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Physical Fitness Evaluation of Career Urban and Wildland Firefighters
Abstract
Objective:
Examine the physical fitness of career firefighters and compare their results to normative data and suggested standards for their profession.
Methods:
Eighty firefighters completed a body composition analysis, maximal aerobic capacity (VO2max) test, and fitness testing battery, with results compared with normative value tables. Maximal aerobic capacity was correlated to fitness measures and differences between VO2max quartiles were examined.
Results:
Twenty-two firefighters met the suggested standard for VO2max. Seventy percent of participants were classified as overweight or obese based on body mass index, while 25% were classified as having either "poor" or "very poor" body fat levels. Firefighters were above average for muscular strength.
Conclusion:
The firefighters had low aerobic fitness and higher than optimal body fat levels. Training programs may be necessary to assist firefighters in achieving optimal fitness levels.
... Hauschild et al. [25], in a systematic review of correlations between fitness tests and discrete occupational tasks amongst 27 different studies within the tactical athlete population (13 military population; 10 FF, law enforcement, or peace officer; and 4 healthy civilian populations), found that HG dynamometry test was strongly correlated (r ≥ 0.5) with one-quarter (i.e., lift and lower [single] task with r = 0.67, p < 0.05; lift and lower [repeated] task with r = 0.59, p < 0.05; stretcher carry task with r = 0.61, p < 0.05) of the 12 occupational tasks categories by which the authors examined relationships with it. However, the mean maximal HG strength in studies of FFs' work capacity range from 47 to 61 kg for men, showing that the maximal HG strength in our current research study (33.1 kg ± 7.8 kg) does not fall within norms of previous research studies [32,40,52,[59][60][61][62][63][64][65][66][67][68][69][70]. Such discrepancy may be explained by the fact that, in our protocol, FFs wore their full occupational firefighting gear including their tactical gloves, while the prior research studies either did not use PPE, used parts of it, or did not use a control trial. ...
... Stair climbing protocols have been used amongst researchers to assess anaerobic performance in various tactical athlete populations, including FFs [24,32,61,[71][72][73]. Clarke [24] introduced a tower climb test (TCT) to assess anaerobic performance in urban FFs and found that staircase protocols provided an occupationally specific mean by which to measure anaerobic performance. ...
... p < 0.05). Houck et al. [61] are the only researchers, to our knowledge, having incorporated the MK staircase test, a valid and reliable standardized staircase protocol amongst the tactical athlete populations, specifically on FFs. Their research study examined the physical fitness of 77 wildland FFs from the New Mexico Fire Department and compared their results to ACSM normative data and suggested standards for their profession. ...
... Looking at firefighters, Houck et al. [32] conducted a cross-sectional study on physical fitness in 80 (76 men, 4 women) active-duty urban or wildland firefighters in New Mexico. Data were collected as part of the firefighters' annual health assessment required by their employer. ...
... Results from the military study also indicated that being underweight was protective against hypertension and dyslipidemia [31]. Similarly, for diabetes, research indicated that a higher BMI was associated with an increased risk of T2DM [32]. ...
... One study conducted in law enforcement officers found no significant differences in performance variables between healthy and overweight subjects [33]. Studies conducted in firefighters indicated that an increase in BMI was associated with a decrease in VO 2max , poorer back and core muscular endurance, moderately positively and weakly positively associated with pull-up 1RM and bench press 1RM, and an increased risk of job disability [32][33][34][35]. Three studies in military personnel indicated that a higher BMI was associated with poorer performance [36,37,41], whereas other studies indicated that a higher BMI was positively associated with muscular strength and power, but negatively associated with speed/agility [39,40]. ...
The prevalence of overweight and obesity among tactical populations is estimated at 70-75%, which may negatively impact health and performance. The relationship between body mass index (BMI) and health and performance is well established among the general population, however literature on such relationships among tactical populations has yet to be reviewed and evaluated. The purpose of this study was to systematically review available literature on the relationship between BMI and health and occupational performance among law enforcement officers (LEO), firefighters, and military personnel. After reviewing the literature, 27 articles were included. Nine studies found BMI was positively associated with cardiovascular disease (CVD) risk factors. Studies involving BMI and cancer were lacking. One study found BMI was positively associated with type 2 diabetes (T2DM) risk. Five studies on occupational/physical performance and twelve studies on injury found a higher BMI was often indicative of decreased performance and increased risk of injury in general, but protective against stress fractures. Overall, higher BMI was often associated with negative health and performance outcomes among tactical populations, especially when beyond the overweight classification. Public health practitioners should focus efforts on improving nutrition and physical activity to promote a healthy BMI among these individuals.
... Hauschild et al. [25], in a systematic review of correlations between fitness tests and discrete occupational tasks amongst 27 different studies within the tactical athlete population (13 military population; 10 FF, law enforcement, or peace officer; and 4 healthy civilian populations), found that HG dynamometry test was strongly correlated (r ≥ 0.5) with one-quarter (i.e., lift and lower [single] task with r = 0.67, p < 0.05; lift and lower [repeated] task with r = 0.59, p < 0.05; stretcher carry task with r = 0.61, p < 0.05) of the 12 occupational tasks categories by which the authors examined relationships with it. However, the mean maximal HG strength in studies of FFs' work capacity range from 47 to 61 kg for men, showing that the maximal HG strength in our current research study (33.1 kg ± 7.8 kg) does not fall within norms of previous research studies [32,40,52,[59][60][61][62][63][64][65][66][67][68][69][70]. Such discrepancy may be explained by the fact that, in our protocol, FFs wore their full occupational firefighting gear including their tactical gloves, while the prior research studies either did not use PPE, used parts of it, or did not use a control trial. ...
... Stair climbing protocols have been used amongst researchers to assess anaerobic performance in various tactical athlete populations, including FFs [24,32,61,[71][72][73]. Clarke [24] introduced a tower climb test (TCT) to assess anaerobic performance in urban FFs and found that staircase protocols provided an occupationally specific mean by which to measure anaerobic performance. ...
... p < 0.05). Houck et al. [61] are the only researchers, to our knowledge, having incorporated the MK staircase test, a valid and reliable standardized staircase protocol amongst the tactical athlete populations, specifically on FFs. Their research study examined the physical fitness of 77 wildland FFs from the New Mexico Fire Department and compared their results to ACSM normative data and suggested standards for their profession. ...
Physical ability test (PAT) evaluates firefighters’ (FF) occupational capacity. The contribution of anaerobic systems during PAT and mental toughness (MT) relationship to PAT is unexplored. PAT modeling based on anaerobic fitness (AF), MT, and respective relationships were examined. Fourteen male FFs (Age: 29.0 ± 7.0 years) completed a PAT composed of occupationally-specific tasks in full gear. On a separate day, a series of AF assessments were performed (handgrip-dynamometry: HG; vertical-jump: VJ; Margaria-Kalamen: MK; 300-yard shuttle run: 300YD). MT was evaluated using military training MT inventory (MTMTI) and sports MT questionnaire (SMTQ). We tested the PAT model using multiple backward regression and related correlations coefficients at p < 0.05. A 78% proportion of PAT was explained by AF parameters (F2,13 = 20.2, <0.05). PAT was significantly correlated with HG (r = −0.71, p < 0.01), VJ (r = −0.73, p < 0.01), MK (r = −0.75, p < 0.01), and with 300YD (r = 0.60, p < 0.05). MT did not demonstrate significant correlation with PAT (p > 0.01). Anaerobic system significantly contributes to PAT performance. FFs should optimize AF training, which would allow for enhanced occupational performance in PAT. Further investigation into psychological determinants of FFs is recommended.
... Tasks involving quick bursts of energy production without lactate as a by-product represent the alactic state. Examples include handgrip dynamometry [5,9,[14][15][16] and vertical jump [1,6,8,9,14,[17][18][19]. Conversely, tasks like the Margaria-Kalamen (MK) [14,17] and the 300-yard shuttle run [14,20] mainly indicate the lactate state. ...
... Examples include handgrip dynamometry [5,9,[14][15][16] and vertical jump [1,6,8,9,14,[17][18][19]. Conversely, tasks like the Margaria-Kalamen (MK) [14,17] and the 300-yard shuttle run [14,20] mainly indicate the lactate state. These tests collectively assess AF, providing crucial insights into firefighters' readiness for the physical demands of their occupation. ...
Background
Personal protective equipment (PPE) is vital for firefighters’ safety and effectiveness during daily operations. However, concerns have emerged about its potential impact on firefighters’ anaerobic fitness (AF), which is crucial for their operational readiness. The Physical Ability Test (PAT) is used to assess readiness, but there is inconsistency among fire departments regarding whether PAT is conducted with full PPE or regular exercise clothing. This variation in testing conditions may exacerbate the stress on firefighters’ AF.
Aims
To analyse differences in firefighters’ AF performance while wearing full PPE compared to regular exercise clothing.
Methods
We studied two cohorts totalling 62 firefighters from specific fire departments in South Florida. We conducted occupation-specific AF tests, including handgrip dynamometry (HG), vertical jump (VJ), Margaria–Kalamen (MK), and a 300-yard shuttle run (300YD), both with full PPE (WPPE) and without PPE (NPPE). We adjusted AF variables for body weight (e.g. NPPE) and occupational weight (e.g. WPPE) and used a repeated-measures design in Jamovi (P < 0.05).
Results
Wearing WPPE significantly reduced relative HG strength by 59%, VJ peak power by 11%, and MK mean power by 49%, while increased 300YD completion time by 18%.
Conclusions
The study reveals that PPE substantially impairs firefighters’ anaerobic performance during occupation-specific tests. This emphasizes the need for tailored AF training programs to support the anaerobic system and related performance while wearing PPE, acknowledging the significance of occupational specificity in assessing firefighters’ fitness components.
