (mean time from COVID-19 infection to CPET was 110 ± 78 days). The number of days past COVID-19 infection showed a small, yet significant, relationship to peak VO2 (r = 0.250, p = 0.011). Estimated marginal effects indicated that when biological sex, age, and BMI are controlled for, predicted peak VO2 returned to pre-COVID-19 values ~300 days after COVID-19 infection.

Conclusion

Peak VO2 (ml·kg-1·min-1) declined 7.3% among firefighters an average of 110 days past reporting mild to moderate COVID-19 infection. This decrease has implications for the operational readiness and safety of firefighters.

Association between Physical Fitness and Cardiovascular Health in Firefighters

Firefighters perform strenuous work in dangerous and unpredictable environments requiring optimal physical conditioning. The aim of this study was to investigate the association between physical fitness and cardiovascular health (CVH) in firefighters. This cross-sectional study systematically recruited 309 full-time male and female firefighters between the ages of 20 to 65 years in Cape Town, South Africa. Physical fitness was assessed using absolute (abV̇O2max) and relative oxygen consumption (relVO2max), grip and leg strength, push-ups and sit-ups, sit-and-reach for flexibility and lean body mass (LBM). CVH encompassed age, smoking, blood pressure (BP), blood glucose, lipid profile, body mass index, body fat percentage (BF%), and waist circumference. Linear regressions and logistic regressions were applied. Multivariable analysis indicated that relVO2max was associated with systolic BP (p < 0.001), diastolic BP (p < 0.001), non-fasting blood glucose (p < 0.001), and total cholesterol (p = 0.037). Poor CVH index was negatively associated with relV̇O2max (p < 0.001), leg strength (p = 0.019), and push-ups (p = 0.012). Furthermore, age was inversely associated with V̇O2max (p < 0.001), push-up and sit-up capacity (p < 0.001), and sit-and-reach (p < 0.001). BF% was negatively associated with abV̇O2max (p < 0.001), grip and leg strength (p < 0.001), push-ups (p = 0.008), sit-ups (p < 0.001), and LBM (p < 0.001). Cardiorespiratory fitness, muscular strength, and muscular endurance were significantly associated with a better overall CVH profile.

Exploring First Responders' Use and Perceptions on Continuous Health and Environmental Monitoring

First responders lose their lives in the line of duty each year, and many of these deaths result from strenuous physical exertion and exposure to harmful environmental agents. Continuous health monitoring may detect diseases and alert the first responder when vital signs are reaching critical levels. However, continuous monitoring must be acceptable to first responders. The purpose of this study was to discover first responders' current use of wearable technology, their perceptions of what health and environmental indicators should be monitored, and who should be permitted to monitor them. The survey was sent to 645 first responders employed by 24 local fire department stations. A total of 115 (17.8%) first responders answered the survey and 112 were used for analysis. Results found first responders perceived a need for health and environmental monitoring. The health and environmental indicators that respondents perceived as most important for monitoring in the field were heart rate (98.2%) and carbon monoxide (100%), respectively. Overall, using and wearing monitoring devices was not age-dependent and health and environmental concerns were important for first responders at any stage of their career. However, current wearable technology does not seem to be a viable solution for first responders due to device expense and durability issues.

Association between Cardiovascular Disease Risk Factors and Cardiorespiratory Fitness in Firefighters: A Systematic Review and Meta-Analysis

Approximately 45% of on-duty related mortalities were due to sudden cardiac death, with many of these fatalities related to cardiovascular disease and overexertion, while performing emergency duties. Therefore, the aim of this systematic review was to determine the association between cardiovascular disease risk factors and cardiorespiratory fitness in firefighters. A literature search of PubMed, SCOPUS, Web of Science, Embase, EBSCOHost, and ScienceDirect was conducted; the Rayyan® intelligent systematic review tool was used to screen and select studies for inclusion. The appraisal tool for cross-sectional studies and the Critical Appraisal Skills Programme toolkit were used for methodological assessment of included studies. Data were analyzed using the Review Manager 5.3 and MedCalc® statistical softwares to determine the effects of obesity (Z = 10.29, p < 0.001) and aging (Z = 4.72, p < 0.001) on cardiorespiratory fitness. Furthermore, there was a significant effect for cardiorespiratory fitness level on systolic blood pressure (Z = 5.94, p < 0.001), diastolic blood pressure (Z = 2.45, p < 0.001), total cholesterol levels (Z = 3.80, p < 0.001), low-density lipoprotein cholesterol (Z = 4.44, p < 0.001), triglycerides (Z = 3.76, p < 0.001) and blood glucose concentration (Z = 4.78, p < 0.001). Cardiovascular disease risk factors and cardiorespiratory fitness were significantly and inversely associated in firefighters. Fire service departments should adopt behavioral intervention strategies to maintain optimum cardiovascular disease risk factor profiles and cardiorespiratory fitness among firefighters to ensure their occupational well-being.

