Relationship between Body Mass Index and Health and Occupational Performance among Law Enforcement Officers, Firefighters, and Military Personnel: A Systematic Review

The prevalence of overweight and obesity among tactical populations is estimated at 70%-75%, which may negatively impact health and performance. The relationship between 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 officer, 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 12 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.

Cardiorespiratory Fitness of Firefighters: Initial Results of a Multi-Phased Study

OBJECTIVE

To address which body composition (BC) measures best correlate with cardiorespiratory fitness (CRF) in firefighters and develop a model for accurate CRF estimation compared with traditional methods.

METHODS

Career firefighters had body mass index (BMI) and waist circumference (WC) measured in addition to body fat percentage (FM%) by dual-energy x-ray absorptiometry (DXA). CRF as maximum oxygen uptake (VO2max) was estimated by rowing machine and measured by indirect calorimetry in a treadmill exercise test.

RESULTS

Fifty two firefighters participated (92.3% men). Univariate correlations with BMI were best with WC. Univariate correlations with VO2max were best with FM%. Obesity classifications by BC measures agreed weakly at best. Multivariate analysis of several variables yielded an improved VO2max estimate (R2 = 0.70).

CONCLUSIONS

Fire departments may benefit from more sophisticated measures of BC and CRF to evaluate firefighter fitness.

Relationships between anthropometric adiposity indexes and bone mineral density in a cross-sectional Chinese study

BACKGROUND CONTEXT

Previous studies have reported conflicting results for the relationships between anthropometric adiposity indexes and bone mineral density, based on dual-energy X-ray absorptiometry (DXA). However, few studies were published based on quantitative computed tomography (QCT), especially for Chinese population.

PURPOSE

To evaluate the associations of spine bone mineral density (BMD) with body mass index (BMI), waist circumstance (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR) and a body shape index (ABSI) using QCT.

STUDY DESIGN/SETTING

A Cross-sectional study.

PATIENT SAMPLE

Around 3,457 participants in multiple communities across 7 administrative regions of China.

OUTCOME MEASURES

Spine BMD was measured using QCT, and the classification of osteoporosis was defined as follows: 1) osteoporosis if BMD <80mg/cm³, 2) osteopenia if BMD 80-119 mg/cm³, and 3) normal bone mass if BMD≥120 mg/cm³.

METHODS

This study was conducted using convenient sampling between 2013 and 2017. Multivariable linear regression model and logistic regression models were used for the associations of continuous and categorical BMD, respectively.

RESULTS

Around 3,405 participants were included in the final analyses, including 1,272 males and 2,133 females, with spine BMD of 111.00±35.47 mg/cm³ and 99.38±40.60 mg/cm³, respectively. Spine BMD decreased significantly with the increase of ABSI in females (adjusted β, -5.74; 95% confidence interval [CI], -8.50 to -2.98), and this trend also was kept in females aged at less than 60 years (adjusted β, -14.54; 95% CI, -20.40 to -8.68), and females with age ≥60 years (adjusted β, -7.59; 95% CI, -10.91 to -4.28). However, this inverse association was observed only in males with age ≥ 60 years (adjusted β, -5.19; 95% CI, -10.08 to -0.29). Except ABSI, negative associations of Spine BMD with WC (adjusted β, -0.46; 95% CI, -0.77 to -0.15), WHR (adjusted β, -6.25; 95% CI, -10.63 to -1.86), WHtR (adjusted β, -6.80; 95% CI, -11.63 to -1.97) were shown in females aged at <60 years, and positive association with BMI in males with age ≥60 years (adjusted β, 0.92; 95% CI, 0.29-1.55).

CONCLUSIONS

ABSI had more remarkable association with spine BMD, compared with the other four indexes.

Body fatness in sedentary and active students with different body mass index

Study aim: Numerous data have indicated that body fat stores undergo complicated regulation by genetic and environmental factors, including physical activity. However, the majority of studies did not take into account this aspect of lifestyle in proposed body fat limits. In this context it seems that a more precise and reliable classification of body fat is provided by the American Council on Exercise (ACE), which distinguishes individuals not only with respect to sex but also activity level.

Material and methods: A total of 793 students (312 sedentary and 481 active) volunteered to participate in the study. Among sedentary participants 147 were male and 165 female. Among active subjects 206 were male and 275 were female. Active subjects were engaged in different modes of physical activity according to the study program. In all participants body mass index (BMI) was calculated. In participants with BMI 18.5–24.9 and BMI ≥ 25 body fat was determined using four skinfold measurements. Thereafter participants were classified according to the percentage of body fat using ranges for males and females provided by the American Council on Exercise (ACE) (essential fat, athletes, fitness, average and obese fatness).