... There was a significantly moderate negative correlation between obesity and cardiorespiratory fitness (R = −0.595, p < 0.001) [49,72,73,75,76,84,86] with substantial heterogeneity (I 2 = 77%) among the studies. In subgroup analysis, there was no heterogeneity between studies using a cycle ergometer for testing (I 2 = 0%). ...
... There was a significantly moderate negative correlation between body-fat percentage and cardiorespiratory fitness (R = −0.663, p < 0.001) [72,73,76,84], moderate heterogeneity (I 2 = 55%) among the studies, and no indication of publication bias (Egger's test p = 0.455). Heterogeneity was reduced (I 2 = 27%) following subgroup analysis on testing procedures that used a cycle ergometer. ...
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.
... However, the average VO 2peak in this cohort was 32.8 mL O 2 /kg/min, which is similar to previous reports in career firefighters (Houck et al., 2020) but less than the 42 mL O 2 /kg/min recommended by the NFPA (National Fire Protection Association, 2022). Therefore, improving the physical capacity of firefighters should be a point of focus among fire administrators. ...
Background
Alcohol misuse is prevalent among firefighters, and associated adverse cardiometabolic health consequences could negatively impact readiness for duty. Mental health conditions may confer additional risk. Therefore, we aimed to determine whether alcohol misuse increases cardiometabolic risk among firefighters and whether mental health conditions modify these relationships.
Methods
Deidentified data from firefighters (N = 2405; 95.8% males, 38 ± 9 years, 29.6 ± 4.6 kg/m²) included demographics, Alcohol Use Disorders Identification Test (AUDIT) and AUDIT‐C scores, mental health screening scores, anthropometrics, metabolic panel, and cardiorespiratory testing results. Differences in cardiometabolic parameters between firefighters with low AUDIT‐C (<3 [females] or <4 [males]; no or low‐risk alcohol use) or high AUDIT‐C (≥3 [females] or ≥4 [males]; hazardous alcohol use) were determined and odds ratios for clinical risk factors were calculated. Posttraumatic stress disorder (PTSD), insomnia, depression, and anxiety were assessed as moderators.
Results
Firefighters with high AUDIT‐C had significantly (p < 0.05) higher total cholesterol (TC), high‐density lipoprotein (HDL‐C), and systolic blood pressure (SBP) and diastolic blood pressure (DBP) and lower hemoglobin A1C (HbA1c) than those with low AUDIT‐C. In unadjusted and/or adjusted analyses, those with high AUDIT‐C had increased risk for overweight/obesity, hypercholesterolemia, and prehypertension/hypertension, and decreased risk for low HDL and elevated HbA1c. There were inverse moderation effects by posttraumatic stress disorder (PTSD), depression, and anxiety on relationships between AUDIT‐C score and BP. Insomnia (directly) and anxiety (inversely) moderated relationships between AUDIT‐C score and circulating lipids.
Conclusions
Firefighters with high AUDIT‐C have differential cardiometabolic risk, with specific relationships altered by mental health status. Whether higher HDL and lower HbA1c with high AUDIT‐C in firefighters is protective long‐term remains to be explored. Overall, these results underscore the need for alcohol screening and intervention to maintain cardiometabolic health and long‐term occupational readiness among firefighters.
... Regarding the results of the correlation among the physical fitness, stress, and sleep quality variables, the body composition variables were the most associated with the other fitness variables, both positively and negatively. The systematic review analyzing the tactical population (firefighters, police, and military) by Sergi et al. (2023) corroborates this information: increased BMI associated with decreased VO2 max (Houck et al., 2020), lower muscular resistance (Maglione et al., 2022), greater muscular strength and power, but negatively associated with speed and agility (Rtibale et al., 2010). ...
The objective of the study was to predict the level of stress in military submariners based on physical fitness and sleep quality variables. Cross-sectional and correlational research, with a sample of 40 male submariners (28.70±3.98 years old). Body mass and composition data were analyzed (MCT), height, BMI, waist, body fat (%G), dominant handgrip (PMDom), cardiorespiratory fitness (VO2max), squats, sit-ups, relative power of lower limbs (PotRel MMII), stress (PSS-10), Epworth Sleepiness Assessment (ESE) and Pittsburgh Sleep Quality Index (PSQI). Overall, negative associations (p<0.05) were observed between VO2max and MCT, BMI, %BF, and waist; PotRel MMII and age and %BF; squat and %G; sit-up and MCT, BMI, %BF and waist; and finally, stress and VO2max and sit-up. Furthermore, positive associations (p<0.05) between BMI and MCT; %BF and MCT and BMI; waist and age, BMI, MCT, and %BF; squats and PMdom., VO2max and PotRel MMII; sit-ups and VO2max, PotRel LL and squats; ending with PSQI and stress. Furthermore, among the stress level prediction equation models developed, the equation Stress=15.92+1.538(PSQI)-0.497(VO2max)+0.188(Squat) met the proposed requirements, which is based on sleep quality, cardiorespiratory fitness, and number of squats. Keywords: Submariner; stress, physical fitness, sleep quality, military personal.
... The 20-29 age group scored 2% above the ACSM guidelines, the 30-39 age group scored 4% above and the 40+ age group scored 12% above the YMCA bench press norms for the general population. Our findings were similar to those in the previous literature exploring other tactical populations, such as firefighters, who maintained similar scores in the "well above average" and "above average" categories with a mean score of 43.8 repetitions [38], and a previous study assessing firefighters with a mean score of 30.4 repetitions [39]. Notably, a considerable decline in strength relative to the general population's normative values was observed with increasing officer age. ...
Physical fitness is mandatory for public safety officers. Police officers experience elevated levels of cardiovascular disease and associated risks making fitness a peak concern. Officers often have more marked fitness level decreases with aging compared to the general population. This cross-sectional study investigated the cardiovascular health, muscular strength/endurance, and mobility of officers in a medium-sized police department (N = 83); (4 females, 79 males), age (36.82 ± 10 years), height (179.02 ± 7.7 cm), body mass (95.1 ± 16.29 kg) compared to American College of Sports Medicine (ACSM) guidelines. The findings revealed that police officers begin their careers with above average strength but demonstrate greater declines with age than the general population. Officers also demonstrated cardiovascular fitness below ACSM standards and significant decreases with aging compared to the general population. Body fat percentages (p = 0.003) and BMI (p = 0.028) surpassed recommendations, with higher than normal increases with age. Maximum vertical jump decreased as officers age (p = 0.004). These findings support the implementation of a targeted physical fitness regimen and the resources for a program designed to improve current health and fitness, reduce the greater than expected decreases with aging, and aim to optimize occupational performance and the safeguarding of the lifelong health and well-being of officers.
... The average strength characteristics of WLFFs have remained a relatively understudied topic. A recent foundational study did, however, examine the muscle strength characteristics of a combined group of active-duty urban firefighters and WLFFs (76 males, 4 females) (58). While the mean age of each subgroup from this study was older (35 ± 8 years) than other WLFF studies referenced herein (109,120), these data demonstrated that the majority of participants achieved a score of "excellent" or "good" on the YMCA bench press test (44 ± 17 repetitions, males 36 kg, females 16 kg barbell, metronome at 60 beats/min). ...
Wildland firefighters (WLFFs) are inserted as the front-line defense to minimize loss of natural resources, property, and human life when fires erupt in forested regions of the world. The WLFF occupation is physically demanding as exemplified by total daily energy expenditures that can exceed 25 MJ/day (6000 calories). WLFFs must also cope with complex physical and environmental situations (i.e., heat, altitude, smoke, compromised sleep, elevated stress) which challenge thermoregulatory responses, impair recovery, and increase short- and long-term injury/health risks while presenting logistical obstacles to nutrient and fluid replenishment. The occupation also imposes emotional strain on both the firefighter and their families. The long-term implications of wildfire management and suppression on the physical and mental health of WLFFs are significant, as the frequency and intensity of wildland fire outbreaks as well as the duration of the fire season is lengthening and expected to continue to expand over the next three decades. This article details the physical demands and emerging health concerns facing WLFFs, in addition to the challenges that the U.S. Forest Service and other international agencies must address to protect the health and performance of WLFFs and their ability to endure the strain of an increasingly dangerous work environment. © 2023 American Physiological Society. Compr Physiol 13:4587-4615, 2023.
... To work without restrictions, they must maintain an aerobic capacity of at least eight METs. In comparison, the maximal oxygen consumption (VO2 max) standard proposed by the NFPA was passed by 51.0% of Colorado firefighters [23] and 27.5% of New Mexico wildland firefighters [24], which showed a higher proportion than this study. However, both studies were conducted with firefighters at a younger age. ...
Wildland firefighting is a high-risk occupation. The level of cardiopulmonary fitness can indicate whether wildland firefighters are ready to perform their job duties. This study’s objective was to determine wildland firefighters’ cardiopulmonary fitness using practical methods. This cross-sectional descriptive study aimed to enroll all 610 active wildland firefighters in Chiang Mai. The participants’ cardiopulmonary fitness was assessed using an EKG, a chest X-ray, a spirometry test, a global physical activity questionnaire, and the Thai score-based cardiovascular risk assessment. The NFPA 1582 was used to determine “fitness” and “job restriction”. Fisher’s exact and Wilcoxon rank-sum tests were used to compare cardiopulmonary parameters. With a response rate of 10.16%, only eight wildland firefighters met the cardiopulmonary fitness requirements. Eighty-seven percent of participants were in the job-restriction group. An aerobic threshold of eight METs, an abnormal EKG, an intermediate CV risk, and an abnormal CXR were the causes of restriction. The job-restriction group had a higher 10-year CV risk and higher systolic blood pressure, although these differences were not statistically significant. The wildland firefighters were unfit for their task requirements and were more at risk of cardiovascular health compared to the estimated risk of the general Thai population. To improve the health and safety of wildland firefighters, pre-placement exams and health surveillance are urgently needed.