Utilizing multimodal high-intensity interval training for a firefighter training academy during the COVID-19 pandemic

BACKGROUND

Firefighters typically undergo a 16-24-week training academy during which they perform a variety of traditional exercise programs such as cardiovascular, resistance, and concurrent training. Because of limited facility access, some fire departments seek alternative exercise programs, such as multimodal high-intensity interval training (MM-HIIT), which essentially combines resistance and interval training.

OBJECTIVE

The primary purpose of this study was to assess the effect of MM-HIIT on body composition and physical fitness in firefighter recruits who completed a training academy during the coronavirus (COVID-19) pandemic. A secondary purpose was to compare the effects of MM-HIIT to previous training academies that implemented traditional exercise programs.

METHODS

Healthy and recreationally-trained recruits (n = 12) participated in 2-3 days/week of MM-HIIT for 12 weeks and had several components of body composition and physical fitness measured before and after the program. Because of COVID-19-related gym closures, all MM-HIIT sessions were performed outdoors at a fire station with minimal equipment. These data were retroactively compared to a control group (CG) that previously completed training academies with traditional exercise programs.

RESULTS

Subjects in the MM-HIIT group significantly improved several components of body composition and fitness, including fat mass, fat-free mass, body fat percentage, aerobic capacity, and muscular endurance. Moreover, there were no significant differences for any dependent variable when MM-HIIT was compared to the CG.

CONCLUSION

These results suggest that MM-HIIT may serve as an effective substitute for traditional concurrent training paradigms that are typically used for firefighter academies.

Firefighters With Higher Cardiorespiratory Fitness Demonstrate Lower Markers of Cardiovascular Disease Risk

OBJECTIVE

High cardiorespiratory fitness (CRF) is associated with reduced markers of oxidative stress and cardiovascular disease (CVD) risk factors; however, this relationship has not been elucidated in firefighters. The purpose of this study was to examine differences in markers of CVD risk between firefighters who have either high or low levels of CRF.

METHODS

Forty-six firefighters participated in a maximal graded exercise test and a dual-energy x-ray absorptiometry scan and provided a fasted blood sample. V˙O 2max values were categorized based on American College of Sports Medicine guidelines to establish high- and low-fitness groups.

RESULTS

High fitness firefighters demonstrated significantly higher high-density lipoprotein cholesterol and lower markers of CVD risk: cholesterol, triglycerides, low-density lipoprotein cholesterol, insulin, homeostatic model assessment for insulin resistance, C-reactive protein, and advanced oxidation protein products concentrations.

CONCLUSION

Firefighters are encouraged to maintain high CRF to reduce risk of CVD.

Body Composition and Fitness Characteristics of Firefighters Participating in a Health and Wellness Program: Relationships and Descriptive Data

This study investigated body composition and fitness test relationships from firefighters participating in a health and wellness program and categorized firefighters according to population norms relative to sex and age. Data from 270 firefighters (men = 258, women = 12) were analyzed, including body composition (body mass index [BMI], body fat percentage [BF%], waist circumference [WC], waist-to-hip ratio) and fitness (sit-and-reach, grip strength, leg press, crunches, push-ups, maximal aerobic capacity [V̇O2max]) tests. Mann-Whitney U-test analysis (p < 0.05) showed that male firefighters had a greater WC, WHR, grip strength and leg press. Female firefighters had a greater BF% and better sit-and-reach. Partial correlations controlling for sex indicated 22/24 correlations between body composition and fitness were significant (r = -0.143--0.640). ~52% of firefighters were overweight, and 25% were Obesity Class I-III. ~76% had an increased risk of cardiovascular disease (CVD) considering BMI and WC. ~22% were fatter than average-to-overfat considering BF%. Most firefighters (73-94%) were good-to-excellent in sit-and-reach, grip strength, and push-ups; average-to-well above average in crunches; average-to-above average in leg press; and had good-to-superior V̇O2max. Although most firefighters had better fitness compared to the general population, many had increased CVD risk. The data highlighted the need for comprehensive approaches to improving firefighter health and decreasing CVD risk.

A Pilot Study on the Relationship between Cardiovascular Health, Musculoskeletal Health, Physical Fitness and Occupational Performance in Firefighters

Firefighters’ face life threatening situations and are frequently exposed to numerous physical, chemical, biological, ergonomic and psychosocial hazards. The purpose of this pilot study was to investigate the feasibility of conducting a large-scale study on cardiovascular and musculoskeletal health, physical fitness and occupational performance of firefighters. We conducted a cross-sectional pilot study by recruiting 36 firefighters. A researcher-generated questionnaire and physical measures were used to collect data on sociodemographic characteristics, cardiovascular and musculoskeletal health, physical fitness and occupational performance using a physical ability test (PAT). We documented a high equipment and intra-assessor reliability (r > 0.9). The potential logistic and/or administrative obstacles in the context of a larger study were discerned. Data were successfully retrieved using available equipment and survey instruments. Hypertension (30.6%) dyslipidaemia (33.3%), obesity (36.1%) and physical inactivity (66.7%) were the most prevalent cardiovascular disease risk factors. A significant difference between genders in total PAT completion time was also seen (p < 0.001). Cardiorespiratory fitness, lean body mass, grip strength and leg strength were significantly associated with occupational performance (p < 0.001). The pilot study supports the larger study feasibility and verified equipment and assessors’ reliability for research. Cardiovascular health, musculoskeletal health and physical fitness may be related to PAT performance.