Results: None of the sedentary and active males with BMI 18.5–24.9 had high (obese) fat. In contrast, in sedentary males with BMI ≥ 25 16.4% were obese vs. 1.8% of obese active ones. In sedentary females BMI from 18.5 to 24.9 did not exclude obesity, which was found in 16.9% of participants. In sedentary females with BMI ≥ 25 most of the subjects (97.1%) were obese. In contrast, in active females with BMI ≥ 25 a similar percentage of participants had average and obese fat (53.3% and 46.7, respectively).

Discussion: Our study clearly demonstrated that BMI as a simple measure of body composition provides false information concerning true adiposity in physically active male and female students. A similar BMI did not exclude marked differences in the percentage of body fat in sedentary and active students.

Worldwide prevalence of obesity among firefighters: a systematic review protocol

INTRODUCTION

Obesity may interfere with job performance and increase the risk of injury during firefighting activity. Obesity also has many deleterious effects on health indices and is associated with higher all-cause mortality. Studies report a high prevalence of obesity in the fire service. Also, firefighters' work schedule (12-hour to 24-hour shifts) and food availability during night shifts may be related to weight gain. Studies in American firefighters have shown annual weight gain between 0.5 and 1.5 kg. This study aims to report the obesity prevalence in the fire service to describe how it varies based on country and region, job status, type of firefighter and gender.

METHODS AND ANALYSIS

The main outcome evaluated will be obesity prevalence. We will systematically search the literature databases PubMed, Medline, Web of Science, Sportdiscus, Academic Search Premier, Cumulative Index of Nursing and Allied Health Literature (CINAHL), SciTech Premium Collection, Sports Medicine & Education Index, Research Library and Scopus. One reviewer will perform the search. Two independent reviewers will select studies, extract data from eligible studies and evaluate their methodological and reporting quality. Agreement between reviewers will be measured using Cohen's kappa. Other data of interest will include age, body mass index, body fat percentage, job status (career, volunteer or military), years of service and type of firefighter (eg, structural and wildland firefighter). We will produce a narrative summary of our findings. Tables will be generated to summarise data.

ETHICS AND DISSEMINATION

This systematic review does not require ethics clearance since published studies with non-identifiable data will be used. The results of the systematic review will be disseminated via publication in a peer-reviewed journal and through conference presentations.

PROSPERO REGISTRATION NUMBER

CRD42019129122.

Occupation and metabolic syndrome: is there correlation? A cross sectional study in different work activity occupations of German firefighters and office workers

BACKGROUND

The treatment and prevention of the metabolic syndrome (MetS) is currently one of the major challenges in medicine. The impact of working conditions on metabolic risk has not been adequately studied. Our objective was to compare the prevalence of MetS and metabolic risk in two extremely different occupational groups: firefighters and office workers.

METHODS

A total of 143 male subjects (97 firefighters and 46 office workers) from Germany participated in the study. Anthropometric characteristics, metabolic risk parameters as well as laboratory parameters were collected. MetS was diagnosed according to criteria of the International Diabetes Federation.

RESULTS

Sedentary occupation showed a significant tendency towards obesity. Abdominal waist circumference was significantly greater in office workers than in firefighters [5.08 CI (1.44-8.71), p = 0.007]. Concerning metabolic risk factors, abnormal HDL, triglycerides, BMI, blood pressure and waist circumference values were more frequently found in office workers than in firefighters. The MetS was detected in almost 33 % of office workers as compared with only 14 % in firefighters (p = 0.015). Regarding MetS in an international comparison, the prevalence of MetS in German office workers was high and in firefighters it was extremely low.

CONCLUSIONS

Sedentary occupation as an office worker is associated with a high risk of MetS. Both groups need to be made aware of the metabolic risks, and health promoting concepts such as corporate sports activities or education in healthy nutrition need to be implemented to counteract the development of the MetS and cardiovascular risk factors.

Does body mass index misclassify physically active young men

OBJECTIVE

The purpose of this analysis was to determine the accuracy of age and gender adjusted BMI as a measure of body fat (BF) in U.S. Army Soldiers.

METHODS

BMI was calculated through measured height and weight (kg/m(2)) and body composition was determined by dual energy X-ray absorptiometry (DEXA). Linear regression was used to determine a BF prediction equation and examine the correlation between %BF and BMI. The sensitivity and specificity of BMI compared to %BF as measured by DEXA was calculated.

RESULTS

Soldiers (n = 110) were on average 23 years old, with a BMI of 26.4, and approximately 18% BF. The correlation between BMI and %BF (R = 0.86) was strong (p < 0.01). A sensitivity of 77% and specificity of 100% were calculated when using Army age adjusted BMI thresholds. The overall accuracy in determining if a Soldier met Army BMI standards and were within the maximum allowable BF or exceeded BMI standards and were over the maximum allowable BF was 83%.

CONCLUSION

Using adjusted BMI thresholds in populations where physical fitness and training are requirements of the job provides better accuracy in identifying those who are overweight or obese due to high BF.