... The results in the current study indicated that 47.2% of firefighters did not meet the minimum requirement of 42 mL·kg·min for firefighting, as recommended by many researchers. A study by Houck et al. [54] reported that only 27.5% of full-time Urban and Wildland firefighters from New Mexico met the minimum recommended cardiorespiratory fitness level, substantially lower than the current pilot study. Comparably, Baur et al. [55] reported that 56.3% career firefighters in the United States did not meet the minimum recommendation of 42 mL·min·kg. ...
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.
... Participants reported that they were physically active by meeting the minimum guidelines for exercise participation according to the American College of Sports Medicine, but were below the 80th percentile for VO 2 max based on age and sex (American College of Sports Medicine et al. 2018). These physical fitness criteria were selected to reflect the average fitness of individuals in military, firefighting, and agricultural work (Fallowfield et al. 2019;Houck et al. 2020;Diniz et al. 2020). Participants were not formally heat acclimated and data collection took place between the months of March and May in the Northern Hemisphere with local temperature ranging from 2 °C to 27 °C, so it was unlikely that participants were heat acclimatized due to local environmental temperatures. ...
Purpose
The purpose of this study was to determine the effect of prolonged high-intensity interval (INT) and moderate-intensity continuous (CONT) treadmill exercise in the heat on markers of enterocyte injury and bacterial endotoxin translocation.
Methods
Nine males completed 2 h of work-matched exercise in the heat (40 °C and 15% RH) as either INT (2 min at 80% VO2max and 3 min at 30% VO2max) or CONT (~ 50% of VO2max). Blood samples collected pre- and post-exercise were assayed for intestinal fatty acid-binding protein (I-FABP), claudin-3 (CLDN-3), and lipopolysaccharide-binding protein (LBP).
Results
I-FABP was significantly increased from pre- to post-exercise in CONT (913.96 ± 625.13 to 1477.26 ± 760.99 pg•mL⁻¹; p = 0.014, d = 0.766) and INT (714.59 ± 470.27 to 1547.93 ± 760.99 pg•mL⁻¹; p = 0.001, d = 1.160). Pre- to post-exercise changes in I-FABP were not different between CONT and INT (p = 0.088, d = 0.414). LBP was significantly increased from pre- to post-exercise in INT (15.94 ± 2.90 to 17.35 ± 3.26 μg•mL⁻¹; p = 0.028, d = 0.459) but not CONT (18.11 ± 5.35 to 16.93 ± 5.39 μg•mL⁻¹; p = 0.070, d = 0.226), and pre- to post-exercise changes in LBP were higher in the INT compared to CONT (p < 0.001, d = 1.160). No significant changes were detected from pre- to post-exercise for CLDN-3 in CONT (14.90 ± 2.21 to 15.30 ± 3.07 μg•mL⁻¹) or INT (15.55 ± 1.63 to 16.41 ± 2.11 μg•mL⁻¹) (p > 0.05).
Conclusions
We conclude that prolonged exercise in the heat induces enterocyte injury, but interval (or intermittent) exercise may cause greater bacterial endotoxin translocation which may increase the risk for local and systemic inflammation.
... 28 Body composition, cardiorespiratory fitness, muscular strength and endurance have been reported to decrease throughout their careers and as they age, particularly those that are physically inactive. [29][30][31][32][33][34] Maintenance of good overall levels of health-related physical fitness is crucial for career longevity and overall well-being in firefighters. 2 35 36 In addition, firefighters have been reported to have the highest incidence of musculoskeletal injuries among all emergency services personnel. ...
Introduction: Firefighting is a hazardous occupation, where firefighters are involved in life-threatening situations, being placed under tremendous physical strain, while wearing heavy and insulated equipment to protect them from chemicals, fumes, and high temperatures. This necessitates that firefighter stay in good physical condition and maintain adequate cardiovascular fitness to cope with these stressors and perform their duties with minimal health risks. The aim of this review is to determine the effect of cardiovascular health, musculoskeletal health, and physical fitness on the occupational performance of firefighters.
Methods and analysis: All study types and designs will be included and appraised. The following electronic databases will be searched: PubMed/Medline, SCOPUS, Web of Science, Embase, EBSCOHost, and CINAHL, with no limitations to publication year. The literature search will be conducted comprehensively to enable the capturing of as many relevant articles as possible, but limited to English papers only. A combination of the appropriate terms (search string) will be used to ensure the inclusion of the relevant components of the participants, exposure, comparison and outcome (PECO). A researcher-generated form with the key characteristics of each study will be used to retrieve all relevant details from the selected studies for initial eligibility screening. The Rayyan® intelligent systematic review tool will be used to screen and select studies for inclusion. Thereafter, information from the included studies will be captured on the researcher-generated data extraction form. The Critical Appraisal Skills Programme (CASP) toolkit will be used to conduct the methodological assessment of each study included. Data will be analysed using Review Manager 5.3. Generated results will be presented using a combination of figures, graphs, and tables. The synthesis of quantitative data (using a meta-analysis methodology) will involve the integration of quantitative findings from multiple studies to achieve coherence.
Ethics and Dissemination: This study obtained ethical clearance from the University of the Western Cape Biomedical Research Ethics Committee (BMREC) (BM21/10/9). We will disseminate the findings of the systematic review in peer-reviewed journals and in national and international conferences. In addition, the protocol will form part of a chapter for a doctoral thesis.
Registration: PROSPERO, CRD42021258898
... Additionally, several studies have reported relationships between muscular strength, power, and anaerobic endurance with a firefighter's ability to perform essential occupational tasks such as a victim drag, equipment hoist, ladder carry, stair climbing, and hose deployment [245][246][247]. Thus, high levels of both aerobic and muscular fitness have been recommended for adequate occupational performance for both structural and wildland firefighters [248]. ...
This position stand aims to provide an evidence-based summary of the energy and nutritional demands of tactical athletes to promote optimal health and performance while keeping in mind the unique challenges faced due to work schedules, job demands, and austere environments. After a critical analysis of the literature, the following nutritional guidelines represent the position of the International Society of Sports Nutrition (ISSN).
GENERAL RECOMMENDATIONS Nutritional considerations should include the provision and timing of adequate calories, macronutrients, and fluid to meet daily needs as well as strategic nutritional supplementation to improve physical, cognitive, and occupational performance outcomes; reduce risk of injury, obesity, and cardiometabolic disease; reduce the potential for a fatal mistake; and promote occupational readiness.
MILITARY RECOMMENDATIONS Energy demands should be met by utilizing the Military Dietary Reference Intakes (MDRIs) established and codified in Army Regulation 40-25. Although research is somewhat limited, military personnel may also benefit from caffeine, creatine monohydrate, essential amino acids, protein, omega-3-fatty acids, beta-alanine, and L-tyrosine supplementation, especially during high-stress conditions.
FIRST RESPONDER RECOMMENDATIONS Specific energy needs are unknown and may vary depending on occupation-specific tasks. It is likely the general caloric intake and macronutrient guidelines for recreational athletes or the Acceptable Macronutrient Distribution Ranges for the general healthy adult population may benefit first responders. Strategies such as implementing wellness policies, setting up supportive food environments, encouraging healthier food systems, and using community resources to offer evidence-based nutrition classes are inexpensive and potentially meaningful ways to improve physical activity and diet habits. The following provides a more detailed overview of the literature and recommendations for these populations.
Wildland firefighters (WLFFs) are inserted as the front‐line defense to minimize loss of natural resources, property, and human life when fires erupt in forested regions of the world. The WLFF occupation is physically demanding as exemplified by total daily energy expenditures that can exceed 25 MJ/day (6000 calories). WLFFs must also cope with complex physical and environmental situations (i.e., heat, altitude, smoke, compromised sleep, elevated stress) which challenge thermoregulatory responses, impair recovery, and increase short‐ and long‐term injury/health risks while presenting logistical obstacles to nutrient and fluid replenishment. The occupation also imposes emotional strain on both the firefighter and their families. The long‐term implications of wildfire management and suppression on the physical and mental health of WLFFs are significant, as the frequency and intensity of wildland fire outbreaks as well as the duration of the fire season is lengthening and expected to continue to expand over the next three decades. This article details the physical demands and emerging health concerns facing WLFFs, in addition to the challenges that the U.S. Forest Service and other international agencies must address to protect the health and performance of WLFFs and their ability to endure the strain of an increasingly dangerous work environment. © 2023 American Physiological Society. Compr Physiol 13:4587‐4615, 2023.
A bstract
Background
Cardiorespiratory fitness (CRF) helps physiotherapists in assessing body health and is a strong predictor of cardiovascular morbidity and mortality. Assessment of physical parameters may reveal some insight into factors affecting CRF. This study aimed to assess CRF and factors affecting CRF in young adults.
Materials and Methods
An observational analytical study was conducted on 102 participants from the community of Ahmedabad, Gujarat, India, aged 18–24 years, males and females. Queens College Step Test (QCT) for CRF, body mass index (BMI) for obesity, Sit and Reach Test for flexibility, and Beiring–Sorenson Test for back endurance were performed, and data were analyzed using odds ratio. VO 2max was calculated with McArdle’s equation.
Result
Mean age of 102 participants was (21.02 ± 1.08) years. Mean values for BMI (23.35 ± 4.48) kg/m ² , VO 2max of participants who completed the QCT (42.26 ± 3.08) mL/kg/min, back endurance (78.97 ± 37.95) sec, and flexibility (13.72 ± 3.19) inches were seen. OR for QCT with BMI (3.52, CI: 2.41–5.16), flexibility (0.1, CI: 0.04–0.26), endurance (2.8, CI: 2.01–3.94), and history of coronavirus disease-2019 (2.8, CI: 2.04–4.012) were seen.