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.

Effects of Cardiovascular Disease Risk Factors, Musculoskeletal Health, and Physical Fitness on Occupational Performance in Firefighters-A Systematic Review and Meta-Analysis

Background: Firefighting is a strenuous occupation, which necessitates that firefighters stay in good physical condition and maintain adequate cardiovascular and musculoskeletal fitness to perform their duties with minimal health and safety risks. The aim of this review is to determine the effects of cardiovascular disease risk factors, musculoskeletal health, and physical fitness on the occupational performance of firefighters. Methods: PubMed/Medline, SCOPUS, Web of Science, EBSCOHost, and ScienceDirect were searched without time-restriction. The appraisal tool for cross-sectional studies and the Critical Appraisal Skills Programme toolkit were used to conduct the methodological assessment. Data were analyzed using Review Manager 5.3, and MedCalc^® statistical software. Results: Age had a moderate effect on occupational performance (Z = 5.15, p < 0.001), whereas gender had a large effect size on occupational performance (Z = 4.24, p < 0.001). A significant moderate negative correlation was found between cardiorespiratory fitness and occupational performance (R = -0.584, p < 0.001). Significant low negative correlations were found between upper body endurance (R = -0.344, p < 0.001), abdominal endurance (R = -0.308, p < 0.001), grip strength (R = -0.421, p < 0.001), upper body strength (R = -0.318, p < 0.001), and lower body strength (R = -0.216, p = 0.020) and occupational performance. Conclusions: Aged firefighters with poor body composition and lower levels of physical fitness performed worse on all occupational performance tasks.

Cardiovascular Disease Risk Factors, Musculoskeletal Health, Physical Fitness, and Occupational Performance in Firefighters: A Narrative Review

Introduction

Firefighting is a strenuous occupation that requires firefighters to be in peak physical condition. However, many firefighters have risk factors for cardiovascular disease, impaired musculoskeletal health, and are not physically fit for duty, which all negatively impact their occupational performance. Therefore, the aim of this review is to determine the relationship between cardiovascular disease risk factors, musculoskeletal health, physical fitness, and occupational performance in firefighters.

Methods

The electronic databases PubMed, SCOPUS, and Web of Science were searched online via the library portal of the University of the Western Cape. Publications and grey literature between the years 2000 to present were used. In total, 2607 articles were identified; after the removal of duplicates 1188 articles were then screened, and were excluded for not meeting initial screening criteria. The remaining 209 full-text articles were screened based on the inclusion and exclusion criteria, where 163 articles were excluded. Only studies that were quantitative were included. This left 46 articles that were then finally included in the current narrative review.

Results

The current literature indicated that significant relationships existed between cardiovascular risk factors, musculoskeletal health, physical fitness, and occupational performance. The results indicated firefighters who were aged, obese, physically inactive, cigarette smokers, and unfit were at the highest risk for cardiovascular and musculoskeletal health complications, and unsatisfactory occupational performance. Musculoskeletal health complications significantly affected occupational performance and work ability and were related to physical fitness of firefighters. Most cardiovascular risk factors were related to physical fitness, and all physical fitness parameters were related to occupational performance in firefighters.

Conclusion

The overwhelming evidence in the current review established that physical fitness is related to occupational performance. However, the relationship between cardiovascular risk factors and musculoskeletal health in relation to occupational performance is less clear and still understudied. Significant gaps remain in the literature.

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.

Differences in Fitness between Firefighter Trainee Academy Classes and Normative Percentile Rankings

Fire academy training classes may have trainees with a range of different fitness capabilities. Documentation of trainee fitness could indicate the need for flexibility in physical training emphases. Therefore, data from six academy classes (males = 274; females = 31) were analyzed, including: Illinois agility test (IAT), push-ups, pull-ups, leg tucks, multistage fitness test, backwards overhead 4.54 kg medicine ball throw (BOMBT), 10-repetition maximum deadlift, and 18 kg kettlebell farmers carry. A one-way ANOVA, with the Bonferroni post hoc test, calculated between-class fitness differences. Normative fitness test data were produced via percentile ranks. Classes 5 and 6 had the most females (n = 15). Class 1 completed the IAT faster than all classes (p ≤ 0.009). Classes 1 and 4 had a further BOMBT distance than Classes 5 and 6, and Class 3 outperformed Class 6 (p ≤ 0.044). Class 4 completed more leg tucks than Class 5 (p = 0.047). Class 1 had a greater deadlift than Classes 3, 4, and 6, and Class 2 outperformed Classes 3–6 (p ≤ 0.036). Class 3 was slower in the farmers carry compared to all classes (p ≤ 0.002). Percentile rankings showed that most females (48–100%) were in the 0–29% rank. Staff should implement individualized programs where appropriate for trainees as cohort fitness differences exist. Female trainees may need targeted maximal strength and power development.