Conclusion
The CRF of young adults was found to be low. BMI, flexibility, and back endurance were found to affect CRF in young adults.
The aim of this study is to carry out a comparative analysis of different methodologies for testing the basic and specific physical preparation of firefighters that are applied in different countries of the world and, based on the application of the synthesis of knowledge, to provide a theoretical basis for the optimization and definition of the most adequate model of testing the fire service in the Republic of Serbia. Adequate levels of firefighting skills, physical abilities and energetic mechanisms of energy generation, contribute to reducing the risk of injuries and enable firefighters to resist the overall stress in the profession and to be efficient in specific task realization. Different countries worldwide have different methodologies for testing basic and specific physical preparedness of firefighters. Current testing systems implemented in the USA, Canada, Great Britain, Spain, Sweden and South Korea were analyzed. The analysis found that there is a significant correlation between the values of the basic and specific tests of the physical abilities of firefighters, with the fact that the specific tests are performed in complete personal protection. Based on the synthesis of applied tests and abilities in the analyzed countries, it was established that 24 tests are used to assess basic physical abilities, 14 for specific abilities and 29 for specific physical abilities. In accordance with the established results, it can be concluded that it is necessary to develop specific standardized test procedures for use throughout the fire service in Serbia. In addition to a more efficient assessment of specific physical preparedness, this would also enable control of the state of our firefighters through a more valid comparison of results, which would help in the development of normative data and new methodology needed for more efficient professionalization of the fire service. Established results imply that testing should be conducted biannually with the implementation of specific tests in complete personal protective equipment (PPE) with firefighting equipment. Also, it is necessary to enable adequate testing conditions for firefighters in smaller firefighting units in corresponding testing conditions with equipment.
Background: Firefighting is a strenuous occupation that requires firefighters to be in excellent physical condition. However, some of these professionals are not sufficiently physically fit for duty, negatively impacting their performance. Objective: To cardiopulmonary characterize Portuguese firefighters at different exercise intensities to clarify if their physical fitness profile is adequate to overcome their occupational activities demands. Methodology: Twenty-four healthy Portuguese firefighters performed an intermittent running protocol (with 1 km·h−1 increments and 30 s intervals) on a treadmill. Cardiorespiratory variables and core temperature were measured continuously during the exercise, while blood lactate and rating of perceived exertion were assessed during the rest periods between steps. Results: The increase in velocity along the running protocol resulted in higher values of oxygen uptake (41.5 ± 8.5 mL/min/kg), blood lactate (13.5 ± 4.6 mmol/L) and rating of perceived exertion (19 ± 1). However, there was stabilization of the respiratory quotient and heart rate from heavy to severe intensities. Discussion/Conclusions: Portuguese firefighters have a minimum level of cardiopulmonary fitness to perform their professional duties. However, given the high demands on the cardiopulmonary function of firefighting, it is essential that firefighters participate in regular training programs to maintain and develop cardiopulmonary physical fitness.
Context
Wildland firefighters (WLFFs) are at an increased risk of health conditions, injuries, and illnesses related to sustained levels of intense physical activity. The purpose of this study was to identify and explore the current attitudes and beliefs of WLFFs regarding health services.
Methods
We used consensual qualitative research (CQR) design for this study. Participants engaged in an online, semi-structured interview.
Results
We identified four domains: 1) risk mitigation strategies, 2) culture of fire services, 3) access to healthcare services, and 4) identification of healthcare gap.
Conclusions
Access to occupational health services for WLFFs is readily available in the form of emergency medical care. However, a lack of regular access to physical medicine and the continuation of care beyond acute treatment was apparent.
It is difficult for the traditional physical fitness evaluation methods to dig useful information from massive data, and the accuracy of physical fitness evaluation is low. Therefore, this study proposed a physical fitness evaluation method in the stage of physical exercise behavior based on Bayesian and data mining for the college students. The purpose was to set the association rules of exercise behavior stage, to mine the association mapping relationship in the data set by using frequent itemsets, to build a regression model and to select the best physical variables in the exercise behavior stage. The frequent itemset was used to eliminate the redundancy of physical fitness data, the causal relationship was used to sort the physical exercise behavior stage, and the transformation of physical fitness evaluation index system was realized through Bayesian network topology to realize the physical fitness evaluation in the physical exercise behavior stage. The experimental results showed that the accuracy of this method was as high as 97.62%, and the recall rate of fitness data evaluation was as high as 99.3%. At the same time, the effect of fitness evaluation was better in a short evaluation time.
For firefighters around the world, fire training is necessary to ensure operational readiness, but can be hazardous. Fire instructors routinely attempt to design safe but realistic scenarios and may do so in very different thermal environments. Yet, the physiological burden (and presumed physiological benefits) of different training has rarely been investigated. We studied the impact of three training fire environments: (a) pallets (Pallet), (b) oriented strand board (OSB) and simulated fire/smoke (Fog) on firefighters’ and fire instructors’ physiological responses. Peak ambient temperatures exceeded 420 °C in Pallet and OSB scenarios, but were less than 40 °C for Fog. Firefighters’ peak core temperatures, heart rates and hemostatic responses were not statistically different among the training environments despite the large differences in ambient conditions. Instructors’ heart rate and hemostatic responses were significantly blunted compared to the firefighters’ despite similar peak core temperatures, suggesting instructors performed less work or were less stressed. It is important that physiological responses experienced by firefighters and instructors working in fully encapsulating personal protective equipment be considered based on intensity and duration of work, regardless of the apparent risk from ambient conditions.
Cardiovascular disease (CVD) is the most common cause of job-related mortality among firefighters in the United States. Although age, family history, and work environments cannot be controlled, other predictors are modifiable. If solutions are to be implemented, it is important to know which health parameters are responsible for the elevated CVD risk in this population.
PURPOSE: To examine the cardiovascular health of California firefighters.
METHODS: We measured physiological CVD risk factors in 35 firefighters from Northern California. Assessments were age, anthropometry, blood lipids, blood pressure, and blood glucose. Risk factors were summed according to the American College of Sports Medicine guidelines. We evaluated the frequency of individual risk factors and used regression analyses (logistic, negative binomial, and linear as appropriate) to test the effect of age on risk.
RESULTS: Firefighters were 33.5 ± 11.8 years old, had a body mass index (BMI) of 26.6 ± 3.4, body fat percent (BF%) of 21.2 ± 6.0%, waist circumference (WC) of 90.3 ± 10.4 cm, and waist-hip ratio of 0.87 ± 0.10. Systolic blood pressure (SBP) was 122.5 ± 8.0 mmHg, diastolic pressure (DBP) was 78.1 ± 10.3 mmHg, fasted blood glucose (FBG) was 98.5 ± 14.3 mg/dL, LDLs were 128.9 ± 40.1 mg/dL, HDLs were 31.6 ± 12.5 mg/dL, triglycerides were 116.8 ± 90.3, and the average number of risk factors was 1.8 ± 1.2. There were 32 firefighters (91.4%) with ≥ 1 risk. The proportion of at-risk firefighters for each variable was: lipid profile (77.1%), obesity (65.7%), FBG (37.1%), blood pressure (34.3%), and age (14.3%). Most of the lipid profile was met by low HDLs (65.7% of all firefighters). Age was a significant predictor of BMI (p=0.001), BF% (p=0.003), WC (p=0.001), and waist-hip ratio (p=0.047), but not SBP (p=0.553), DBP (p=0.590), FBG (p=0.961), HDLs (p=0.369), LDLs (p=0.593), or triglycerides (p=0.688). Increased age significantly predicted an increased number of CVD risk factors (p=0.003).
CONCLUSION: As firefighters advanced in age, they experienced elevations in CVD risk, mostly as a consequence of increasing adiposity. Weight loss interventions aimed at improving lipid profile, blood glucose, and blood pressure may help reduce job-related CVD mortality in American firefighters.
The overall aim of this study was to measure the physiological responses of firefighters from a single fire service during simulated functional firefighting tasks and to establish the relationship between physical fitness parameters and task performance. 46 males and 3 females firefighters were recruited. Firefighters’ aerobic capacity levels were estimated using the Modified Canadian Aerobic Fitness Test (mCAFT). Grip strength levels, as a measure of upper body strength levels, were assessed using a calibrated J-Tech dynamometer. The National Institute for Occupational Safety and Health (NIOSH) protocol for the static floor lifting test was used to quantify lower body strength levels. Firefighters then performed two simulated tasks: a hose drag task and a stair climb with a high-rise pack tasks. Pearson’s correlation coefficients (r) were calculated between firefighters’ physical fitness parameters and task completion times. Two separate multivariable enter regression analyses were carried out to determine the predictive abilities of age, sex, muscle strength, and resting heart rate on task completion times. Our results displayed that near maximal heart rates of ≥88% of heart rate maximum were recorded during the two tasks. Correlation (r) ranged from −0.30 to 0.20. For the hose drag task, cardiorespiratory fitness and right grip strength (kg) demonstrated the highest correlations of −0.30 and −0.25, respectively. In predicting hose drag completion times, age and right grip strength scores were shown to be the statistically significant (p
Firefighters’ thermal burden is generally attributed to high heat loads from the fire and metabolic heat generation, which may vary between job assignments and suppression tactic employed. Utilising a full-sized residential structure, firefighters were deployed in six job assignments utilising two attack tactics (1. Water applied from the interior, or 2. Exterior water application before transitioning to the interior). Environmental temperatures decreased after water application, but more rapidly with transitional attack. Local ambient temperatures for inside operation firefighters were higher than other positions (average ~10–30 °C). Rapid elevations in skin temperature were found for all job assignments other than outside command. Neck skin temperatures for inside attack firefighters were ~0.5 °C lower when the transitional tactic was employed. Significantly higher core temperatures were measured for the outside ventilation and overhaul positions than the inside positions (~0.6–0.9 °C). Firefighters working at all fireground positions must be monitored and relieved based on intensity and duration.
Practitioner Summary: Testing was done to characterise the thermal burden experienced by firefighters in different job assignments who responded to controlled residential fires (with typical furnishings) using two tactics. Ambient, skin and core temperatures varied based on job assignment and tactic employed, with rapid elevations in core temperature in many roles.
The aim of this study was to quantify the physical demands of a simulated firefighting circuit and to establish the relationship between job performance and endurance and strength fitness measurements. On four separate days 41 professional firefighters (39 ± 9 yr, 179.6 ± 2.3 cm, 84.4 ± 9.2 kg, BMI 26.1 ± 2.8 kg/m2) performed treadmill testing, fitness testing (strength, balance and flexibility) and a simulated firefighting exercise. The firefighting exercise included ladder climbing (20 m), treadmill walking (200 m), pulling a wire rope hoist (15 times) and crawling an orientation section (50 m). Firefighting performance during the simulated exercise was evaluated by a simple time-strain-air depletion model (TSA) taking the sum of z-transformed parameters of time to finish the exercise, strain in terms of mean heart rate, and air depletion from the breathing apparatus. Multiple regression analysis based on the TSA-model served for the identification of the physiological determinants most relevant for professional firefighting. Three main factors with great influence on firefighting performance were identified (70.1% of total explained variance): VO2peak, the time firefighter exercised below their individual ventilatory threshold and mean breathing frequency. Based on the identified main factors influencing firefighting performance we recommend a periodic preventive health screening for incumbents to monitor peak VO2 and individual ventilatory threshold.
A minimum cardiorespiratory fitness standard was derived for firefighters following a metabolic demands analysis. Design and minimal acceptable performance of generic firefighting task simulations (i.e. hose running, casualty evacuation, stair climb, equipment carry, wild-land fire) were endorsed by a panel of operationally experienced experts. Sixty-two UK firefighters completed these tasks wearing a standard protective firefighting ensemble while being monitored for peak steady-state metabolic demand and cardiovascular strain. Four tasks, endorsed as valid operational simulations by ≥90% of participants (excluding wild-land fire; 84%), were deemed to be a sufficiently valid and reliable basis for a fitness standard. These tasks elicited an average peak steady-state metabolic cost of 38.1 ± 7.8 ml kg−1 min−1. It is estimated that healthy adults can sustain the total duration of these tasks (~16 min) at ≤90% maximum oxygen uptake and a cardiorespiratory fitness standard of ≥42.3 ml kg−1 min−1 would be required to sustain work.
Practitioner Summary: A cardiorespiratory fitness standard for firefighters of ≥42.3 ml kg−1 min−1 was derived from monitoring minimum acceptable performance of essential tasks. This study supports the implementation of a routine assessment of this fitness standard for all UK operational firefighters, to ensure safe physical preparedness for occupational performance.
Firefighting is associated with high-level physical demands and requires appropriate physical fitness. Considering that obesity has been correlated with decreased cardiorespiratory fitness (CRF) and that the prevalence of obesity may also be elevated within firefighters (FF), we analyzed the association between CRF and body composition (BC) in Brazilian military firefighters. We assessed 4237 male FF (18-49 years of age) who performed a physical fitness test that included BC and CRF. Body Composition was assessed by body mass index (BMI), body adiposity index (BAI), body fat percentage (BF%) and waist circumference (WC). CRF was assessed by the 12-min Cooper test. Comparisons of VO2max between the BC categories were analyzed using the Mann-Whitney test, and the analysis was adjusted for age using the General Linear Model. The Spearman test was used for correlation analysis and the odds ratio (OR) was calculated to assess the odds of the unfit group (<=12 METs) for poor BC. Statistically significant differences were considered when p<0.05. Considering the BMI categories, eight volunteers (0.2%) were underweight, 1306 (30.8%) were normal weight, 2301 (54.3%) were overweight and 622 (14.7%) were obese. The VO2max was negatively correlated with age (rs=-0.21), BMI (rs =-0.45), WC (rs =-0.50) and BAI (rs =-0.35) (p<0.001). Cardiorespiratory fitness was lower in the obese compared with the non-obese for all age categories (-3.8 mL[middle dot]kg-1[middle dot]min-1;p<0.001) and for all BC indices (-4.5 mL[middle dot]kg-1[middle dot]min-1;p<0.001). The OR of the unfit group having poor BC in all indices varied from 2.9 to 8.1 (p<0.001). Despite the metabolically healthy obesity phenomenon, we found a strong association between CRF and BC irrespective of age and the BC method (BMI, BAI, WC or BF%). These findings may aid in improving FF training programs with a focus on health and performance. Copyright (C) 2015 by the National Strength & Conditioning Association.
Physical capacity has previously been deemed important for firefighters physical work capacity, and aerobic fitness, muscular strength, and muscular endurance are the most frequently investigated parameters of importance. Traditionally, bivariate and multivariate linear regression statistics have been used to study relationships between physical capacities and work capacities among firefighters. An alternative way to handle datasets consisting of numerous correlated variables is to use multivariate projection analyses, such as Orthogonal Projection to Latent Structures. The first aim of the present study was to evaluate the prediction and predictive power of field and laboratory tests, respectively, on firefighters' physical work capacity on selected work tasks. Also, to study if valid predictions could be achieved without anthropometric data. The second aim was to externally validate selected models. The third aim was to validate selected models on firefighters' and on civilians'. A total of 38 (26 men and 12 women) + 90 (38 men and 52 women) subjects were included in the models and the external validation, respectively. The best prediction (R2) and predictive power (Q2) of Stairs, Pulling, Demolition, Terrain, and Rescue work capacities included field tests (R2 = 0.73 to 0.84, Q2 = 0.68 to 0.82). The best external validation was for Stairs work capacity (R2 = 0.80) and worst for Demolition work capacity (R2 = 0.40). In conclusion, field and laboratory tests could equally well predict physical work capacities for firefighting work tasks, and models excluding anthropometric data were valid. The predictive power was satisfactory for all included work tasks except Demolition.
Sudden cardiac death (SCD) is the leading cause of death in firefighters. Although on-duty SCD usually occurs in older victims almost exclusively because of coronary heart disease, no studies have examined causation across the career span. In the present retrospective case-control study, cases of SCD in young (aged ≤45 years) firefighters from the National Institute for Occupational Safety and Health fatality investigations (n = 87) were compared with 2 age- and gender-matched control groups: occupationally active firefighters (n = 915) and noncardiac traumatic firefighter fatalities (n = 56). Of the SCD cases, 63% were obese and 67% had a coronary heart disease-related cause of death. The SCD victims had much heavier hearts (522 ± 102 g) than noncardiac fatality controls (400 ± 91 g, p <0.001). Cardiomegaly (heart weight >450 g) was found in 66% of the SCD victims and conveyed a fivefold increase (95% confidence interval [CI] 1.93 to 12.4) in SCD risk. Furthermore, hypertension, including cases with left ventricular hypertrophy, increased SCD risk by 12-fold (95% CI 6.23 to 22.3) after multivariate adjustment. A history of cardiovascular disease and smoking were also independently associated with elevated SCD risk (odds ratio 6.89, 95% CI 2.87 to 16.5; and odds ratio 3.53, 95% CI 1.87 to 6.65, respectively). In conclusion, SCD in young firefighters is primarily related to preventable lifestyle factors. Obesity entry standards, smoking bans, and improved screening and/or wellness program are potential strategies to reduce SCD in younger firefighters.
Abstract Accurate measurement,of blood pressure is essential to classify, readings taken with , This Article
There is currently no universally recommended and accepted method of data processing within the science of indirect calorimetry for either mixing chamber or breath-by-breath systems of expired gas analysis. Exercise physiologists were first surveyed to determine methods used to process oxygen consumption ((.)VO2) data, and current attitudes to data processing within the science of indirect calorimetry. Breath-by-breath datasets obtained from indirect calorimetry during incremental exercise were then used to demonstrate the consequences of commonly used time, breath and digital filter post-acquisition data processing strategies. Assessment of the variability in breath-by-breath data was determined using multiple regression based on the independent variables ventilation (VE), and the expired gas fractions for oxygen and carbon dioxide, FEO2 and FECO2, respectively. Based on the results of explanation of variance of the breath-by-breath (.)VO2 data, methods of processing to remove variability were proposed for time-averaged, breath-averaged and digital filter applications. Among exercise physiologists, the strategy used to remove the variability in (.)VO2 measurements varied widely, and consisted of time averages (30 sec [38%], 60 sec [18%], 20 sec [11%], 15 sec [8%]), a moving average of five to 11 breaths (10%), and the middle five of seven breaths (7%). Most respondents indicated that they used multiple criteria to establish maximum ((.)VO2 ((.)VO2max) including: the attainment of age-predicted maximum heart rate (HR(max)) [53%], respiratory exchange ratio (RER) >1.10 (49%) or RER >1.15 (27%) and a rating of perceived exertion (RPE) of >17, 18 or 19 (20%). The reasons stated for these strategies included their own beliefs (32%), what they were taught (26%), what they read in research articles (22%), tradition (13%) and the influence of their colleagues (7%). The combination of VE, FEO2 and FECO2 removed 96-98% of (.)VO2 breath-by-breath variability in incremental and steady-state exercise (.)VO2 data sets, respectively. Correction of residual error in (.)VO2 datasets to 10% of the raw variability results from application of a 30-second time average, 15-breath running average, or a 0.04 Hz low cut-off digital filter. Thus, we recommend that once these data processing strategies are used, the peak or maximal value becomes the highest processed datapoint. Exercise physiologists need to agree on, and continually refine through empirical research, a consistent process for analysing data from indirect calorimetry.