Fit to Teach?-Cardiorespiratory Capacity, Vitamin D3, and Ferritin in Physical Education Teachers With Specialization in Dance

ABSTRACT

Schmidt, M, Ohlendorf, D, Groneberg, DA, and Wanke, EM. Fit to teach?-Cardiorespiratory capacity, vitamin D3, and ferritin in physical education teachers with specialization in dance. J Strength Cond Res 35(4): 1156-1164, 2021-Numerous studies have shown that good cardiorespiratory capacity is of great importance for a healthy and long-term professional career as a dancer. Although the cardiorespiratory demands during teaching can reach into the submaximal intensity range, current data on the objective physical fitness of this occupational group are still missing. The aim of this pilot project was to determine selected cardiorespiratory parameters. In addition, measurements of the vitamin D3 (25(OH)D3) and iron balance as well as a subjective assessment of dance teachers' (DTs) fitness were performed. Twenty-one DTs (f: n = 18, m: n = 3) aged 48.2 ± 9.3 years were examined for cardiorespiratory performance within the framework of maximum bicycle spiroergometry. In addition, the self-perception of DTs' fitness was examined as well as the serum vit D3 levels and ferritin concentration in the blood. The cardiorespiratory fitness of DTs can be assessed as average (maximal oxygen consumption, V̇o2max = 29.5 ± 7.1 ml·k-1·min-1; physical working capacity, PWCmax = 165.0 ± 44.4). The DTs seemed to underestimate or overestimate their own capacity. Laboratory diagnostics showed that the 25(OH)D3 levels (21.8 ± 8.5 ng·ml-1) and serum ferritin values (102.4 ± 35.0 g·dl-1) were not optimal for almost the entire sample. In view of the physical occupational requirements, an increase in aerobic cardiorespiratory fitness by endurance-oriented basic training for DTs seems advisable. In addition, the substitution of vit D3 is worth being discussed.

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

PURPOSE

This study aimed to investigate changes in firefighter recruits' select health and fitness measurements, from academy training to the early probationary firefighter period.

METHODS

Firefighter recruits from two New England fire academies were followed up prospectively from enrollment at the academy to graduation after 15- to 16-wk training programs, and then for an average of 8 months as probationary firefighters. The participants' demographic, lifestyle, and mental health information was collected using a questionnaire. Body mass index, percent body fat, blood pressure, and push-ups were also measured at each time point. Furthermore, the academies tested the recruits on selected fitness measures (push-ups, pull-ups, and 1.5-mile running time) at academy entry, midtraining, and at graduation.

RESULTS

Ninety-two recruits consented and were included in the analyses. The recruits' percent body fat significantly decreased (median, 21.0%-18.2%) from baseline to graduation, and push-up capacity significantly improved (median, 34-53 per minute) in the same period, along with pull-ups and 1.5-mile running time. However, the recruits' blood pressure, both systolic and diastolic, increased significantly by an average of 3 mm Hg during the training. Those completing probationary follow-up (45/92 recruits) showed that most health/fitness improvements declined after graduation. From academy graduation to probationary follow-up, recruits' physical activity decreased and TV screen time increased significantly, leading to a lower healthy lifestyle score (median, 4-3). After multivariate adjustments, the recruits' diastolic blood pressure increased by 2 mm Hg per measuring time throughout the study period.

CONCLUSIONS

Fire academy training improved recruits' select health and fitness measurements, but the benefits dissipated as probationary firefighters, and blood pressures increased throughout the study period. Further interventions regarding blood pressure and to maintain training benefits after joining fire departments are warranted.