The aim of this research was to determine physiologic responses to typical activities of military Italian firefighters. Heart rate (HR), metabolic equivalent units (MET), skin temperature ( T.Sk.), and galvanic skin response (GSR) were measured in 13 firefighters (age = 36.3 +/- 6.9 yr; period of military fire service = 16.8 +/- 7 yr) during the acclimation phase (5 min standing, still dressed in their protective clothing), the work phase (simulated firefighting situations), and the following 24 hours. Multivariate linear step-wise regression showed that body mass index was highly correlated with mean and minimal HR values during the acclimation phase (beta 0.59, p < 0.001; beta 1.90, p = 0.003) and with mean and maximum HR values during the work phase (beta 1.08, p = 0.05; beta 1.17, p = 0.04), increasing cardiovascular stress. Firefighting tasks were associated with high energy expenditure. The minimum and mean MET values, during the acclimation phase, were significantly correlated with age (beta 0.49, p = 0.008 and beta 0.46, p < 0.01). During the work phase, maximal MET values were also strongly correlated with weight (beta 0.51, p = 0.03). No correlations between predictor and dependent variables were found for GSR; however, the high GSR levels recorded during the work phase returned to normal values only 12 hours after completion of the work phase, indicating that high levels of psychological stress remain, even after physical recovery. The data obtained in this study demonstrate that the physical fitness and anthropometric characteristics of firefighters influence the performance of firefighting tasks. These results may be useful to set up specific training that meets the real needs of firefighters in terms of physical fitness.
The occupation of firefighting is one that has repeatedly attracted the research interests of ergonomics. Among the activities encountered are attention to live fires, performing search and rescue of victims, and dealing with emergencies. The scientific literature is reviewed to highlight the investigative models used to contribute to the knowledge base about the ergonomics of firefighting, in particular to establish the multi-variate demands of the job and the attributes and capabilities of operators to cope with these demands. The job requires individuals to be competent in aerobic and anaerobic power and capacity, muscle strength, and have an appropriate body composition. It is still difficult to set down thresholds for values in all the areas in concert. Physiological demands are reflected in metabolic, circulatory, and thermoregulatory responses and hydration status, whilst psychological strain can be partially reflected in heart rate and endocrine measures. Research models have comprised of studying live fires, but more commonly in simulations in training facilities or treadmills and other ergometers. Wearing protective clothing adds to the physiological burden, raising oxygen consumption and body temperature, and reducing the time to fatigue. More sophisticated models of cognitive function compatible with decision-making in a fire-fighting context need to be developed. Recovery methods following a fire-fighting event have focused on accelerating the restoration towards homeostasis. The effectiveness of different recovery strategies is considered, ranging from passive cooling and wearing of cooling jackets to immersions in cold water and combinations of methods. Rehydration is also relevant in securing the safety of firefighters prior to returning for the next event in their work shift.
The purpose of this project was to identify the relationships between various fitness parameters such as upper body muscular endurance, upper and lower body strength, flexibility, body composition and performance on an ability test (AT) that included simulated firefighting tasks. A second intent was to create a regression model that would predict firefighter performance on the test. Thirty-eight experienced firefighters performed the AT and underwent assessments for the fitness parameters. Multiple regression analyses indicated that variation in the fitness parameters explained a significant, F(6, 36) = 6.31, p < .001, proportion (55%) of the variation observed in the AT. The results demonstrated that upper muscular strength and endurance as well as low body composition were significantly related (p < .01) to better performances on the simulated firefighting tasks. Variables such as low back and hamstring flexibility, upper and lower body strength, and body composition may contribute significantly to the model's predictive power.
Authoratative compilation of guidelines for exercise testing and prescription.
Sudden cardiac death accounted for 42% of all firefighter duty-related fatalities over the last decade. This retrospective study analyzed available medical examiner records for duty-related firefighter fatalities among male firefighters 18 to 65 years of age that occurred between 1999 and 2014 and reported the pathoanatomic substrate for cardiac-related fatalities. Odds of duty-related cardiac death during specific duties compared with fire station duties were calculated by pathoanatomic substrate. There were 285 cardiac fatalities. Of fatalities, 80% had evidence at autopsy of coronary heart disease (CHD) and increased heart size (cardiomegaly and/or left ventricular hypertrophy). CHD alone, cardiomegaly or left ventricular hypertrophy, and causes other than CHD or increased heart size were identified in 7.7%, 6.0%, and 6.7% of fatalities, respectively. The largest proportion of deaths occurred during fire suppression (33%), although only 1% of annual occupational time was estimated to be spent performing this duty. For deaths attributed to CHD and increased heart size, fire suppression, alarm response, and physical training were associated with approximately a 112-fold, eightfold, and sevenfold increased risk of cardiac death, respectively, compared with station duties. In conclusion, the majority of firefighters who suffered a duty-related cardiac death had CHD and increased heart size, which was associated with a markedly increased risk of death during fire suppression compared with station duties. Targeted occupational medical screening for CHD and increased heart size may reduce duty-related cardiac deaths among firefighters.
Given the importance of body composition in maintaining optimal physical and functional capacities, the use of appropriate, field-based assessment tools should be a priority to assist in maintaining the occupational safety of firefighters and the community. For ease, body mass index (BMI) has often been used to assess these changes. However, it is limited in its accuracy. The purposes of this study were twofold; 1) to compare the validity of different measures of body composition against dual energy X-ray absorptiometry (DXA) in urban firefighters and 2) to assess these measures in their ability to provide meaningful interpretation of criteria-driven categories of adiposity. Sixty-four male Firefighters (age 44.0±9.5 years) underwent full anthropometric profiling (predictor equations used to determine body fat % (BF%)), bio-impedance analysis (BIA) and DXA assessments. Participants' BMI was calculated and BF % and lean mass were determined along with criteria-driven categorisations of adiposity. Anthropometric (skinfolds) predictor equations (e.g. mean bias -4.4 % for BF%) were typically closer to DXA measures, compared to BIA (9.4% for BF%). However, when determining categories of criteria-driven adiposity, BIA (42.9% overweight or obese) provided closer estimates to the DXA determined-distribution (44.6%) than anthropometric based measures (up to 40%). BMI appears an inappropriate measure for accurately determining categories of adiposity with 64.1% classified as overweight or obese. Given the logistical constraints of anthropometric profiling, and the closeness of BIA to DXA in adiposity categories, BIA may be a suitable alternative to DXA for assessing body composition in professional urban firefighters.
Because of its noninvasive approach, anthropometry is one of the oldest and most popular methods of estimating body composition. However, this practical approach is often misused and misinterpreted by both clinicians and researchers. This article reviews the major methods for estimating body composition in various populations, with emphasis on anthropometry. Steps that will help clinicians select an appropriate anthropometric equation and reduce errors include using the same measurement procedures described in the original study and making sure the equation is based on a similar sample of 50 to 150 subjects in terms of age, sex, and activity levels.
Background:
Cardiovascular disease (CVD) is documented as the leading cause of mortality in on-duty firefighters.
Aims:
To examine the prevalence of metabolic syndrome (MetS) components, cardiorespiratory fitness levels and the association between them in firefighters in Colorado, USA.
Methods:
This study included male and female Colorado firefighters. MetS was identified where three or more metabolic abnormalities were present, using Cholesterol Education Program/Adult Treatment Panel III guidelines. Cardiorespiratory fitness (indicated by VO2 max) was evaluated with the Bruce protocol. Poisson regression was conducted to examine the association between MetS components and VO2 max.
Results:
Among the 947 male and 76 female study subjects, MetS was present in 9% of all firefighters, in 5% of females and 10% of males. The mean age was 37 ± 10 years. MetS prevalence increased with age (from 3% at age <30 to 17% at 50 and older, data not shown). In addition, 35% had one and 19% had two abnormal MetS components and 49% of participants did not meet the minimum recommended VO2 max of 42.0 ml/kg/min. VO2 max was negatively associated with abnormal MetS components (incident rate ratios = 0.95, 95% confidence interval 0.94-0.96, P < 0.001).
Conclusions:
About one in 10 of these Colorado firefighters had MetS and nearly half had insufficient cardiorespiratory fitness. Comprehensive CVD risk management and cardiorespiratory fitness improvement are essential for firefighter health and safety.
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.
The importance of cardiorespiratory fitness (CRF) is well established. This report provides newly developed standards for CRF reference values derived from cardiopulmonary exercise testing (CPX) using cycle ergometry in the United States. Ten laboratories in the United States experienced in CPX administration with established quality control procedures contributed to the “Fitness Registry and the Importance of Exercise: A National Database” (FRIEND) Registry from April 2014 through May 2016. Data from 4494 maximal (respiratory exchange ratio, ≥1.1) cycle ergometer tests from men and women (20-79 years) from 27 states, without cardiovascular disease, were used to develop these references values. Percentiles of maximum oxygen consumption (VO2max) for men and women were determined for each decade from age 20 years through age 79 years. Comparisons of VO2max were made to reference data established with CPX data from treadmill data in the FRIEND Registry and previously published reports. As expected, there were significant differences between sex and age groups for VO2max (P<.01). For cycle tests within the FRIEND Registry, the 50th percentile VO2max of men and women aged 20 to 29 years declined from 41.9 and 31.0 mLO2/kg/min to 19.5 and 14.8 mLO2/kg/min for ages 70 to 79 years, respectively. The rate of decline in this cohort was approximately 10% per decade. The FRIEND Registry reference data will be useful in providing more accurate interpretations for the US population of CPX-measured VO2max from exercise tests using cycle ergometry compared with previous approaches based on estimations of standard differences from treadmill testing reference values.
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.
Objective:
To develop standards for cardiorespiratory fitness by establishing reference values derived from cardiopulmonary exercise testing (CPX) in the United States.
Patients and methods:
Eight laboratories in the US experienced in CPX administration with established quality control procedures contributed data from January 1, 2014, through February 1, 2015, from 7783 maximal (respiratory exchange ratio, ≥1.0) treadmill tests from men and women (aged 20-79 years) without cardiovascular disease (CVD) to the Fitness Registry and the Importance of Exercise: A National Data Base (FRIEND). Percentiles of maximal oxygen consumption (V˙o2max) for men and women were determined for each decade from 20 years of age through 79 years of age. Comparisons of V˙o2max were made to reference data established with CPX data from Norway and to US reference data established without CPX measurements.
Results:
There were significant differences between sex and age groups for V˙o2max. In FRIEND, the 50th percentile V˙o2max of men and women aged 20 to 29 years decreased from 48.0 and 37.6 mLO2·kg(-1)·min(-1) to 24.4 and 18.3 mLO2·kg(-1)·min(-1) for ages 70 to 79 years, respectively. The rate of decline in this cohort during a 5-decade period was approximately 10% per decade.
Conclusion:
These are the first cardiorespiratory fitness reference data using measures obtained from CPX in the United States. FRIEND can be used to provide a more accurate interpretation of measured V˙o2max from maximal exercise tests for the US population compared with previous standards on the basis of workload-derived estimations.
Objective: Australian rural fire crews safeguard the nation against the annual devastation of wildfire. We have previously reported that experienced firefighters identified seven physically demanding tasks for Australian rural fire crews suppressing wildfires. These firefighters rated the operational importance, typical duration, core fitness components, and likely frequency of the seven tasks. The intensity of these duties remains unknown. The aim of this study was to quantify the oxygen uptake (VO2), heart rate (HR) and movement speed responses during simulations of these physically demanding wildfire suppression tasks. Method: Twenty six rural firefighters (20 men, six women) performed up to seven tasks, during which time their HR and movement speed were recorded. The VO2 for each task was also calculated from the analysis of expired air collected in Douglas bags. Firefighters’ HR and movement speed were measured using HR monitors and portable global positioning system units, respectively. Results: The hose work tasks elicited a VO2 of 21-27 mL·kg-1·min-1 and peak HR of 77-87% age-predicted maximal HR (HRmax). Hand tool tasks were accompanied by VO2 of 28-34 mL·kg-1·min-1 and peak HR of 85-95%HRmax. Firefighters’ movement speed spanned 0.2 ± 0.1 to 1.8 ± 0.2 m·s-1 across the seven tasks. The cardiovascular responses in the hand tool tasks were, in most cases, higher (P<0.05) than during those elicited by the hose work tasks. Conclusions: The cardiovascular responses elicited during simulations of physically demanding wildfire suppression approximated those reported for similar tasks in urban and forestry fire fighting jurisdictions. The findings may prompt Australian rural fire agencies to consider cardiovascular disease risk screening and physical selection testing to ensure that healthy and fit firefighters are deployed to the fire ground.
In many athletic and occupational settings, the wearing of protective clothing in warm or hot environments creates conditions of uncompensable heat stress where the body is unable to maintain a thermal steady state. Therefore, special precautions must be taken to minimise the threat of thermal injury. Assuming that manipulations known to reduce thermoregulatory strain during compensable heat stress would be equally effective in an uncompensable heat stress environment is not valid. In this review, we discuss the impact of hydration status, aerobic fitness, endurance training, heat acclimation, gender, menstrual cycle, oral contraceptive use, body composition and circadian rhythm on heat tolerance while wearing protective clothing in hot environments. The most effective countermeasure is ensuring that the individual is adequately hydrated both before and throughout the exercise or work session. In contrast, neither short term aerobic training or heat acclimation significantly improve exercise-heat tolerance during uncompensable heat stress. While short term aerobic training is relatively ineffective, long term improvements in physical fitness appear to provide some degree of protection. Individuals with higher proportions of body fat have a lower heat tolerance because of a reduced capacity to store heat. Women not using oral contraceptives are at a thermoregulatory disadvantage during the luteal phase of the menstrual cycle. The use of oral contraceptives eliminates any differences in heat tolerance throughout the menstrual cycle but tolerance is reduced during the quasi-follicular phase compared with non-users. Diurnal variations in resting core temperature do not appear to influence tolerance to uncompensable heat stress.
Sudden cardiac deaths experienced by firefighters in the line of duty account for the largest proportion of deaths annually. Several fire service standards for fitness and wellness have been recommended but currently only 30% of U.S. fire departments are implementing programs for this purpose. The Department of Homeland Security Science and Technology Directorate has initiated the Physiological Health Assessment System for Emergency Responders (PHASER) program aiming to reduce these line-of-duty deaths through an integration of medical science and sensor technologies. Confirming previous reports, PHASER comprehensive risk assessment has identified lack of physical fitness with propensity for overexertion as a major modifiable risk factor. We sought to determine if current levels of fitness and cardiovascular disease (CVD) risk factors in a contemporary cohort of firefighters were better than those reported over the past 30 years. Fifty-one firefighters from a Southern California department were characterized for physical fitness and CVD risk factors using standard measures. Overall, physical fitness and risk factors were not different from previous reports of firefighter fitness and most subjects did not achieve recommended fitness standards. Considering the lack of widespread implementation of wellness/fitness programs in the U.S. fire service together with our findings that low physical fitness and the presence of CVD risk factors persist, we issue a call to action among health and fitness professionals to assist the fire service in implementing programs for firefighters that improve fitness and reduce CVD risk factors. Fitness professionals should be empowered to work with fire departments lending their expertise to guide programs that achieve these objectives, which may then lead to reduced incidence of sudden cardiac death or stroke.
Unlabelled:
During live-fire firefighting operations and training evolutions, firefighters often consume multiple cylinders of air and continue to wear their personal protective equipment even after fire suppression activities have ceased. However, most studies have only reported core temperature changes during short-term firefighting activities and have shown a very modest increase in core temperature. Therefore, the purpose of this study is to evaluate core temperature and heart rate (HR) during repeated bouts of firefighting activity over ∼3 h. The results of this study show that core temperatures increase by an average of 1.9°C--to a larger magnitude than previously reported--and continue to increase during subsequent work cycles (38.4 vs. 38.7) even after long breaks of more than 30 min. The rate of core temperature increase during work continues to increase later in the training exercise (from 0.036 to 0.048°C/min), increasing the risk for exertional heat stress particularly if long-duration firefighting activity is required at these later times.
Practitioner summary:
To date, core temperature and HR changes during firefighting have been reported for short-term studies, which may significantly underestimate the physiological burden of typical firefighting activities. Firefighter core temperatures are shown to increase to a larger magnitude than previously observed and the rate of rise in core temperature increases during subsequent firefighting activities.
This study aimed to 1) analyze the energy requirement (VO2eq) and the contribution of the aerobic (VO2ex), anaerobic alactic (VO2al), and anaerobic lactic (VO2la-) energy sources of a simulated intervention; 2) ascertain differences in mean VO2 and heart rate (HR) during firefighting tasks; and 3) verify the relationship between time of job completion and the fitness level of firefighters. Twenty Italian firefighters (age = 32 ± 6 yr, VO2peak = 43.1 ± 4.9 mL·kg·min) performed 4 consecutive tasks (i.e., child rescue; 250-m run; find an exit; 250-m run) that required a VO2eq of 406.26 ± 73.91 mL·kg (VO2ex = 86 ± 5%; VO2al = 9 ± 3%; VO2la- = 5 ± 3%). After 30 minutes, the recovery HR (108 ± 15 beats·min) and VO2 (8.86±2.67mL·kg·min) were higher (p < 0.0001) than basal values (HR = 66 ± 8 beats·min; VO2 = 4.57 ± 1.07 mL·kg·min), indicating that passive recovery is insufficient in reducing the cardiovascular and thermoregulatory strain of the previous workload. Differences (p < 0.001) between tasks emerged for mean VO2 and HR, with a lack of significant correlation between the time of job completion and the firefighters' aerobic fitness. These findings indicate that unpredictable working conditions highly challenge expert firefighters who need adequate fitness levels to meet the requirements of their work. Practically, to enhance the fitness level of firefighters, specific interval training programs should include a wide variety of tasks requiring different intensities and decision-making strategies.
Objective:
Firefighting is a dangerous profession with high injury rates, particularly musculoskeletal (MS), but limited longitudinal data is available to examine predictors of MS injuries in this population.
Design and methods:
The relationship between personal individual, nonoccupational factors (e.g., demographic characteristics, body composition, fitness, and health behaviors) and incident injury and incident MS injury in a prospective cohort of 347 firefighters from the central United States was examined.
Results:
Baseline weight status was a significant predictor of incident MS injury, with obese (BMI ≥ 30 kg m(-2)) firefighters 5.2 times more likely (95% CI = 1.1-23.4) to experience a MS injury than their normal weight (BMI = 18.5-24.9 kg m(-2)) colleagues over the course of the study. Similarly, firefighters who were obese based on WC (>102.0 cm) were almost three times as likely (OR = 2.8, 95% CI = 1.2-6.4) to have a MS injury at follow-up.
Conclusions:
Findings highlight the importance of focusing on firefighters' body composition, nutrition and fitness as a means of decreasing risk for injury.
This study establishes and subsequently validates a minimum cutoff for the cardiovascular fitness of firefighters. Volunteers (n = 150) representing five discrete age classifications from 20 to 65 years were selected randomly for testing on their cardiovascular and pulmonary status. Discriminant function analysis was used to identify a group (n = 20) of firefighters to be monitored on heart rate (HR), oxygen consumption (vo,), and inspired ventilation (v,) during performance of a simulated fire-suppression protocol. Average VO, rnax of the subject group was 39.9 + 5.1 mlskg-lamin-1. They worked at 76 + 8% of VO, rnax with a V, of 46.7 + 3.4 lomin-1. The HR attained was 173 + 9 beatdmin. Based on these data a minimum VO, rnax of 33.5 ml. kg-1-min-1 was proposed as appropriate in order to maintain performance effectiveness. Concurrent validity of the proposed cutoff was examined in 32 additional firefighters. Individuals with VO, max values between 33.5-5 1.0 ml kg- I. min- had a significantly higher probability of successfully completing a fire-suppression protocol than firefighters with a VO, rnax between 26.0-33.49 ml.kgl.min -1.