Higher cardiorespiratory fitness is strongly associated with lower cardiovascular risk factors in firefighters: a cross-sectional study in a German fire brigade

Previous studies have shown significant cardiovascular risks in firefighters and that they suffer from cardiovascular events, especially on duty. Otherwise, adequate cardiorespiratory fitness is considered to have a protective effect in reducing cardiovascular complications. Therefore, the study aimed to evaluate the association between cardiorespiratory fitness and cardiovascular risks factors in firefighters. We enrolled ninety-seven male German firefighters in this cross-sectional study of cardiorespiratory fitness and cardiovascular risk factors. We used spiroergometry testing to estimate oxygen consumption to determine cardiorespiratory fitness and to calculate metabolic equivalents. We evaluated cardiovascular risk factors included nicotine consumption, lipid profiles, body composition, resting blood pressure, and heart rate. We evaluated cardiovascular risk factors included nicotine consumption, lipid profiles, body composition, resting blood pressure and heart rate. The comparison of association between cardiorespiratory fitness and cardiovascular risk factors was performed by using χ²-test, analysis of variance, general linear regression with/without adjustment for age and body mass index (BMI). This study demonstrated a strong association between lower cardiovascular risk factors and higher cardiorespiratory fitness. There were significantly lower values for BMI, waist circumference, body fat percentage and resting systolic blood pressure, triglycerides, and total cholesterol (all p < 0.0443, age-adjusted) with increased cardiorespiratory fitness. Only 19.6% (n = 19) of the examined firefighters were classified as “fit and not obese”, 48.4% (n = 47) were “low fit and not obese” and 30.9% (n = 30) were “low fit and obese”. The results clarify that increasing cardiorespiratory fitness is a fundamental point for the reduction and prevention of cardiovascular complications in firefighters. It could be demonstrated, especially for central risk factors, particularly BMI, waist circumference, sytolic resting blood pressure and triglyceride values. Therefore, firefighters should be motivated to increase their cardiorespiratory fitness for the beneficial effect of decreasing cardiovascular risk profile.

Firefighters Are More Physically Active On-Duty Compared to Off-Duty

Physical inactivity, coupled with increasing obesity levels, in firefighters plays a key role in aggregated cardiovascular events. The purpose of this study was to investigate device-measured physical activity (PA) for firefighters while on- and off-duty to have a clearer understanding of their overall PA level. Methods: Twenty-nine career firefighters participated in this non-experimental, within-subjects study by wearing an accelerometer to assess PA intensities and step-count. Obesity was classified using body mass index (BMI). Dependent t-tests were used to examine mean differences in PA intensities when on- and off-duty. Pearson product-moment correlations were used to assess the association between PA intensities when on and off-duty. Results: According to the World Health Organization BMI categorizations, 20 firefighters were overweight, 9 were obese, and, thus, none were normal weight. Only light PA (LPA) was statistically significant (p = 0.026) for on- and off-duty days with a small-to-medium effect size (d = 0.47), meaning that on average, firefighters performed more minutes of LPA when on-duty compared to off. There was a significant difference between on- (9060.2 ± 2636.4) and off-duty (7495.3 ± 2835.8) daily step counts (p = 0.011). Conclusion: As the results demonstrate, there is a dire need for increased PA levels in firefighters while on- and off-duty.

Relationship between Firefighter Physical Fitness and Special Ability Performance: Predictive Research Based on Machine Learning Algorithms

Firefighters require a high level of physical fitness to meet the demands of their job. The correlations and contributions of individual physical health parameters to the tasks of firefighting would enable firefighters to focus on the effects of specific physical conditions during their physical training programs. Therefore, the purpose of the present study was to identify the relationships between various physical health parameters (weight, maximum oxygen uptake, body fat percentage, upper body muscular power and lower body muscular power) and performance on simulated firefighting ability tasks, which included a set of seven tasks (rope climb, run 200 m round trip with load, 60 m carrying a ladder, climb stairs with load, evacuation of 400 m with supplies, run 5 km with an air respirator, run 100 m with the water hose). Through use of a partial least-squares regression (PLSR) algorithm to analyze the linear correlation, we revealed the change in various training performances of specific ability tests with physical fitness parameters. The present study demonstrated significant relationships among physical health parameters and performance on simulated firefighting ability tasks, which also represent that those parameters contributed significantly to the model’s predictive power and were suitable predictors of the simulated firefighting tasks score.

What do Firefighting Ability Tests Tell Us About Firefighter Physical Fitness? A Systematic Review of the Current Evidence

Fyock-Martin, MB, Erickson, EK, Hautz, AH, Sell, KM, Turnbaugh, BL, Caswell, SV, and Martin, JR. What do firefighting ability tests tell us about firefighter physical fitness? A systematic review of the current evidence. J Strength Cond Res 34(7): 2093-2103, 2020-The firefighting profession is a physiologically demanding occupation. Currently, sudden cardiac deaths account for 40-50% of firefighter job-related deaths, for which, inadequate aerobic fitness (AF) and obesity are established as risk factors. Departments have instituted firefighting physical ability tests (FPATs) as a method of quantifying readiness for occupational-related demands. A systematic review of the current literature examining the correlation between field fitness test performance and FPAT completion times was performed. The search identified 5 studies that met the eligibility criteria. The total number of subjects in the 5 studies was 265 (259 men and 6 women), including 200 professional firefighters (75.5%), 40 volunteer (15.1%), 20 officers (7.5%), and 5 recruits (1.9%). Upper-body strength (UBs) and upper-body endurance (UBe) had the strongest correlation to FPATs (r = -0.31 to -0.66; R = 0.10 to 0.44 and r = -0.27 to -0.61; R = 0.07 to 0.37; p < 0.05, respectively). Two studies suggested that AF has a weak-to-moderate relationship with FPATs (r = 0.38 and r = -0.62). Two studies showed that anaerobic capacity had weak-to-strong correlations with FPATs (r = -0.40 and r = 0.79; R = 0.16 to 0.62; p < 0.05). No studies found a statistically significant correlation between lower-body strength and FPAT performance. Further research is needed to better understand the role of field-based fitness test results on FPAT performance. An annual department-driven multicomponent fitness assessment measuring UBs, UBe, anaerobic capacity, and AF is recommended based on the evidence reviewed.

Efficacy of a Goal Setting and Implementation Planning Intervention on Firefighters' Cardiorespiratory Fitness

Bycura, DK, Dmitrieva, NO, Santos, AC, Waugh, KL, and Ritchey, KM. Efficacy of a Goal Setting and Implementation Planning Intervention on Firefighters' Cardiorespiratory Fitness. J Strength Cond Res 33(11): 3151-3161, 2019-The purpose of this study was to assess the effectiveness of a goal setting and implementation planning (GSIP) intervention on cardiorespiratory fitness among firefighters. Male career firefighters (N = 20) from a large municipal fire department were assigned to an intervention arm (n = 12) or passive control arm (n = 8) of a 14-week study involving cardiorespiratory exercise. The intervention consisted of GSIP coaching at baseline and support throughout the study. Cardiorespiratory fitness was assessed through a standardized physical protocol for firefighters (Candidate Physical Ability Test) at baseline, at 6 weeks, and at 14 weeks time points, using the Cosmed K4b portable metabolic system to measure physiological variables. Using intention-to-treat principles, we employed a 2-level multilevel model to examine the effect of intervention group on intercept and change over time on primary outcomes of interest: oxygen transport and utilization (VO2), heart rate (HR), and respiratory exchange ratio (R). Results demonstrated that the intervention and control groups both exhibited a significant increase in VO2 (B = 0.143, SE = 0.025, p < 0.001) and a decline in R (B = -0.003. SE = 0.001, p < 0.01) over the course of the study. Although both groups exhibited improvements on 2 of the 3 cardiorespiratory outcomes, subjects assigned to the intervention did not exhibit superior outcomes when compared to the control group. Given the improvements we observed in 2 out of 3 outcomes across both conditions, future research may consider testing effectiveness of interventions consisting of functional training exercises that closely translate to firefighting tasks over time periods sufficient to elicit aerobic metabolic adaptations.

Occupationally Tailored, Web-Based, Nutrition and Physical Activity Program for Firefighters: Cluster Randomized Trial and Weight Outcome

OBJECTIVE

The aim of this study was to determine the efficacy of an occupationally tailored, web-based health and wellness program, The First Twenty® (TF20), for weight change among volunteer firefighters.

METHODS

The impact of TF20 on firefighters' 6-month weight change was tested in a cluster, randomized controlled trial, using a crossover design of firefighters in 10 departments. TF20 has web-based nutrition, physical activity, and behavioral health components.

RESULTS

An adjusted treatment-induced weight loss from 1.7 to 2.8 lb was observed for all participants and 2.3 to 3.1 lb among overweight and obese participants. An average weight gain was observed among firefighters in the control condition and weight loss for those in the treatment condition.

CONCLUSIONS

TF20 supports firefighters' weight loss. Firefighters need wellness interventions to improve nutrition and physical activity given their high prevalence of obesity.

The influence of cardiometabolic risk factors on cardiorespiratory fitness in volunteer Chilean firefighters

OBJECTIVES

Maximum oxygen consumption (VO2_max ) plays a fundamental role in firefighters' occupational activities due to the high intensity tasks they perform in their professional duties. In Chile, firefighters are volunteers (non-salary) and their lack of continuous and programmed physical activity may affect their physical fitness and health. The goal of this study was to determine the influence of anthropometric parameters and cardiometabolic risk (CMR) factors on the cardiorespiratory fitness (CRF) of volunteer Chilean firefighters.

METHODS

Seventy-six volunteer male firefighters (median [5-95 percentiles]) aged 27.5 years [26-56], body mass index (BMI) 27.7 kg m^-2 [19.9-35], and VO2_max 44 mL kg^-1 min^-1 [36-56]) participated in the study. The following variables were assessed: BMI, fat mass%, body density, waist circumference (WC), waist-to-hip ratio (WHR), blood pressure, blood glucose, and VO2_max .