Recruits from 9 consecutive fire academy classes were assessed on a battery of strength and endurance measures at Weeks 1, 7, and 14 of training. Regression analyses using Week 1 measures indicated that strength variables were the primary predictors of performance on physically demanding firefighting tasks assessed at the completion of training. Incremental validity was obtained with the addition of aerobic capacity, which produced more accurate performance distinctions among recruits with high strength levels. Results showed predictive validity and linearity throughout the upper range of strength and endurance levels, but evidence of an increased drop-off in performance for recruits with strength levels below the male 25th percentile. Structural equation modeling, a more powerful and comprehensive approach to validation than traditional regression, provided strong support for the construct validity of general strength and endurance as predictors of firefighter performance on physically demanding fire suppression and rescue tasks.
A consistent relationship has been demonstrated between obesity and absenteeism in the workplace. However, most studies have focused on primarily sedentary occupational groups. Firefighting is a physically demanding profession that involves significant potential for exposure to dangerous situations and strenuous work. No studies to date have evaluated the impact of obesity on risk for absenteeism among firefighters. We examined the cross-sectional association between BMI and obesity and injury-related absenteeism. BMI, body fat percentage (BF%), waist circumference (WC), injury, and injury-related absenteeism were assessed in 478 career male firefighters. One hundred and fifteen firefighters reported an injury in the previous year and the number of days absent from work due to their injury. BMI was an independent predictor of absenteeism due to injury even after adjustment for confounding variables. Firefighters meeting the definition of class II and III obesity had nearly five times (odds ratio (OR) = 4.89; 95% confidence interval (CI) = 3.63-6.58) the number missed work days due to injury when compared to their normal weight counterparts and their elevated risk was greater than firefighters with class I obesity (OR = 2.71; 95% CI = 2.01-3.65) or those who were overweight (OR = 2.55; 95% CI = 1.90-3.41). The attributable per capita costs of class II and III obesity-related absenteeism over the last year were 254.00 per firefighter for class I obesity, and $74.41 per firefighter for overweight. Our findings suggest that class II and III obesity were associated with substantial attributable costs to employers and our cost estimates probably underestimate the actual financial burden.
To examine the prevalence of overweight and obesity in firefighters.
Body mass index (BMI), waist circumference, and body fat percentage (BF%) were assessed in 478 career and 199 volunteer male firefighters from randomly selected departments.
High prevalence rates of overweight + obesity (BMI ≥ 25 kg/m) and obesity (BMI ≥ 30 kg/m) were found in career (79.5%; 33.5%) and volunteer firefighters (78.4%; 43.2%). False-positive obesity misclassification based on BMI, compared to waist circumference and BF%, was low (9.8% and 2.9%, respectively). False negatives were much higher: 32.9% and 13.0%. Obese firefighters demonstrated unfavorable cardiovascular disease (CVD) profiles.
The prevalence of overweight and obesity exceeded that of the US general population. Contrary to common wisdom, obesity was even more prevalent when assessed by BF% than by BMI, and misclassifying muscular firefighters as obese by using BMI occurred infrequently.
The purpose of this study was to identify the relationships between various fitness parameters and firefighting performance on an "Ability Test" (AT) that included a set of 6 simulated firefighting tasks. The relationships between each fitness parameter and each task of the AT were determined. Ninety firefighters participated in this study (age 33 ± 7 years). The AT completion time was associated with abdominal strength (r = -0.53, p < 0.01), relative power (r = -0.44, p < 0.01), upper-body muscular endurance (push-ups, r = -0.27, p < 0.05) (sit-ups, r = -0.41, p < 0.01), and upper-body strength (1 repetition maximum bench press, r = -0.41, p < 0.01). In addition, poor performance on the AT was associated with high resting heart rate (r = 0.36, p < 0.01), high body mass index (r = 0.34, p < 0.01), high body fat (BF)% (r = 0.57, p < 0.01), increasing age (r = 0.42, p < 0.01), and large waist size (r = 0.67, p < 0.01). Multiple regression analyses indicated that a significant (F[5, 53] = 14.02, p < 0.01) proportion (60%) of the variation observed in the AT was explained by the variation of the fitness parameters used in the model. This study demonstrated that fitness variables, such as abdominal strength, power (step test), push-ups, resting Hr, and BF%, contributed significantly to the predictive power of firefighters' AT performance. The findings of this study may be useful to fire department instructors and trainers in the design and implementation of training programs that are more specifically tailored to improving both individual firefighting skills and general fire suppression performance.
Collation of the original: 57 leave ;28 cm. Vita. Thesis (Ph. D.)--Ohio State University, 1968. Bibliography: leaves 55-57. Microfiche (negative) of typescript.
Firefighters having higher cardiovascular fitness completed a series of simulated firefighting tasks more quickly than those having lower fitness. These results support the need of a high level of cardiovascular fitness for firefighters to ensure not only their safety, but that of fellow firefighters and rescue victims.
To characterize the physical demands associated with on-the-job use of current firefighting equipment and the performance of essential firefighting operations, an initial task analysis of all firefighting operations was followed by an in-depth physical and physiological characterization of those tasks deemed to be physically demanding. The most commonly encountered applications of strength and endurance were lifting and carrying objects (up to 80 lbs), pulling objects (up to 135 lbs), and working with objects in front of the body (up to 125 lbs). The most demanding firefighting operations required a mean VO2 of 41.5 ml/kg.min-1 with peak lactate concentrations of 6 to 13.2 mM. Ninety percent of the demanding firefighting operations that were studied required a mean VO2 of 23 ml/kg.min-1. These aerobic energy requirements corresponded to 85 and 50% VO2max, respectively. Therefore a minimum VO2max standard for firefighter applicants of 45 ml/kg.min-1 is recommended.
Maximal oxygen intake (V̇o2max) was measured, using an open circuit technique, during the last 2 to 4 minutes of a multistage treadmill test of maximal exercise in 151 men and 144 women of 29 to 73 years of age. V̇o2max was higher in men than in women (P < 0.0001), lower in sedentary than in physically active persons (P < 0.001 in men, < 0.01 in women), and diminished with age in cross-sectional comparisons. It was highly correlated with duration of exercise by this standardized protocol. Accordingly, by regression equations average normal values for healthy persons could be predicted from sex, activity status, and age; values expected on testing could be estimated from the duration of exercise.Over 800 measurements of V̇o2max were also made during submaximal exercise to define the aerobic requirements under these conditions of testing. This revealed different coefficients for slope and intercept of regression equation for relationship of V̇o2submax to duration of submaximal exercise.Functional aerobic impairment (FAI) is the per cent difference between observed (or estimated) V̇o2max and that predicted from age, sex, and activity status by regression equations. Nomograms for rapid derivation of FAI from age in years and duration of maximal exercise were constructed for healthy men, women, and cardiac men to facilitate clinical usage of these methods.Functional aerobic impairment was 23 per cent in a group of symptomatic hypertensive men; it was 24 per cent in men with healed myocardial infarction, free from angina on maximal exertion, but 41 per cent in men with angina of effort, with or without evidence of prior infarction. In men with either angina or only healed myocardial infarction, impairment was reduced during treatment with nitroglycerin.
There is a great demand for perceptual effort ratings in order to better understand man at work. Such ratings are important complements to behavioral and physiological measurements of physical performance and work capacity. This is true for both theoretical analysis and application in medicine, human factors, and sports. Perceptual estimates, obtained by psychophysical ratio-scaling methods, are valid when describing general perceptual variation, but category methods are more useful in several applied situations when differences between individuals are described. A presentation is made of ratio-scaling methods, category methods, especially the Borg Scale for ratings of perceived exertion, and a new method that combines the category method with ratio properties. Some of the advantages and disadvantages of the different methods are discussed in both theoretical-psychophysical and psychophysiological frames of reference.
Left ventricular function was examined during incremental work rates to maximum using simultaneous determinations of stroke volume, left ventricular ejection time (LVET), and diastolic filling time (DT). Seven endurance trained and seven untrained young adult males were studied on a cycle ergometer at matched heart rates of 90, 120, 140, 160, 180, and 190 bpm (+/- 1 bpm). Stroke volume of the untrained subjects reached a plateau at 120 bpm, but stroke volume of the trained subjects continued to increase to their maximum heart rate with no plateau. Throughout incremental work rates, LVET was significantly longer and DT was significantly shorter in the trained subjects. At a heart rate of 190 bpm, the corresponding rates of ventricular emptying and ventricular filling of the trained versus the untrained subjects were 20% and 71% greater, respectively (P < 0.01). We conclude that during incremental work rates the stroke volume of endurance trained athletes increases progressively to maximum with no plateau. In addition, although trained athletes rely on enhancements in both ventricular filling and ventricular emptying to augment stroke volume, by far their major advantage over untrained subjects is in ventricular filling.
Historically, the achievement of maximal oxygen uptake (VO2max) has been based on objective criteria such as a leveling off of oxygen uptake with an increase in work rate, high levels of lactic acid in the blood in the minutes following the exercise test, elevated respiratory exchange ratio, and achievement of some percentage of an age-adjusted estimate of maximal heart rate. These criteria are reviewed relative to their history, the degree to which they have been achieved in published research, and how investigators and reviewers follow them in current practice. The majority of the criteria were based on discontinuous protocols, often carried out over several days. Questions are raised about the applicability of these criteria to modern continuous graded exercise test protocols, and our lack of consistency in the terminology we use relative to the measurement of maximal oxygen uptake.