RESULTS

In total, 68% of the samples were overweight or obese. A total of 36% presented abdominal obesity (WC ≥102 cm). High blood pressure (HBP) was observed in 25% of firefighters and high blood glucose was found in about 20%. The presence of abdominal obesity was the strongest predictor of VO2_max (OR = 12.35, 95% CI = 3.56-42.82, P < .001), followed by the WHR (OR = 11.5, 95% CI = 3.1-42.7, P < .001) and high blood glucose (OR = 2.87, 95% CI = 1.7-7.3, P = 0.019).

CONCLUSION

This study showed that abdominal obesity in firefighters was the strongest predictor of low CRF. In addition, CRF was associated with CMR factors, except for HBP.

An Occupational-Specific O2max Protocol for Structural Firefighters

OBJECTIVE

The aim of this study was to validate a (Equation is included in full-text article.)O2max protocol designed specifically for the occupational demands of firefighters by incorporating the use of personal protective equipment (PPE).

METHODS

Career firefighters completed a stage-graded exercise test (GXT) with submaximal square-wave verification bout while wearing PPE (pants and boots) to determine (Equation is included in full-text article.)O2max. Using the self-reported Physical Activity-Rating (PA-R) scale and an estimated nonexercise regression equation of (Equation is included in full-text article.)O2max for comparison to measured.

RESULTS

Twenty-eight male, career firefighters performed the GXT and square-wave bout. (Equation is included in full-text article.)O2 values (mean ± SD) from the GXT and the square-wave verification bout were 41.04 ± 6.98 and 39.74 ± 6.42 mL/kg/min, respectively (ICC = 0.98, typical error = 0.96 mL/kg/min, CV = 2.4%).

CONCLUSION

Our data suggest an incremental treadmill protocol that incorporates PPE and square-wave verification as an occupational-specific tool to measure cardiovascular fitness in firefighters.

Pathoanatomic Findings Associated With Duty-Related Cardiac Death in US Firefighters: A Case-Control Study

Background Sudden cardiac death accounts for the greatest proportion of duty-related deaths among US firefighters. Increased understanding of the pathoanatomic causes of sudden cardiac death and the risk associated with underlying cardiac pathologies is needed to develop evidence-based screening recommendations. Methods and Results Using autopsy data for duty-related firefighter fatalities occurring between 1999 and 2014, this retrospective case-control study compared cardiac findings of male firefighters aged 18 to 65 years who died on duty of cardiac-related causes with those who died of noncardiac trauma-related causes. Data from 276 cardiac cases and 351 noncardiac trauma controls were analyzed. Among cardiac cases, the most prevalent (82%) underlying pathoanatomic substrate was comorbid coronary heart disease and cardiomegaly/left ventricular hypertrophy. Cardiac cases had a higher prevalence of cardiomegaly (heart weight >450 g), left ventricular hypertrophy (left ventricular wall thickness ≥1.2 cm), and severe coronary artery stenosis (≥75%) than trauma controls (all P<0.001). In multivariate analyses, heart weight >450 g, coronary artery stenosis ≥75%, and evidence of a prior myocardial infarction were strong independent predictors of cardiac death, with odds ratios of 6.1 (95% confidence interval, 3.6-10.4), 9.3 (95% confidence interval, 5.3-16.1), and 6.2 (95% confidence interval, 3.4-11.3), respectively. Conclusions The majority of cardiac fatalities had evidence of both coronary heart disease and increased heart mass, and each condition was independently associated with a markedly elevated risk of cardiac death. Targeted screening for coronary heart disease, increased heart mass, and evidence of prior myocardial infarction should be considered to reduce duty-related cardiac deaths among firefighters.

Physical Employment Standards for UK Firefighters: Minimum Muscular Strength and Endurance Requirements

Objective:

The aim of this study was to assess sensitivity and specificity of surrogate physical ability tests as predictors of criterion firefighting task performance and to identify corresponding minimum muscular strength and endurance standards.

Methods:

Fifty-one (26 male; 25 female) participants completed three criterion tasks (ladder lift, ladder lower, ladder extension) and three corresponding surrogate tests [one-repetition maximum (1RM) seated shoulder press; 1RM seated rope pull-down; repeated 28 kg seated rope pull-down]. Surrogate test standards were calculated that best identified individuals who passed (sensitivity; true positives) and failed (specificity; true negatives) criterion tasks.

Results:

Best sensitivity/specificity achieved were 1.00/1.00 for a 35 kg seated shoulder press, 0.79/0.92 for a 60 kg rope pull-down, and 0.83/0.93 for 23 repetitions of the 28 kg rope pull-down.

Conclusions:

These standards represent performance on surrogate tests commensurate with minimum acceptable performance of essential strength-based occupational tasks in UK firefighters.

Effect of Body Mass Index on Left Ventricular Mass in Career Male Firefighters

Left ventricular (LV) mass is a strong predictor of cardiovascular disease (CVD) events; increased LV mass is common among US firefighters and plays a major role in firefighter sudden cardiac death. We aim to identify significant predictors of LV mass among firefighters. Cross-sectional study of 400 career male firefighters selected by an enriched randomization strategy. Weighted analyses were performed based on the total number of risk factors per subject with inverse probability weighting. LV mass was assessed by echocardiography (ECHO) and cardiac magnetic resonance, and normalized (indexed) for height. CVD risk parameters included vital signs at rest, body mass index (BMI)–defined obesity, obstructive sleep apnea risk, low cardiorespiratory fitness, and physical activity. Linear regression models were performed. In multivariate analyses, BMI was the only consistent significant independent predictor of LV mass indexes (all, p <0.001). A 1-unit decrease in BMI was associated with 1-unit (g/m^1.7) reduction of LV mass/height^1.7 after adjustment for age, obstructive sleep apnea risk, and cardiorespiratory fitness. In conclusion, after height-indexing ECHO-measured and cardiac magnetic resonance–measured LV mass, BMI was found to be a major driver of LV mass among firefighters. Our findings taken together with previous research suggest that reducing obesity will improve CVD risk profiles and decrease on-duty CVD and sudden cardiac death events in the fire service. Our results may also support targeted noninvasive screening for LV hypertrophy with ECHO among obese firefighters.

Relationship of aerobic fitness with cardiovascular risk factors in firefighters

BACKGROUND

Epidemiological studies on the general population have shown that increased physical activity and aerobic fitness (AF) significantly decrease the risk of coronary artery disease. Finding ways to decrease such risk factors can promote the health of firefighters.

METHODS

This study was conducted in a large industrial facility in Tehran. AF assessment and submaximal aerobic fitness testing of participants were performed according to the guidelines of the American College of Sports Medicine (ACSM). AF was determined using a bicycle ergometer. Other information was collected using a specifically designed questionnaire, physical examination and blood test. Data were analyzed using SPSS. Level of significance was set at P < 0.05.

RESULTS

A total of 157 male firefighters were evaluated in an industrial facility. The results of logistic regression analysis revealed that AF was significantly correlated with age, body mass index (BMI), cigarette smoking, physical activity, hemoglobin level, low-density lipoprotein (LDL) level, high-density lipoprotein (HDL) level, resting systolic blood pressure (RSBP), diastolic blood pressure (RDBP) and heart rate (RHR) (P < 0.05).

CONCLUSIONS

Firefighters with greater AF had lower cardiovascular disease (CVD) risk factors. Longitudinal studies are required to further confirm this finding. Increasing the AF may decrease CVD risk factors in firefighters.

The effect of a novel tactical training program on physical fitness and occupational performance in firefighters

Structural firefighting is a dangerous and physically demanding profession. Thus, it is critical that firefighters exercise regularly to maintain optimal physical fitness levels. However, little is known about optimal training methods for firefighters, and exercise equipment is often not available to on-duty firefighters. Therefore, the purpose of this study was to determine the effect of a novel supervised on-duty physical training program on the physical fitness and occupational performance of structural firefighters. Twenty professional male firefighters were divided into a supervised exercise group (SEG; n = 11) and a control group (CG; n = 9). The SEG participated in a 12-week circuit training intervention. The SEG exercised for 1 hour on 2 d·wk. At baseline and after the intervention, subjects performed a battery of physical fitness tests and a simulated fire ground test (SFGT). At baseline, there were no significant differences (p = 0.822) in the completion rate of the SFGT in the SEG (82%) vs. the CG (78%). After the intervention, a significantly greater proportion of the firefighters in the SEG completed the SFGT compared with the CG (SEG = 100% vs. CG = 56%; p < 0.013). In addition, the SEG demonstrated significant improvements in body mass, fat mass, and body mass index (p ≤ 0.05). The findings of this study indicate that training with firefighter equipment improved occupational performance and anthropometric outcomes in incumbent firefighters. Furthermore, implementing a supervised exercise program using firefighter equipment can be done so in a safe and feasible manner.

Physical fitness profile of professional Italian firefighters: differences among age groups

Firefighters perform many tasks which require a high level of fitness and their personal safety may be compromised by the physiological aging process. The aim of the study was to evaluate strength (bench-press), power (countermovement jump), sprint (20 m) and endurance (with and without Self Contained Breathing Apparatus - S.C.B.A.) of 161 Italian firefighters recruits in relation to age groups (<25 yr; 26-30 yr; 31-35 yr; 36-40 yr; 41-42 yr). Descriptive statistics and an ANOVA were calculated to provide the physical fitness profile for each parameter and to assess differences (p < 0.05) among age groups. Anthropometric values showed an age-effect for height and BMI, while performances values showed statistical differences for strength, power, sprint tests and endurance test with S.C.B.A. Wearing the S.C.B.A., 14% of all recruits failed to complete the endurance test. We propose that the firefighters should participate in an assessment of work capacity and specific fitness programs aimed to maintain an optimal fitness level for all ages.